Dr. Laurie Starkey

Dr. Laurie Starkey

Alcohols, Part I

Slide Duration:

Table of Contents

Section 1: Introduction to Organic Molecules
Introduction and Drawing Structures

49m 51s

Intro
0:00
Organic Chemistry
0:07
Organic
0:08
Inorganic
0:26
Examples of Organic Compounds
1:16
Review Some Chemistry Basics
5:23
Electrons
5:42
Orbitals (s,p,d,f)
6:12
Review Some Chemistry Basics
7:35
Elements & Noble Gases
7:36
Atom & Valance Shell
8:47
Review Some Chemistry Basics
11:33
Electronegative Elements
11:34
Which Is More Electronegative, C or N?
13:45
Ionic & Covalent Bonds
14:07
Ionic Bonds
14:08
Covalent Bonds
16:17
Polar Covalent Bonds
19:35
Polar Covalent Bonds & Electronegativities
19:37
Polarity of Molecules
22:56
Linear molecule
23:07
Bent Molecule
23:53
No Polar Bonds
24:21
Ionic
24:52
Line Drawings
26:36
Line Drawing Overview
26:37
Line Drawing: Example 1
27:12
Line Drawing: Example 2
29:14
Line Drawing: Example 3
29:51
Line Drawing: Example 4
30:34
Line Drawing: Example 5
31:21
Line Drawing: Example 6
32:41
Diversity of Organic Compounds
33:57
Diversity of Organic Compounds
33:58
Diversity of Organic Compounds, cont.
39:16
Diversity of Organic Compounds, cont.
39:17
Examples of Polymers
45:26
Examples of Polymers
45:27
Lewis Structures & Resonance

44m 25s

Intro
0:00
Lewis Structures
0:08
How to Draw a Lewis Structure
0:09
Examples
2:20
Lewis Structures
6:25
Examples: Lewis Structure
6:27
Determining Formal Charges
8:48
Example: Determining Formal Charges for Carbon
10:11
Example: Determining Formal Charges for Oxygen
11:02
Lewis Structures
12:08
Typical, Stable Bonding Patterns: Hydrogen
12:11
Typical, Stable Bonding Patterns: Carbon
12:58
Typical, Stable Bonding Patterns: Nitrogen
13:25
Typical, Stable Bonding Patterns: Oxygen
13:54
Typical, Stable Bonding Patterns: Halogen
14:16
Lewis Structure Example
15:17
Drawing a Lewis Structure for Nitric Acid
15:18
Resonance
21:58
Definition of Resonance
22:00
Delocalization
22:07
Hybrid Structure
22:38
Rules for Estimating Stability of Resonance Structures
26:04
Rule Number 1: Complete Octets
26:10
Rule Number 2: Separation of Charge
28:13
Rule Number 3: Negative and Positive Charges
30:02
Rule Number 4: Equivalent
31:06
Looking for Resonance
32:09
Lone Pair Next to a p Bond
32:10
Vacancy Next to a p Bond
33:53
p Bond Between Two Different Elements
35:00
Other Type of Resonance: Benzene
36:06
Resonance Example
37:29
Draw and Rank Resonance Forms
37:30
Acid-Base Reactions

1h 7m 46s

Intro
0:00
Acid-Base Reactions
0:07
Overview
0:08
Lewis Acid and Lewis Base
0:30
Example 1: Lewis Acid and Lewis Base
1:53
Example 2: Lewis Acid and Lewis Base
3:04
Acid-base Reactions
4:54
Bonsted-Lowry Acid and Bonsted-Lowry Base
4:56
Proton Transfer Reaction
5:36
Acid-Base Equilibrium
8:14
Two Acids in Competition = Equilibrium
8:15
Example: Which is the Stronger Acid?
8:40
Periodic Trends for Acidity
12:40
Across Row
12:41
Periodic Trends for Acidity
19:48
Energy Diagram
19:50
Periodic Trends for Acidity
21:28
Down a Family
21:29
Inductive Effects on Acidity
25:52
Example: Which is the Stronger Acid?
25:54
Other Electron-Withdrawing Group (EWG)
30:37
Inductive Effects on Acidity
32:55
Inductive Effects Decrease with Distance
32:56
Resonance Effects on Acidity
36:35
Examples of Resonance Effects on Acidity
36:36
Resonance Effects on Acidity
41:15
Small and Large Amount of Resonance
41:17
Acid-Base Example
43:10
Which is Most Acidic? Which is the Least Acidic?
43:12
Acid-Base Example
49:26
Which is the Stronger Base?
49:27
Acid-Base Example
53:58
Which is the Strongest Base?
53:59
Common Acids/Bases
1:00:45
Common Acids/Bases
1:00:46
Example: Determine the Direction of Equilibrium
1:04:51
Structures and Properties of Organic Molecules

1h 23m 35s

Intro
0:00
Orbitals and Bonding
0:20
Atomic Orbitals (AO)
0:21
Molecular Orbitals (MO)
1:46
Definition of Molecular Orbitals
1:47
Example 1: Formation of Sigma Bond and Molecular Orbitals
2:20
Molecular Orbitals (MO)
5:25
Example 2: Formation of Pi Bond
5:26
Overlapping E Levels of MO's
7:28
Energy Diagram
7:29
Electronic Transitions
9:18
Electronic Transitions
9:23
Hybrid Orbitals
12:04
Carbon AO
12:06
Hybridization
13:51
Hybrid Orbitals
15:02
Examples of Hybrid Orbitals
15:05
Example: Assign Hybridization
20:31
3-D Sketches
24:05
sp3
24:24
sp2
25:28
sp
27:41
3-D Sketches of Molecules
29:07
3-D Sketches of Molecules 1
29:08
3-D Sketches of Molecules 2
32:29
3-D Sketches of Molecules 3
35:36
3D Sketch
37:20
How to Draw 3D Sketch
37:22
Example 1: Drawing 3D Sketch
37:50
Example 2: Drawing 3D Sketch
43:04
Hybridization and Resonance
46:06
Example: Hybridization and Resonance
46:08
Physical Properties
49:55
Water Solubility, Boiling Points, and Intermolecular Forces
49:56
Types of 'Nonbonding' Interactions
51:47
Dipole-Dipole
52:37
Definition of Dipole-Dipole
52:39
Example: Dipole-Dipole Bonding
53:27
Hydrogen Bonding
57:14
Definition of Hydrogen Bonding
57:15
Example: Hydrogen Bonding
58:05
Van Der Waals/ London Forces
1:03:11
Van Der Waals/ London Forces
1:03:12
Example: Van Der Waals/ London Forces
1:04:59
Water Solubility
1:08:32
Water Solubility
1:08:34
Example: Water Solubility
1:09:05
Example: Acetone
1:11:29
Isomerism
1:13:51
Definition of Isomers
1:13:53
Constitutional Isomers and Example
1:14:17
Stereoisomers and Example
1:15:34
Introduction to Functional Groups
1:17:06
Functional Groups: Example, Abbreviation, and Name
1:17:07
Introduction to Functional Groups
1:20:48
Functional Groups: Example, Abbreviation, and Name
1:20:49
Alkane Structures

1h 13m 38s

Intro
0:00
Nomenclature of Alkanes
0:12
Nomenclature of Alkanes and IUPAC Rules
0:13
Examples: Nomenclature of Alkanes
4:38
Molecular Formula and Degrees of Unsaturation (DU)
17:24
Alkane Formula
17:25
Example: Heptane
17:58
Why '2n+2' Hydrogens?
18:35
Adding a Ring
19:20
Adding a p Bond
19:42
Example 1: Determine Degrees of Unsaturation (DU)
20:17
Example 2: Determine Degrees of Unsaturation (DU)
21:35
Example 3: Determine DU of Benzene
23:30
Molecular Formula and Degrees of Unsaturation (DU)
24:41
Example 4: Draw Isomers
24:42
Physical properties of Alkanes
29:17
Physical properties of Alkanes
29:18
Conformations of Alkanes
33:40
Conformational Isomers
33:42
Conformations of Ethane: Eclipsed and Staggered
34:40
Newman Projection of Ethane
36:15
Conformations of Ethane
40:38
Energy and Degrees Rotated Diagram
40:41
Conformations of Butane
42:28
Butane
42:29
Newman Projection of Butane
43:35
Conformations of Butane
44:25
Energy and Degrees Rotated Diagram
44:30
Cycloalkanes
51:26
Cyclopropane and Cyclobutane
51:27
Cyclopentane
53:56
Cycloalkanes
54:56
Cyclohexane: Chair, Boat, and Twist Boat Conformations
54:57
Drawing a Cyclohexane Chair
57:58
Drawing a Cyclohexane Chair
57:59
Newman Projection of Cyclohexane
1:02:14
Cyclohexane Chair Flips
1:04:06
Axial and Equatorial Groups
1:04:10
Example: Chair Flip on Methylcyclohexane
1:06:44
Cyclohexane Conformations Example
1:09:01
Chair Conformations of cis-1-t-butyl-4-methylcyclohexane
1:09:02
Stereochemistry

1h 40m 54s

Intro
0:00
Stereochemistry
0:10
Isomers
0:11
Stereoisomer Examples
1:30
Alkenes
1:31
Cycloalkanes
2:35
Stereoisomer Examples
4:00
Tetrahedral Carbon: Superimposable (Identical)
4:01
Tetrahedral Carbon: Non-Superimposable (Stereoisomers)
5:18
Chirality
7:18
Stereoisomers
7:19
Chiral
8:05
Achiral
8:29
Example: Achiral and Chiral
8:45
Chirality
20:11
Superimposable, Non-Superimposable, Chiral, and Achiral
20:12
Nomenclature
23:00
Cahn-Ingold-Prelog Rules
23:01
Nomenclature
29:39
Example 1: Nomenclature
29:40
Example 2: Nomenclature
31:49
Example 3: Nomenclature
33:24
Example 4: Nomenclature
35:39
Drawing Stereoisomers
36:58
Drawing (S)-2-bromopentane
36:59
Drawing the Enantiomer of (S)-2-bromopentane: Method 1
38:47
Drawing the Enantiomer of (S)-2-bromopentane: Method 2
39:35
Fischer Projections
41:47
Definition of Fischer Projections
41:49
Drawing Fischer Projection
43:43
Use of Fisher Projection: Assigning Configuration
49:13
Molecules with Two Chiral Carbons
51:49
Example A
51:42
Drawing Enantiomer of Example A
53:26
Fischer Projection of A
54:25
Drawing Stereoisomers, cont.
59:40
Drawing Stereoisomers Examples
59:41
Diastereomers
1:01:48
Drawing Stereoisomers
1:06:37
Draw All Stereoisomers of 2,3-dichlorobutane
1:06:38
Molecules with Two Chiral Centers
1:10:22
Draw All Stereoisomers of 2,3-dichlorobutane, cont.
1:10:23
Optical Activity
1:14:10
Chiral Molecules
1:14:11
Angle of Rotation
1:14:51
Achiral Species
1:16:46
Physical Properties of Stereoisomers
1:17:11
Enantiomers
1:17:12
Diastereomers
1:18:01
Example
1:18:26
Physical Properties of Stereoisomers
1:23:05
When Do Enantiomers Behave Differently?
1:23:06
Racemic Mixtures
1:28:18
Racemic Mixtures
1:28:21
Resolution
1:29:52
Unequal Mixtures of Enantiomers
1:32:54
Enantiomeric Excess (ee)
1:32:55
Unequal Mixture of Enantiomers
1:34:43
Unequal Mixture of Enantiomers
1:34:44
Example: Finding ee
1:36:38
Example: Percent of Composition
1:39:46
Section 2: Understanding Organic Reactions
Nomenclature

1h 53m 47s

Intro
0:00
Cycloalkane Nomenclature
0:17
Cycloalkane Nomenclature and Examples
0:18
Alkene Nomenclature
6:28
Alkene Nomenclature and Examples
6:29
Alkene Nomenclature: Stereochemistry
15:07
Alkenes With Two Groups: Cis & Trans
15:08
Alkenes With Greater Than Two Groups: E & Z
18:26
Alkyne Nomenclature
24:46
Alkyne Nomenclature and Examples
24:47
Alkane Has a Higher Priority Than Alkyne
28:25
Alcohol Nomenclature
29:24
Alcohol Nomenclature and Examples
29:25
Alcohol FG Has Priority Over Alkene/yne
33:41
Ether Nomenclature
36:32
Ether Nomenclature and Examples
36:33
Amine Nomenclature
42:59
Amine Nomenclature and Examples
43:00
Amine Nomenclature
49:45
Primary, Secondary, Tertiary, Quaternary Salt
49:46
Aldehyde Nomenclature
51:37
Aldehyde Nomenclature and Examples
51:38
Ketone Nomenclature
58:43
Ketone Nomenclature and Examples
58:44
Aromatic Nomenclature
1:05:02
Aromatic Nomenclature and Examples
1:05:03
Aromatic Nomenclature, cont.
1:09:09
Ortho, Meta, and Para
1:09:10
Aromatic Nomenclature, cont.
1:13:27
Common Names for Simple Substituted Aromatic Compounds
1:13:28
Carboxylic Acid Nomenclature
1:16:35
Carboxylic Acid Nomenclature and Examples
1:16:36
Carboxylic Acid Derivatives
1:22:28
Carboxylic Acid Derivatives
1:22:42
General Structure
1:23:10
Acid Halide Nomenclature
1:24:48
Acid Halide Nomenclature and Examples
1:24:49
Anhydride Nomenclature
1:28:10
Anhydride Nomenclature and Examples
1:28:11
Ester Nomenclature
1:32:50
Ester Nomenclature
1:32:51
Carboxylate Salts
1:38:51
Amide Nomenclature
1:40:02
Amide Nomenclature and Examples
1:40:03
Nitrile Nomenclature
1:45:22
Nitrile Nomenclature and Examples
1:45:23
Chemical Reactions

51m 1s

Intro
0:00
Chemical Reactions
0:06
Reactants and Products
0:07
Thermodynamics
0:50
Equilibrium Constant
1:06
Equation
2:35
Organic Reaction
3:05
Energy vs. Progress of Rxn Diagrams
3:48
Exothermic Reaction
4:02
Endothermic Reaction
6:54
Estimating ΔH rxn
9:15
Bond Breaking
10:03
Bond Formation
10:25
Bond Strength
11:35
Homolytic Cleavage
11:59
Bond Dissociation Energy (BDE) Table
12:29
BDE for Multiple Bonds
14:32
Examples
17:35
Kinetics
20:35
Kinetics
20:36
Examples
21:49
Reaction Rate Variables
23:15
Reaction Rate Variables
23:16
Increasing Temperature, Increasing Rate
24:08
Increasing Concentration, Increasing Rate
25:39
Decreasing Energy of Activation, Increasing Rate
27:49
Two-Step Mechanisms
30:06
E vs. POR Diagram (2-step Mechanism)
30:07
Reactive Intermediates
33:03
Reactive Intermediates
33:04
Example: A Carbocation
35:20
Carbocation Stability
37:24
Relative Stability of Carbocation
37:25
Alkyl groups and Hyperconjugation
38:45
Carbocation Stability
41:57
Carbocation Stabilized by Resonance: Allylic
41:58
Carbocation Stabilized by Resonance: Benzylic
42:59
Overall Carbocation Stability
44:05
Free Radicals
45:05
Definition and Examples of Free Radicals
45:06
Radical Mechanisms
49:40
Example: Regular Arrow
49:41
Example: Fish-Hook Arrow
50:17
Free Radical Halogenation

26m 23s

Intro
0:00
Free Radical Halogenation
0:06
Free Radical Halogenation
0:07
Mechanism: Initiation
1:27
Mechanism: Propagation Steps
2:21
Free Radical Halogenation
5:33
Termination Steps
5:36
Example 1: Terminations Steps
6:00
Example 2: Terminations Steps
6:18
Example 3: Terminations Steps
7:43
Example 4: Terminations Steps
8:04
Regiochemistry of Free Radical Halogenation
9:32
Which Site/Region Reacts and Why?
9:34
Bromination and Rate of Reaction
14:03
Regiochemistry of Free Radical Halogenation
14:30
Chlorination
14:31
Why the Difference in Selectivity?
19:58
Allylic Halogenation
20:53
Examples of Allylic Halogenation
20:55
Substitution Reactions

1h 48m 5s

Intro
0:00
Substitution Reactions
0:06
Substitution Reactions Example
0:07
Nucleophile
0:39
Electrophile
1:20
Leaving Group
2:56
General Reaction
4:13
Substitution Reactions
4:43
General Reaction
4:46
Substitution Reaction Mechanisms: Simultaneous
5:08
Substitution Reaction Mechanisms: Stepwise
5:34
SN2 Substitution
6:21
Example of SN2 Mechanism
6:22
SN2 Kinetics
7:58
Rate of SN2
9:10
Sterics Affect Rate of SN2
9:12
Rate of SN2 (By Type of RX)
14:13
SN2: E vs. POR Diagram
17:26
E vs. POR Diagram
17:27
Transition State (TS)
18:24
SN2 Transition State, Kinetics
20:58
SN2 Transition State, Kinetics
20:59
Hybridization of TS Carbon
21:57
Example: Allylic LG
23:34
Stereochemistry of SN2
25:46
Backside Attack and Inversion of Stereochemistry
25:48
SN2 Summary
29:56
Summary of SN2
29:58
Predict Products (SN2)
31:42
Example 1: Predict Products
31:50
Example 2: Predict Products
33:38
Example 3: Predict Products
35:11
Example 4: Predict Products
36:11
Example 5: Predict Products
37:32
SN1 Substitution Mechanism
41:52
Is This Substitution? Could This Be an SN2 Mechanism?
41:54
SN1 Mechanism
43:50
Two Key Steps: 1. Loss of LG
43:53
Two Key Steps: 2. Addition of nu
45:11
SN1 Kinetics
47:17
Kinetics of SN1
47:18
Rate of SN1 (By RX type)
48:44
SN1 E vs. POR Diagram
49:49
E vs. POR Diagram
49:51
First Transition Stage (TS-1)
51:48
Second Transition Stage (TS-2)
52:56
Stereochemistry of SN1
53:44
Racemization of SN1 and Achiral Carbocation Intermediate
53:46
Example
54:29
SN1 Summary
58:25
Summary of SN1
58:26
SN1 or SN2 Mechanisms?
1:00:40
Example 1: SN1 or SN2 Mechanisms
1:00:42
Example 2: SN1 or SN2 Mechanisms
1:03:00
Example 3: SN1 or SN2 Mechanisms
1:04:06
Example 4: SN1 or SN2 Mechanisms
1:06:17
SN1 Mechanism
1:09:12
Three Steps of SN1 Mechanism
1:09:13
SN1 Carbocation Rearrangements
1:14:50
Carbocation Rearrangements Example
1:14:51
SN1 Carbocation Rearrangements
1:20:46
Alkyl Groups Can Also Shift
1:20:48
Leaving Groups
1:24:26
Leaving Groups
1:24:27
Forward or Reverse Reaction Favored?
1:26:00
Leaving Groups
1:29:59
Making poor LG Better: Method 1
1:30:00
Leaving Groups
1:34:18
Making poor LG Better: Tosylate (Method 2)
1:34:19
Synthesis Problem
1:38:15
Example: Provide the Necessary Reagents
1:38:16
Nucleophilicity
1:41:10
What Makes a Good Nucleophile?
1:41:11
Nucleophilicity
1:44:45
Periodic Trends: Across Row
1:44:47
Periodic Trends: Down a Family
1:46:46
Elimination Reactions

1h 11m 43s

Intro
0:00
Elimination Reactions: E2 Mechanism
0:06
E2 Mechanism
0:08
Example of E2 Mechanism
1:01
Stereochemistry of E2
4:48
Anti-Coplanar & Anti-Elimination
4:50
Example 1: Stereochemistry of E2
5:34
Example 2: Stereochemistry of E2
10:39
Regiochemistry of E2
13:04
Refiochemistry of E2 and Zaitsev's Rule
13:05
Alkene Stability
17:39
Alkene Stability
19:20
Alkene Stability Examples
19:22
Example 1: Draw Both E2 Products and Select Major
21:57
Example 2: Draw Both E2 Products and Select Major
25:02
SN2 Vs. E2 Mechanisms
29:06
SN2 Vs. E2 Mechanisms
29:07
When Do They Compete?
30:34
SN2 Vs. E2 Mechanisms
31:23
Compare Rates
31:24
SN2 Vs. E2 Mechanisms
36:34
t-BuBr: What If Vary Base?
36:35
Preference for E2 Over SN2 (By RX Type)
40:42
E1 Elimination Mechanism
41:51
E1 - Elimination Unimolecular
41:52
E1 Mechanism: Step 1
44:14
E1 Mechanism: Step 2
44:48
E1 Kinetics
46:58
Rate = k[RCI]
47:00
E1 Rate (By Type of Carbon Bearing LG)
48:31
E1 Stereochemistry
49:49
Example 1: E1 Stereochemistry
49:51
Example 2: E1 Stereochemistry
52:31
Carbocation Rearrangements
55:57
Carbocation Rearrangements
56:01
Product Mixtures
57:20
Predict the Product: SN2 vs. E2
59:58
Example 1: Predict the Product
1:00:00
Example 2: Predict the Product
1:02:10
Example 3: Predict the Product
1:04:07
Predict the Product: SN2 vs. E2
1:06:06
Example 4: Predict the Product
1:06:07
Example 5: Predict the Product
1:07:29
Example 6: Predict the Product
1:07:51
Example 7: Predict the Product
1:09:18
Section 3: Alkanes, Alkenes, & Alkynes
Alkenes

36m 39s

Intro
0:00
Alkenes
0:12
Definition and Structure of Alkenes
0:13
3D Sketch of Alkenes
1:53
Pi Bonds
3:48
Alkene Stability
4:57
Alkyl Groups Attached
4:58
Trans & Cis
6:20
Alkene Stability
8:42
Pi Bonds & Conjugation
8:43
Bridgehead Carbons & Bredt's Rule
10:22
Measuring Stability: Hydrogenation Reaction
11:40
Alkene Synthesis
12:01
Method 1: E2 on Alkyl Halides
12:02
Review: Stereochemistry
16:17
Review: Regiochemistry
16:50
Review: SN2 vs. E2
17:34
Alkene Synthesis
18:57
Method 2: Dehydration of Alcohols
18:58
Mechanism
20:08
Alkene Synthesis
23:26
Alcohol Dehydration
23:27
Example 1: Comparing Strong Acids
26:59
Example 2: Mechanism for Dehydration Reaction
29:00
Example 3: Transform
32:50
Reactions of Alkenes

2h 8m 44s

Intro
0:00
Reactions of Alkenes
0:05
Electrophilic Addition Reaction
0:06
Addition of HX
2:02
Example: Regioselectivity & 2 Steps Mechanism
2:03
Markovnikov Addition
5:30
Markovnikov Addition is Favored
5:31
Graph: E vs. POR
6:33
Example
8:29
Example: Predict and Consider the Stereochemistry
8:30
Hydration of Alkenes
12:31
Acid-catalyzed Addition of Water
12:32
Strong Acid
14:20
Hydration of Alkenes
15:20
Acid-catalyzed Addition of Water: Mechanism
15:21
Hydration vs. Dehydration
19:51
Hydration Mechanism is Exact Reverse of Dehydration
19:52
Example
21:28
Example: Hydration Reaction
21:29
Alternative 'Hydration' Methods
25:26
Oxymercuration-Demercuration
25:27
Oxymercuration Mechanism
28:55
Mechanism of Oxymercuration
28:56
Alternative 'Hydration' Methods
30:51
Hydroboration-Oxidation
30:52
Hydroboration Mechanism
33:22
1-step (concerted)
33:23
Regioselective
34:45
Stereoselective
35:30
Example
35:58
Example: Hydroboration-Oxidation
35:59
Example
40:42
Example: Predict the Major Product
40:43
Synthetic Utility of 'Alternate' Hydration Methods
44:36
Example: Synthetic Utility of 'Alternate' Hydration Methods
44:37
Flashcards
47:28
Tips On Using Flashcards
47:29
Bromination of Alkenes
49:51
Anti-Addition of Br₂
49:52
Bromination Mechanism
53:16
Mechanism of Bromination
53:17
Bromination Mechanism
55:42
Mechanism of Bromination
55:43
Bromination: Halohydrin Formation
58:54
Addition of other Nu: to Bromonium Ion
58:55
Mechanism
1:00:08
Halohydrin: Regiochemistry
1:03:55
Halohydrin: Regiochemistry
1:03:56
Bromonium Ion Intermediate
1:04:26
Example
1:09:28
Example: Predict Major Product
1:09:29
Example Cont.
1:10:59
Example: Predict Major Product Cont.
1:11:00
Catalytic Hydrogenation of Alkenes
1:13:19
Features of Catalytic Hydrogenation
1:13:20
Catalytic Hydrogenation of Alkenes
1:14:48
Metal Surface
1:14:49
Heterogeneous Catalysts
1:15:29
Homogeneous Catalysts
1:16:08
Catalytic Hydrogenation of Alkenes
1:17:44
Hydrogenation & Pi Bond Stability
1:17:45
Energy Diagram
1:19:22
Catalytic Hydrogenation of Dienes
1:20:40
Hydrogenation & Pi Bond Stability
1:20:41
Energy Diagram
1:23:31
Example
1:24:14
Example: Predict Product
1:24:15
Oxidation of Alkenes
1:27:21
Redox Review
1:27:22
Epoxide
1:30:26
Diol (Glycol)
1:30:54
Ketone/ Aldehyde
1:31:13
Epoxidation
1:32:08
Epoxidation
1:32:09
General Mechanism
1:36:32
Alternate Epoxide Synthesis
1:37:38
Alternate Epoxide Synthesis
1:37:39
Dihydroxylation
1:41:10
Dihydroxylation
1:41:12
General Mechanism (Concerted Via Cycle Intermediate)
1:42:38
Ozonolysis
1:44:22
Ozonolysis: Introduction
1:44:23
Ozonolysis: Is It Good or Bad?
1:45:05
Ozonolysis Reaction
1:48:54
Examples
1:51:10
Example 1: Ozonolysis
1:51:11
Example
1:53:25
Radical Addition to Alkenes
1:55:05
Recall: Free-Radical Halogenation
1:55:15
Radical Mechanism
1:55:45
Propagation Steps
1:58:01
Atom Abstraction
1:58:30
Addition to Alkene
1:59:11
Radical Addition to Alkenes
1:59:54
Markovnivok (Electrophilic Addition) & anti-Mark. (Radical Addition)
1:59:55
Mechanism
2:01:03
Alkene Polymerization
2:05:35
Example: Alkene Polymerization
2:05:36
Alkynes

1h 13m 19s

Intro
0:00
Structure of Alkynes
0:04
Structure of Alkynes
0:05
3D Sketch
2:30
Internal and Terminal
4:03
Reductions of Alkynes
4:36
Catalytic Hydrogenation
4:37
Lindlar Catalyst
5:25
Reductions of Alkynes
7:24
Dissolving Metal Reduction
7:25
Oxidation of Alkynes
9:24
Ozonolysis
9:25
Reactions of Alkynes
10:56
Addition Reactions: Bromination
10:57
Addition of HX
12:24
Addition of HX
12:25
Addition of HX
13:36
Addition of HX: Mechanism
13:37
Example
17:38
Example: Transform
17:39
Hydration of Alkynes
23:35
Hydration of Alkynes
23:36
Hydration of Alkynes
26:47
Hydration of Alkynes: Mechanism
26:49
'Hydration' via Hydroboration-Oxidation
32:57
'Hydration' via Hydroboration-Oxidation
32:58
Disiamylborane
33:28
Hydroboration-Oxidation Cont.
34:25
Alkyne Synthesis
36:17
Method 1: Alkyne Synthesis By Dehydrohalogenation
36:19
Alkyne Synthesis
39:06
Example: Transform
39:07
Alkyne Synthesis
41:21
Method 2 & Acidity of Alkynes
41:22
Conjugate Bases
43:06
Preparation of Acetylide Anions
49:55
Preparation of Acetylide Anions
49:57
Alkyne Synthesis
53:40
Synthesis Using Acetylide Anions
53:41
Example 1: Transform
57:04
Example 2: Transform
1:01:07
Example 3: Transform
1:06:22
Section 4: Alcohols
Alcohols, Part I

59m 52s

Intro
0:00
Alcohols
0:11
Attributes of Alcohols
0:12
Boiling Points
2:00
Water Solubility
5:00
Water Solubility (Like Dissolves Like)
5:01
Acidity of Alcohols
9:39
Comparison of Alcohols Acidity
9:41
Preparation of Alkoxides
13:03
Using Strong Base Like Sodium Hydride
13:04
Using Redox Reaction
15:36
Preparation of Alkoxides
17:41
Using K°
17:42
Phenols Are More Acidic Than Other Alcohols
19:51
Synthesis of Alcohols, ROH
21:43
Synthesis of Alcohols from Alkyl Halides, RX (SN2 or SN1)
21:44
Synthesis of Alcohols, ROH
25:08
Unlikely on 2° RX (E2 Favored)
25:09
Impossible on 3° RX (E2) and Phenyl/Vinyl RX (N/R)
25:47
Synthesis of Alcohols, ROH
26:26
SN1 with H₂O 'Solvolysis' or 'Hydrolysis'
26:27
Carbocation Can Rearrange
29:00
Synthesis of Alcohols, ROH
30:08
Synthesis of Alcohols From Alkenes: Hydration
30:09
Synthesis of Alcohols From Alkenes: Oxidation/Diol
32:20
Synthesis of Alcohols, ROH
33:14
Synthesis of Alcohols From Ketones and Aldehydes
33:15
Organometallic Reagents: Preparation
37:03
Grignard (RMgX)
37:04
Organolithium (Rli)
40:03
Organometallic Reagents: Reactions
41:45
Reactions of Organometallic Reagents
41:46
Organometallic Reagents: Reactions as Strong Nu:
46:40
Example 1: Reactions as Strong Nu:
46:41
Example 2: Reactions as Strong Nu:
48:57
Hydride Nu:
50:52
Hydride Nu:
50:53
Examples
53:34
Predict 1
53:35
Predict 2
54:45
Examples
56:43
Transform
56:44
Provide Starting Material
58:18
Alcohols, Part II

45m 35s

Intro
0:00
Oxidation Reactions
0:08
Oxidizing Agents: Jones, PCC, Swern
0:09
'Jones' Oxidation
0:43
Example 1: Predict Oxidation Reactions
2:29
Example 2: Predict Oxidation Reactions
3:00
Oxidation Reactions
4:11
Selective Oxidizing Agents (PCC and Swern)
4:12
PCC (Pyridiniym Chlorochromate)
5:10
Swern Oxidation
6:05
General [ox] Mechanism
8:32
General [ox] Mechanism
8:33
Oxidation of Alcohols
10:11
Example 1: Oxidation of Alcohols
10:12
Example 2: Oxidation of Alcohols
11:20
Example 3: Oxidation of Alcohols
11:46
Example
13:09
Predict: PCC Oxidation Reactions
13:10
Tosylation of Alcohols
15:22
Introduction to Tosylation of Alcohols
15:23
Example
21:08
Example: Tosylation of Alcohols
21:09
Reductions of Alcohols
23:39
Reductions of Alcohols via SN2 with Hydride
24:22
Reductions of Alcohols via Dehydration
27:12
Conversion of Alcohols to Alkyl Halides
30:12
Conversion of Alcohols to Alkyl Halides via Tosylate
30:13
Conversion of Alcohols to Alkyl Halides
31:17
Using HX
31:18
Mechanism
32:09
Conversion of Alcohols to Alkyl Halides
35:43
Reagents that Provide LG and Nu: in One 'Pot'
35:44
General Mechanisms
37:44
Example 1: General Mechanisms
37:45
Example 2: General Mechanisms
39:25
Example
41:04
Transformation of Alcohols
41:05
Section 5: Ethers, Thiols, Thioethers, & Ketones
Ethers

1h 34m 45s

Intro
0:00
Ethers
0:11
Overview of Ethers
0:12
Boiling Points
1:37
Ethers
4:34
Water Solubility (Grams per 100mL H₂O)
4:35
Synthesis of Ethers
7:53
Williamson Ether Synthesis
7:54
Example: Synthesis of Ethers
9:23
Synthesis of Ethers
10:27
Example: Synthesis of Ethers
10:28
Intramolecular SN2
13:04
Planning an Ether Synthesis
14:45
Example 1: Planning an Ether Synthesis
14:46
Planning an Ether Synthesis
16:16
Example 2: Planning an Ether Synthesis
16:17
Planning an Ether Synthesis
22:04
Example 3: Synthesize Dipropyl Ether
22:05
Planning an Ether Synthesis
26:01
Example 4: Transform
26:02
Synthesis of Epoxides
30:05
Synthesis of Epoxides Via Williamson Ether Synthesis
30:06
Synthesis of Epoxides Via Oxidation
32:42
Reaction of Ethers
33:35
Reaction of Ethers
33:36
Reactions of Ethers with HBr or HI
34:44
Reactions of Ethers with HBr or HI
34:45
Mechanism
35:25
Epoxide Ring-Opening Reaction
39:25
Epoxide Ring-Opening Reaction
39:26
Example: Epoxide Ring-Opening Reaction
42:42
Acid-Catalyzed Epoxide Ring Opening
44:16
Acid-Catalyzed Epoxide Ring Opening Mechanism
44:17
Acid-Catalyzed Epoxide Ring Opening
50:13
Acid-Catalyzed Epoxide Ring Opening Mechanism
50:14
Catalyst Needed for Ring Opening
53:34
Catalyst Needed for Ring Opening
53:35
Stereochemistry of Epoxide Ring Opening
55:56
Stereochemistry: SN2 Mechanism
55:57
Acid or Base Mechanism?
58:30
Example
1:01:03
Transformation
1:01:04
Regiochemistry of Epoxide Ring Openings
1:05:29
Regiochemistry of Epoxide Ring Openings in Base
1:05:30
Regiochemistry of Epoxide Ring Openings in Acid
1:07:34
Example
1:10:26
Example 1: Epoxide Ring Openings in Base
1:10:27
Example 2: Epoxide Ring Openings in Acid
1:12:50
Reactions of Epoxides with Grignard and Hydride
1:15:35
Reactions of Epoxides with Grignard and Hydride
1:15:36
Example
1:21:47
Example: Ethers
1:21:50
Example
1:27:01
Example: Synthesize
1:27:02
Thiols and Thioethers

16m 50s

Intro
0:00
Thiols and Thioethers
0:10
Physical Properties
0:11
Reactions Can Be Oxidized
2:16
Acidity of Thiols
3:11
Thiols Are More Acidic Than Alcohols
3:12
Synthesis of Thioethers
6:44
Synthesis of Thioethers
6:45
Example
8:43
Example: Synthesize the Following Target Molecule
8:44
Example
14:18
Example: Predict
14:19
Ketones

2h 18m 12s

Intro
0:00
Aldehydes & Ketones
0:11
The Carbonyl: Resonance & Inductive
0:12
Reactivity
0:50
The Carbonyl
2:35
The Carbonyl
2:36
Carbonyl FG's
4:10
Preparation/Synthesis of Aldehydes & Ketones
6:18
Oxidation of Alcohols
6:19
Ozonolysis of Alkenes
7:16
Hydration of Alkynes
8:01
Reaction with Hydride Nu:
9:00
Reaction with Hydride Nu:
9:01
Reaction with Carbon Nu:
11:29
Carbanions: Acetylide
11:30
Carbanions: Cyanide
14:23
Reaction with Carbon Nu:
15:32
Organometallic Reagents (RMgX, Rli)
15:33
Retrosynthesis of Alcohols
17:04
Retrosynthesis of Alcohols
17:05
Example
19:30
Example: Transform
19:31
Example
22:57
Example: Transform
22:58
Example
28:19
Example: Transform
28:20
Example
33:36
Example: Transform
33:37
Wittig Reaction
37:39
Wittig Reaction: A Resonance-Stabilized Carbanion (Nu:)
37:40
Wittig Reaction: Mechanism
39:51
Preparation of Wittig Reagent
41:58
Two Steps From RX
41:59
Example: Predict
45:02
Wittig Retrosynthesis
46:19
Wittig Retrosynthesis
46:20
Synthesis
48:09
Reaction with Oxygen Nu:
51:21
Addition of H₂O
51:22
Exception: Formaldehyde is 99% Hydrate in H₂O Solution
54:10
Exception: Hydrate is Favored if Partial Positive Near Carbonyl
55:26
Reaction with Oxygen Nu:
57:45
Addition of ROH
57:46
TsOH: Tosic Acid
58:28
Addition of ROH Cont.
59:09
Example
1:01:43
Predict
1:01:44
Mechanism
1:03:08
Mechanism for Acetal Formation
1:04:10
Mechanism for Acetal Formation
1:04:11
What is a CTI?
1:15:04
Tetrahedral Intermediate
1:15:05
Charged Tetrahedral Intermediate
1:15:45
CTI: Acid-cat
1:16:10
CTI: Base-cat
1:17:01
Acetals & Cyclic Acetals
1:17:49
Overall
1:17:50
Cyclic Acetals
1:18:46
Hydrolysis of Acetals: Regenerates Carbonyl
1:20:01
Hydrolysis of Acetals: Regenerates Carbonyl
1:20:02
Mechanism
1:22:08
Reaction with Nitrogen Nu:
1:30:11
Reaction with Nitrogen Nu:
1:30:12
Example
1:32:18
Mechanism of Imine Formation
1:33:24
Mechanism of Imine Formation
1:33:25
Oxidation of Aldehydes
1:38:12
Oxidation of Aldehydes 1
1:38:13
Oxidation of Aldehydes 2
1:39:52
Oxidation of Aldehydes 3
1:40:10
Reductions of Ketones and Aldehydes
1:40:54
Reductions of Ketones and Aldehydes
1:40:55
Hydride/ Workup
1:41:22
Raney Nickel
1:42:07
Reductions of Ketones and Aldehydes
1:43:24
Clemmensen Reduction & Wolff-Kishner Reduction
1:43:40
Acetals as Protective Groups
1:46:50
Acetals as Protective Groups
1:46:51
Example
1:50:39
Example: Consider the Following Synthesis
1:50:40
Protective Groups
1:54:47
Protective Groups
1:54:48
Example
1:59:02
Example: Transform
1:59:03
Example: Another Route
2:04:54
Example: Transform
2:08:49
Example
2:08:50
Transform
2:08:51
Example
2:11:05
Transform
2:11:06
Example
2:13:45
Transform
2:13:46
Example
2:15:43
Provide the Missing Starting Material
2:15:44
Section 6: Organic Transformation Practice
Transformation Practice Problems

38m 58s

Intro
0:00
Practice Problems
0:33
Practice Problem 1: Transform
0:34
Practice Problem 2: Transform
3:57
Practice Problems
7:49
Practice Problem 3: Transform
7:50
Practice Problems
15:32
Practice Problem 4: Transform
15:34
Practice Problem 5: Transform
20:15
Practice Problems
24:08
Practice Problem 6: Transform
24:09
Practice Problem 7: Transform
29:27
Practice Problems
33:08
Practice Problem 8: Transform
33:09
Practice Problem 9: Transform
35:23
Section 7: Carboxylic Acids
Carboxylic Acids

1h 17m 51s

Intro
0:00
Review Reactions of Ketone/Aldehyde
0:06
Carbonyl Reactivity
0:07
Nu: = Hydride (Reduction)
1:37
Nu: = Grignard
2:08
Review Reactions of Ketone/Aldehyde
2:53
Nu: = Alcohol
2:54
Nu: = Amine
3:46
Carboxylic Acids and Their Derivatives
4:37
Carboxylic Acids and Their Derivatives
4:38
Ketone vs. Ester Reactivity
6:33
Ketone Reactivity
6:34
Ester Reactivity
6:55
Carboxylic Acids and Their Derivatives
7:30
Acid Halide, Anhydride, Ester, Amide, and Nitrile
7:43
General Reactions of Acarboxylic Acid Derivatives
9:22
General Reactions of Acarboxylic Acid Derivatives
9:23
Physical Properties of Carboxylic Acids
12:16
Acetic Acid
12:17
Carboxylic Acids
15:46
Aciditiy of Carboxylic Acids, RCO₂H
17:45
Alcohol
17:46
Carboxylic Acid
19:21
Aciditiy of Carboxylic Acids, RCO₂H
21:31
Aciditiy of Carboxylic Acids, RCO₂H
21:32
Aciditiy of Carboxylic Acids, RCO₂H
24:48
Example: Which is the Stronger Acid?
24:49
Aciditiy of Carboxylic Acids, RCO₂H
30:06
Inductive Effects Decrease with Distance
30:07
Preparation of Carboxylic Acids, RCO₂H
31:55
A) By Oxidation
31:56
Preparation of Carboxylic Acids, RCO₂H
34:37
Oxidation of Alkenes/Alkynes - Ozonolysis
34:38
Preparation of Carboxylic Acids, RCO₂H
36:17
B) Preparation of RCO₂H from Organometallic Reagents
36:18
Preparation of Carboxylic Acids, RCO₂H
38:02
Example: Preparation of Carboxylic Acids
38:03
Preparation of Carboxylic Acids, RCO₂H
40:38
C) Preparation of RCO₂H by Hydrolysis of Carboxylic Acid Derivatives
40:39
Hydrolysis Mechanism
42:19
Hydrolysis Mechanism
42:20
Mechanism: Acyl Substitution (Addition/Elimination)
43:05
Hydrolysis Mechanism
47:27
Substitution Reaction
47:28
RO is Bad LG for SN1/SN2
47:39
RO is okay LG for Collapse of CTI
48:31
Hydrolysis Mechanism
50:07
Base-promoted Ester Hydrolysis (Saponification)
50:08
Applications of Carboxylic Acid Derivatives:
53:10
Saponification Reaction
53:11
Ester Hydrolysis
57:15
Acid-Catalyzed Mechanism
57:16
Ester Hydrolysis Requires Acide or Base
1:03:06
Ester Hydrolysis Requires Acide or Base
1:03:07
Nitrile Hydrolysis
1:05:22
Nitrile Hydrolysis
1:05:23
Nitrile Hydrolysis Mechanism
1:06:53
Nitrile Hydrolysis Mechanism
1:06:54
Use of Nitriles in Synthesis
1:12:39
Example: Nitirles in Synthesis
1:12:40
Carboxylic Acid Derivatives

1h 21m 4s

Intro
0:00
Carboxylic Acid Derivatives
0:05
Carboxylic Acid Derivatives
0:06
General Structure
1:00
Preparation of Carboxylic Acid Derivatives
1:19
Which Carbonyl is the Better E+?
1:20
Inductive Effects
1:54
Resonance
3:23
Preparation of Carboxylic Acid Derivatives
6:52
Which is Better E+, Ester or Acid Chloride?
6:53
Inductive Effects
7:02
Resonance
7:20
Preparation of Carboxylic Acid Derivatives
10:45
Which is Better E+, Carboxylic Acid or Anhydride?
10:46
Inductive Effects & Resonance
11:00
Overall: Order of Electrophilicity and Leaving Group
14:49
Order of Electrophilicity and Leaving Group
14:50
Example: Acid Chloride
16:26
Example: Carboxylate
19:17
Carboxylic Acid Derivative Interconversion
20:53
Carboxylic Acid Derivative Interconversion
20:54
Preparation of Acid Halides
24:31
Preparation of Acid Halides
24:32
Preparation of Anhydrides
25:45
A) Dehydration of Acids (For Symmetrical Anhydride)
25:46
Preparation of Anhydrides
27:29
Example: Dehydration of Acids
27:30
Preparation of Anhydrides
29:16
B) From an Acid Chloride (To Make Mixed Anhydride)
29:17
Mechanism
30:03
Preparation of Esters
31:53
A) From Acid Chloride or Anhydride
31:54
Preparation of Esters
33:48
B) From Carboxylic Acids (Fischer Esterification)
33:49
Mechanism
36:55
Preparations of Esters
41:38
Example: Predict the Product
41:39
Preparation of Esters
43:17
C) Transesterification
43:18
Mechanism
45:17
Preparation of Esters
47:58
D) SN2 with Carboxylate
47:59
Mechanism: Diazomethane
49:28
Preparation of Esters
51:01
Example: Transform
51:02
Preparation of Amides
52:27
A) From an Acid Cl or Anhydride
52:28
Preparations of Amides
54:47
B) Partial Hydrolysis of Nitriles
54:48
Preparation of Amides
56:11
Preparation of Amides: Find Alternate Path
56:12
Preparation of Amides
59:04
C) Can't be Easily Prepared from RCO₂H Directly
59:05
Reactions of Carboxylic Acid Derivatives with Nucleophiles
1:01:41
A) Hydride Nu: Review
1:01:42
A) Hydride Nu: Sodium Borohydride + Ester
1:02:43
Reactions of Carboxylic Acid Derivatives with Nucleophiles
1:03:57
Lithium Aluminum Hydride (LAH)
1:03:58
Mechanism
1:04:29
Summary of Hydride Reductions
1:07:09
Summary of Hydride Reductions 1
1:07:10
Summary of Hydride Reductions 2
1:07:36
Hydride Reduction of Amides
1:08:12
Hydride Reduction of Amides Mechanism
1:08:13
Reaction of Carboxylic Acid Derivatives with Organometallics
1:12:04
Review 1
1:12:05
Review 2
1:12:50
Reaction of Carboxylic Acid Derivatives with Organometallics
1:14:22
Example: Lactone
1:14:23
Special Hydride Nu: Reagents
1:16:34
Diisobutylaluminum Hydride
1:16:35
Example
1:17:25
Other Special Hydride
1:18:41
Addition of Organocuprates to Acid Chlorides
1:19:07
Addition of Organocuprates to Acid Chlorides
1:19:08
Section 8: Enols & Enolates
Enols and Enolates, Part 1

1h 26m 22s

Intro
0:00
Enols and Enolates
0:09
The Carbonyl
0:10
Keto-Enol Tautomerization
1:17
Keto-Enol Tautomerization Mechanism
2:28
Tautomerization Mechanism (2 Steps)
2:29
Keto-Enol Tautomerization Mechanism
5:15
Reverse Reaction
5:16
Mechanism
6:07
Formation of Enolates
7:27
Why is a Ketone's α H's Acidic?
7:28
Formation of Other Carbanions
10:05
Alkyne
10:06
Alkane and Alkene
10:53
Formation of an Enolate: Choice of Base
11:27
Example: Choice of Base
11:28
Formation of an Enolate: Choice of Base
13:56
Deprotonate, Stronger Base, and Lithium Diisopropyl Amide (LDA)
13:57
Formation of an Enolate: Choice of Base
15:48
Weaker Base & 'Active' Methylenes
15:49
Why Use NaOEt instead of NaOH?
19:01
Other Acidic 'α' Protons
20:30
Other Acidic 'α' Protons
20:31
Why is an Ester Less Acidic than a Ketone?
24:10
Other Acidic 'α' Protons
25:19
Other Acidic 'α' Protons Continue
25:20
How are Enolates Used
25:54
Enolates
25:55
Possible Electrophiles
26:21
Alkylation of Enolates
27:56
Alkylation of Enolates
27:57
Resonance Form
30:03
α-Halogenation
32:17
α-Halogenation
32:18
Iodoform Test for Methyl Ketones
33:47
α-Halogenation
35:55
Acid-Catalyzed
35:57
Mechanism: 1st Make Enol (2 Steps)
36:14
Whate Other Eloctrophiles ?
39:17
Aldol Condensation
39:38
Aldol Condensation
39:39
Aldol Mechanism
41:26
Aldol Mechanism: In Base, Deprotonate First
41:27
Aldol Mechanism
45:28
Mechanism for Loss of H₂O
45:29
Collapse of CTI and β-elimination Mechanism
47:51
Loss of H₂0 is not E2!
48:39
Aldol Summary
49:53
Aldol Summary
49:54
Base-Catalyzed Mechanism
52:34
Acid-Catalyzed Mechansim
53:01
Acid-Catalyzed Aldol Mechanism
54:01
First Step: Make Enol
54:02
Acid-Catalyzed Aldol Mechanism
56:54
Loss of H₂0 (β elimination)
56:55
Crossed/Mixed Aldol
1:00:55
Crossed/Mixed Aldol & Compound with α H's
1:00:56
Ketone vs. Aldehyde
1:02:30
Crossed/Mixed Aldol & Compound with α H's Continue
1:03:10
Crossed/Mixed Aldol
1:05:21
Mixed Aldol: control Using LDA
1:05:22
Crossed/Mixed Aldol Retrosynthesis
1:08:53
Example: Predic Aldol Starting Material (Aldol Retrosyntheiss)
1:08:54
Claisen Condensation
1:12:54
Claisen Condensation (Aldol on Esters)
1:12:55
Claisen Condensation
1:19:52
Example 1: Claisen Condensation
1:19:53
Claisen Condensation
1:22:48
Example 2: Claisen Condensation
1:22:49
Enols and Enolates, Part 2

50m 57s

Intro
0:00
Conjugate Additions
0:06
α, β-unsaturated Carbonyls
0:07
Conjugate Additions
1:50
'1,2-addition'
1:51
'1,-4-addition' or 'Conjugate Addition'
2:24
Conjugate Additions
4:53
Why can a Nu: Add to this Alkene?
4:54
Typical Alkene
5:09
α, β-unsaturated Alkene
5:39
Electrophilic Alkenes: Michael Acceptors
6:35
Other 'Electrophilic' Alkenes (Called 'Michael Acceptors)
6:36
1,4-Addition of Cuprates (R2CuLi)
8:29
1,4-Addition of Cuprates (R2CuLi)
8:30
1,4-Addition of Cuprates (R2CuLi)
11:23
Use Cuprates in Synthesis
11:24
Preparation of Cuprates
12:25
Prepare Organocuprate From Organolithium
12:26
Cuprates Also Do SN2 with RX E+ (Not True for RMgX, RLi)
13:06
1,4-Addition of Enolates: Michael Reaction
13:50
1,4-Addition of Enolates: Michael Reaction
13:51
Mechanism
15:57
1,4-Addition of Enolates: Michael Reaction
18:47
Example: 1,4-Addition of Enolates
18:48
1,4-Addition of Enolates: Michael Reaction
21:02
Michael Reaction, Followed by Intramolecular Aldol
21:03
Mechanism of the Robinson Annulation
24:26
Mechanism of the Robinson Annulation
24:27
Enols and Enolates: Advanced Synthesis Topics
31:10
Stablized Enolates and the Decarboxylation Reaction
31:11
Mechanism: A Pericyclic Reaction
32:08
Enols and Enolates: Advanced Synthesis Topics
33:32
Example: Advance Synthesis
33:33
Enols and Enolates: Advanced Synthesis Topics
36:10
Common Reagents: Diethyl Malonate
36:11
Common Reagents: Ethyl Acetoacetate
37:27
Enols and Enolates: Advanced Synthesis Topics
38:06
Example: Transform
38:07
Advanced Synthesis Topics: Enamines
41:52
Enamines
41:53
Advanced Synthesis Topics: Enamines
43:06
Reaction with Ketone/Aldehyde
43:07
Example
44:08
Advanced Synthesis Topics: Enamines
45:31
Example: Use Enamines as Nu: (Like Enolate)
45:32
Advanced Synthesis Topics: Enamines
47:56
Example
47:58
Section 9: Aromatic Compounds
Aromatic Compounds: Structure

1h 59s

Intro
0:00
Aromatic Compounds
0:05
Benzene
0:06
3D Sketch
1:33
Features of Benzene
4:41
Features of Benzene
4:42
Aromatic Stability
6:41
Resonance Stabilization of Benzene
6:42
Cyclohexatriene
7:24
Benzene (Actual, Experimental)
8:11
Aromatic Stability
9:03
Energy Graph
9:04
Aromaticity Requirements
9:55
1) Cyclic and Planar
9:56
2) Contiguous p Orbitals
10:49
3) Satisfy Huckel's Rule
11:20
Example: Benzene
12:32
Common Aromatic Compounds
13:28
Example: Pyridine
13:29
Common Aromatic Compounds
16:25
Example: Furan
16:26
Common Aromatic Compounds
19:42
Example: Thiophene
19:43
Example: Pyrrole
20:18
Common Aromatic Compounds
21:09
Cyclopentadienyl Anion
21:10
Cycloheptatrienyl Cation
23:48
Naphthalene
26:04
Determining Aromaticity
27:28
Example: Which of the Following are Aromatic?
27:29
Molecular Orbital (MO) Theory
32:26
What's So Special About '4n + 2' Electrons?
32:27
π bond & Overlapping p Orbitals
32:53
Molecular Orbital (MO) Diagrams
36:56
MO Diagram: Benzene
36:58
Drawing MO Diagrams
44:26
Example: 3-Membered Ring
44:27
Example: 4-Membered Ring
46:04
Drawing MO Diagrams
47:51
Example: 5-Membered Ring
47:52
Example: 8-Membered Ring
49:32
Aromaticity and Reactivity
51:03
Example: Which is More Acidic?
51:04
Aromaticity and Reactivity
56:03
Example: Which has More Basic Nitrogen, Pyrrole or Pyridine?
56:04
Aromatic Compounds: Reactions, Part 1

1h 24m 4s

Intro
0:00
Reactions of Benzene
0:07
N/R as Alkenes
0:08
Substitution Reactions
0:50
Electrophilic Aromatic Substitution
1:24
Electrophilic Aromatic Substitution
1:25
Mechanism Step 1: Addition of Electrophile
2:08
Mechanism Step 2: Loss of H+
4:14
Electrophilic Aromatic Substitution on Substituted Benzenes
5:21
Electron Donating Group
5:22
Electron Withdrawing Group
8:02
Halogen
9:23
Effects of Electron-Donating Groups (EDG)
10:23
Effects of Electron-Donating Groups (EDG)
10:24
What Effect Does EDG (OH) Have?
11:40
Reactivity
13:03
Regioselectivity
14:07
Regioselectivity: EDG is o/p Director
14:57
Prove It! Add E+ and Look at Possible Intermediates
14:58
Is OH Good or Bad?
17:38
Effects of Electron-Withdrawing Groups (EWG)
20:20
What Effect Does EWG Have?
20:21
Reactivity
21:28
Regioselectivity
22:24
Regioselectivity: EWG is a Meta Director
23:23
Prove It! Add E+ and Look at Competing Intermediates
23:24
Carbocation: Good or Bad?
26:01
Effects of Halogens on EAS
28:33
Inductive Withdrawal of e- Density vs. Resonance Donation
28:34
Summary of Substituent Effects on EAS
32:33
Electron Donating Group
32:34
Electron Withdrawing Group
33:37
Directing Power of Substituents
34:35
Directing Power of Substituents
34:36
Example
36:41
Electrophiles for Electrophilic Aromatic Substitution
38:43
Reaction: Halogenation
38:44
Electrophiles for Electrophilic Aromatic Substitution
40:27
Reaction: Nitration
40:28
Electrophiles for Electrophilic Aromatic Substitution
41:45
Reaction: Sulfonation
41:46
Electrophiles for Electrophilic Aromatic Substitution
43:19
Reaction: Friedel-Crafts Alkylation
43:20
Electrophiles for Electrophilic Aromatic Substitution
45:43
Reaction: Friedel-Crafts Acylation
45:44
Electrophilic Aromatic Substitution: Nitration
46:52
Electrophilic Aromatic Substitution: Nitration
46:53
Mechanism
48:56
Nitration of Aniline
52:40
Nitration of Aniline Part 1
52:41
Nitration of Aniline Part 2: Why?
54:12
Nitration of Aniline
56:10
Workaround: Protect Amino Group as an Amide
56:11
Electrophilic Aromatic Substitution: Sulfonation
58:16
Electrophilic Aromatic Substitution: Sulfonation
58:17
Example: Transform
59:25
Electrophilic Aromatic Substitution: Friedel-Crafts Alkylation
1:02:24
Electrophilic Aromatic Substitution: Friedel-Crafts Alkylation
1:02:25
Example & Mechanism
1:03:37
Friedel-Crafts Alkylation Drawbacks
1:05:48
A) Can Over-React (Dialkylation)
1:05:49
Friedel-Crafts Alkylation Drawbacks
1:08:21
B) Carbocation Can Rearrange
1:08:22
Mechanism
1:09:33
Friedel-Crafts Alkylation Drawbacks
1:13:35
Want n-Propyl? Use Friedel-Crafts Acylation
1:13:36
Reducing Agents
1:16:45
Synthesis with Electrophilic Aromatic Substitution
1:18:45
Example: Transform
1:18:46
Synthesis with Electrophilic Aromatic Substitution
1:20:59
Example: Transform
1:21:00
Aromatic Compounds: Reactions, Part 2

59m 10s

Intro
0:00
Reagents for Electrophilic Aromatic Substitution
0:07
Reagents for Electrophilic Aromatic Substitution
0:08
Preparation of Diazonium Salt
2:12
Preparation of Diazonium Salt
2:13
Reagents for Sandmeyer Reactions
4:14
Reagents for Sandmeyer Reactions
4:15
Apply Diazonium Salt in Synthesis
6:20
Example: Transform
6:21
Apply Diazonium Salt in Synthesis
9:14
Example: Synthesize Following Target Molecule from Benzene or Toluene
9:15
Apply Diazonium Salt in Synthesis
14:56
Example: Transform
14:57
Reactions of Aromatic Substituents
21:56
A) Reduction Reactions
21:57
Reactions of Aromatic Substituents
23:24
B) Oxidations of Arenes
23:25
Benzylic [ox] Even Breaks C-C Bonds!
25:05
Benzylic Carbon Can't Be Quaternary
25:55
Reactions of Aromatic Substituents
26:21
Example
26:22
Review of Benzoic Acid Synthesis
27:34
Via Hydrolysis
27:35
Via Grignard
28:20
Reactions of Aromatic Substituents
29:15
C) Benzylic Halogenation
29:16
Radical Stabilities
31:55
N-bromosuccinimide (NBS)
32:23
Reactions of Aromatic Substituents
33:08
D) Benzylic Substitutions
33:09
Reactions of Aromatic Side Chains
37:08
Example: Transform
37:09
Nucleophilic Aromatic Substitution
43:13
Nucleophilic Aromatic Substitution
43:14
Nucleophilic Aromatic Substitution
47:08
Example
47:09
Mechanism
48:00
Nucleophilic Aromatic Substitution
50:43
Example
50:44
Nucleophilic Substitution: Benzyne Mechanism
52:46
Nucleophilic Substitution: Benzyne Mechanism
52:47
Nucleophilic Substitution: Benzyne Mechanism
57:31
Example: Predict Product
57:32
Section 10: Dienes & Amines
Conjugated Dienes

1h 9m 12s

Intro
0:00
Conjugated Dienes
0:08
Conjugated π Bonds
0:09
Diene Stability
2:00
Diene Stability: Cumulated
2:01
Diene Stability: Isolated
2:37
Diene Stability: Conjugated
2:51
Heat of Hydrogenation
3:00
Allylic Carbocations and Radicals
5:15
Allylic Carbocations and Radicals
5:16
Electrophilic Additions to Dienes
7:00
Alkenes
7:01
Unsaturated Ketone
7:47
Electrophilic Additions to Dienes
8:28
Conjugated Dienes
8:29
Electrophilic Additions to Dienes
9:46
Mechanism (2-Steps): Alkene
9:47
Electrophilic Additions to Dienes
11:40
Mechanism (2-Steps): Diene
11:41
1,2 'Kinetic' Product
13:08
1,4 'Thermodynamic' Product
14:47
E vs. POR Diagram
15:50
E vs. POR Diagram
15:51
Kinetic vs. Thermodynamic Control
21:56
Kinetic vs. Thermodynamic Control
21:57
How? Reaction is Reversible!
23:51
1,2 (Less Stable product)
23:52
1,4 (More Stable Product)
25:16
Diels Alder Reaction
26:34
Diels Alder Reaction
26:35
Dienophiles (E+)
29:23
Dienophiles (E+)
29:24
Alkyne Diels-Alder Example
30:48
Example: Alkyne Diels-Alder
30:49
Diels-Alder Reaction: Dienes (Nu:)
32:22
Diels-Alder ReactionL Dienes (Nu:)
32:23
Diels-Alder Reaction: Dienes
33:51
Dienes Must Have 's-cis' Conformation
33:52
Example
35:25
Diels-Alder Reaction with Cyclic Dienes
36:08
Cyclic Dienes are Great for Diels-Alder Reaction
36:09
Cyclopentadiene
37:10
Diels-Alder Reaction: Bicyclic Products
40:50
Endo vs. Exo Terminology: Norbornane & Bicyclo Heptane
40:51
Example: Bicyclo Heptane
42:29
Diels-Alder Reaction with Cyclic Dienes
44:15
Example
44:16
Stereochemistry of the Diels-Alder Reaction
47:39
Stereochemistry of the Diels-Alder Reaction
47:40
Example
48:08
Stereochemistry of the Diels-Alder Reaction
50:21
Example
50:22
Regiochemistry of the Diels-Alder Reaction
52:42
Rule: 1,2-Product Preferred Over 1,3-Product
52:43
Regiochemistry of the Diels-Alder Reaction
54:18
Rule: 1,4-Product Preferred Over 1,3-Product
54:19
Regiochemistry of the Diels-Alder Reaction
55:02
Why 1,2-Product or 1,4-Product Favored?
55:03
Example
56:11
Diels-Alder Reaction
58:06
Example: Predict
58:07
Diels-Alder Reaction
1:01:27
Explain Why No Diels-Alder Reaction Takes Place in This Case
1:01:28
Diels-Alder Reaction
1:03:09
Example: Predict
1:03:10
Diels-Alder Reaction: Synthesis Problem
1:05:39
Diels-Alder Reaction: Synthesis Problem
1:05:40
Pericyclic Reactions and Molecular Orbital (MO) Theory

1h 21m 31s

Intro
0:00
Pericyclic Reactions
0:05
Pericyclic Reactions
0:06
Electrocyclic Reactions
1:19
Electrocyclic Reactions
1:20
Electrocyclic Reactions
3:13
Stereoselectivity
3:14
Electrocyclic Reactions
8:10
Example: Predict
8:11
Sigmatropic Rearrangements
12:29
Sigmatropic Rearrangements
12:30
Cope Rearrangement
14:44
Sigmatropic Rearrangements
16:44
Claisen Rearrangement 1
16:45
Claisen Rearrangement 2
17:46
Cycloaddition Reactions
19:22
Diels-Alder
19:23
1,3-Dipolar Cycloaddition
20:32
Cycloaddition Reactions: Stereochemistry
21:58
Cycloaddition Reactions: Stereochemistry
21:59
Cycloaddition Reactions: Heat or Light?
26:00
4+2 Cycloadditions
26:01
2+2 Cycloadditions
27:23
Molecular Orbital (MO) Theory of Chemical Reactions
29:26
Example 1: Molecular Orbital Theory of Bonding
29:27
Molecular Orbital (MO) Theory of Chemical Reactions
31:59
Example 2: Molecular Orbital Theory of Bonding
32:00
Molecular Orbital (MO) Theory of Chemical Reactions
33:33
MO Theory of Aromaticity, Huckel's Rule
33:34
Molecular Orbital (MO) Theory of Chemical Reactions
36:43
Review: Molecular Orbital Theory of Conjugated Systems
36:44
Molecular Orbital (MO) Theory of Chemical Reactions
44:56
Review: Molecular Orbital Theory of Conjugated Systems
44:57
Molecular Orbital (MO) Theory of Chemical Reactions
46:54
Review: Molecular Orbital Theory of Conjugated Systems
46:55
Molecular Orbital (MO) Theory of Chemical Reactions
48:36
Frontier Molecular Orbitals are Involved in Reactions
48:37
Examples
50:20
MO Theory of Pericyclic Reactions: The Woodward-Hoffmann Rules
51:51
Heat-promoted Pericyclic Reactions and Light-promoted Pericyclic Reactions
51:52
MO Theory of Pericyclic Reactions: The Woodward-Hoffmann Rules
53:42
Why is a [4+2] Cycloaddition Thermally Allowed While the [2+2] is Not?
53:43
MO Theory of Pericyclic Reactions: The Woodward-Hoffmann Rules
56:51
Why is a [2+2] Cycloaddition Photochemically Allowed?
56:52
Pericyclic Reaction Example I
59:16
Pericyclic Reaction Example I
59:17
Pericyclic Reaction Example II
1:07:40
Pericyclic Reaction Example II
1:07:41
Pericyclic Reaction Example III: Vitamin D - The Sunshine Vitamin
1:14:22
Pericyclic Reaction Example III: Vitamin D - The Sunshine Vitamin
1:14:23
Amines

34m 58s

Intro
0:00
Amines: Properties and Reactivity
0:04
Compare Amines to Alcohols
0:05
Amines: Lower Boiling Point than ROH
0:55
1) RNH₂ Has Lower Boiling Point than ROH
0:56
Amines: Better Nu: Than ROH
2:22
2) RNH₂ is a Better Nucleophile than ROH Example 1
2:23
RNH₂ is a Better Nucleophile than ROH Example 2
3:08
Amines: Better Nu: than ROH
3:47
Example
3:48
Amines are Good Bases
5:41
3) RNH₂ is a Good Base
5:42
Amines are Good Bases
7:06
Example 1
7:07
Example 2: Amino Acid
8:27
Alkyl vs. Aryl Amines
9:56
Example: Which is Strongest Base?
9:57
Alkyl vs. Aryl Amines
14:55
Verify by Comparing Conjugate Acids
14:56
Reaction of Amines
17:42
Reaction with Ketone/Aldehyde: 1° Amine (RNH₂)
17:43
Reaction of Amines
18:48
Reaction with Ketone/Aldehyde: 2° Amine (R2NH)
18:49
Use of Enamine: Synthetic Equivalent of Enolate
20:08
Use of Enamine: Synthetic Equivalent of Enolate
20:09
Reaction of Amines
24:10
Hofmann Elimination
24:11
Hofmann Elimination
26:16
Kinetic Product
26:17
Structure Analysis Using Hofmann Elimination
28:22
Structure Analysis Using Hofmann Elimination
28:23
Biological Activity of Amines
30:30
Adrenaline
31:07
Mescaline (Peyote Alkaloid)
31:22
Amino Acids, Amide, and Protein
32:14
Biological Activity of Amines
32:50
Morphine (Opium Alkaloid)
32:51
Epibatidine (Poison Dart Frog)
33:28
Nicotine
33:48
Choline (Nerve Impulse)
34:03
Section 11: Biomolecules & Polymers
Biomolecules

1h 53m 20s

Intro
0:00
Carbohydrates
1:11
D-glucose Overview
1:12
D-glucose: Cyclic Form (6-membered ring)
4:31
Cyclic Forms of Glucose: 6-membered Ring
8:24
α-D-glucopyranose & β-D-glucopyranose
8:25
Formation of a 5-Membered Ring
11:05
D-glucose: Formation of a 5-Membered Ring
11:06
Cyclic Forms of Glucose: 5-membered Ring
12:37
α-D-glucofuranose & β-D-glucofuranose
12:38
Carbohydrate Mechanism
14:03
Carbohydrate Mechanism
14:04
Reactions of Glucose: Acetal Formation
21:35
Acetal Formation: Methyl-α-D-glucoside
21:36
Hemiacetal to Acetal: Overview
24:58
Mechanism for Formation of Glycosidic Bond
25:51
Hemiacetal to Acetal: Mechanism
25:52
Formation of Disaccharides
29:34
Formation of Disaccharides
29:35
Some Polysaccharides: Starch
31:33
Amylose & Amylopectin
31:34
Starch: α-1,4-glycosidic Bonds
32:22
Properties of Starch Molecule
33:21
Some Polysaccharides: Cellulose
33:59
Cellulose: β-1,4-glycosidic bonds
34:00
Properties of Cellulose
34:59
Other Sugar-Containing Biomolecules
35:50
Ribonucleoside (RNA)
35:51
Deoxyribonucleoside (DMA)
36:59
Amino Acids & Proteins
37:32
α-amino Acids: Structure & Stereochemistry
37:33
Making a Protein (Condensation)
42:46
Making a Protein (Condensation)
42:47
Peptide Bond is Planar (Amide Resonance)
44:55
Peptide Bond is Planar (Amide Resonance)
44:56
Protein Functions
47:49
Muscle, Skin, Bones, Hair Nails
47:50
Enzymes
49:10
Antibodies
49:44
Hormones, Hemoglobin
49:58
Gene Regulation
50:20
Various Amino Acid Side Chains
50:51
Nonpolar
50:52
Polar
51:15
Acidic
51:24
Basic
51:55
Amino Acid Table
52:22
Amino Acid Table
52:23
Isoelectric Point (pI)
53:43
Isoelectric Point (pI) of Glycine
53:44
Isoelectric Point (pI) of Glycine: pH 11
56:42
Isoelectric Point (pI) of Glycine: pH 1
57:20
Isoelectric Point (pI), cont.
58:05
Asparatic Acid
58:06
Histidine
1:00:28
Isoelectric Point (pI), cont.
1:02:54
Example: What is the Net Charge of This Tetrapeptide at pH 6.0?
1:02:55
Nucleic Acids: Ribonucleosides
1:10:32
Nucleic Acids: Ribonucleosides
1:10:33
Nucleic Acids: Ribonucleotides
1:11:48
Ribonucleotides: 5' Phosphorylated Ribonucleosides
1:11:49
Ribonucleic Acid (RNA) Structure
1:12:35
Ribonucleic Acid (RNA) Structure
1:12:36
Nucleic Acids: Deoxyribonucleosides
1:14:08
Nucleic Acids: Deoxyribonucleosides
1:14:09
Deoxythymidine (T)
1:14:36
Nucleic Acids: Base-Pairing
1:15:17
Nucleic Acids: Base-Pairing
1:15:18
Double-Stranded Structure of DNA
1:18:16
Double-Stranded Structure of DNA
1:18:17
Model of DNA
1:19:40
Model of DNA
1:19:41
Space-Filling Model of DNA
1:20:46
Space-Filling Model of DNA
1:20:47
Function of RNA and DNA
1:23:06
DNA & Transcription
1:23:07
RNA & Translation
1:24:22
Genetic Code
1:25:09
Genetic Code
1:25:10
Lipids/Fats/Triglycerides
1:27:10
Structure of Glycerol
1:27:43
Saturated & Unsaturated Fatty Acids
1:27:51
Triglyceride
1:28:43
Unsaturated Fats: Lower Melting Points (Liquids/Oils)
1:29:15
Saturated Fat
1:29:16
Unsaturated Fat
1:30:10
Partial Hydrogenation
1:32:05
Saponification of Fats
1:35:11
Saponification of Fats
1:35:12
History of Soap
1:36:50
Carboxylate Salts form Micelles in Water
1:41:02
Carboxylate Salts form Micelles in Water
1:41:03
Cleaning Power of Micelles
1:42:21
Cleaning Power of Micelles
1:42:22
3-D Image of a Micelle
1:42:58
3-D Image of a Micelle
1:42:59
Synthesis of Biodiesel
1:44:04
Synthesis of Biodiesel
1:44:05
Phosphoglycerides
1:47:54
Phosphoglycerides
1:47:55
Cell Membranes Contain Lipid Bilayers
1:48:41
Cell Membranes Contain Lipid Bilayers
1:48:42
Bilayer Acts as Barrier to Movement In/Out of Cell
1:50:24
Bilayer Acts as Barrier to Movement In/Out of Cell
1:50:25
Organic Chemistry Meets Biology… Biochemistry!
1:51:12
Organic Chemistry Meets Biology… Biochemistry!
1:51:13
Polymers

45m 47s

Intro
0:00
Polymers
0:05
Monomer to Polymer: Vinyl Chloride to Polyvinyl Chloride
0:06
Polymer Properties
1:32
Polymer Properties
1:33
Natural Polymers: Rubber
2:30
Vulcanization
2:31
Natural Polymers: Polysaccharides
4:55
Example: Starch
4:56
Example: Cellulose
5:45
Natural Polymers: Proteins
6:07
Example: Keratin
6:08
DNA Strands
7:15
DNA Strands
7:16
Synthetic Polymers
8:30
Ethylene & Polyethylene: Lightweight Insulator & Airtight Plastic
8:31
Synthetic Organic Polymers
12:22
Polyethylene
12:28
Polyvinyl Chloride (PVC)
12:54
Polystyrene
13:28
Polyamide
14:34
Polymethyl Methacrylate
14:57
Kevlar
15:25
Synthetic Material Examples
16:30
How are Polymers Made?
21:00
Chain-growth Polymers Additions to Alkenes can be Radical, Cationic or Anionic
21:01
Chain Branching
22:34
Chain Branching
22:35
Special Reaction Conditions Prevent Branching
24:28
Ziegler-Natta Catalyst
24:29
Chain-Growth by Cationic Polymerization
27:35
Chain-Growth by Cationic Polymerization
27:36
Chain-Growth by Anionic Polymerization
29:35
Chain-Growth by Anionic Polymerization
29:36
Step-Growth Polymerization: Polyamides
32:16
Step-Growth Polymerization: Polyamides
32:17
Step-Growth Polymerization: Polyesters
34:23
Step-Growth Polymerization: Polyesters
34:24
Step-Growth Polymerization: Polycarbonates
35:56
Step-Growth Polymerization: Polycarbonates
35:57
Step-Growth Polymerization: Polyurethanes
37:18
Step-Growth Polymerization: Polyurethanes
37:19
Modifying Polymer Properties
39:35
Glass Transition Temperature
40:04
Crosslinking
40:42
Copolymers
40:58
Additives: Stabilizers
42:08
Additives: Flame Retardants
43:03
Additives: Plasticizers
43:41
Additives: Colorants
44:54
Section 12: Organic Synthesis
Organic Synthesis Strategies

2h 20m 24s

Intro
0:00
Organic Synthesis Strategies
0:15
Goal
0:16
Strategy
0:29
Example of a RetroSynthesis
1:30
Finding Starting Materials for Target Molecule
1:31
Synthesis Using Starting Materials
4:56
Synthesis of Alcohols by Functional Group Interconversion (FGI)
6:00
Synthesis of Alcohols by Functional Group Interconversion Overview
6:01
Alcohols by Reduction
7:43
Ketone to Alcohols
7:45
Aldehyde to Alcohols
8:26
Carboxylic Acid Derivative to Alcohols
8:36
Alcohols by Hydration of Alkenes
9:28
Hydration of Alkenes Using H₃O⁺
9:29
Oxymercuration-Demercuration
10:35
Hydroboration Oxidation
11:02
Alcohols by Substitution
11:42
Primary Alkyl Halide to Alcohols Using NaOH
11:43
Secondary Alkyl Halide to Alcohols Using Sodium Acetate
13:07
Tertiary Alkyl Halide to Alcohols Using H₂O
15:08
Synthesis of Alcohols by Forming a New C-C Bond
15:47
Recall: Alcohol & RMgBr
15:48
Retrosynthesis
17:28
Other Alcohol Disconnections
19:46
19:47
Synthesis Using PhMGgBr: Example 2
23:05
Synthesis of Alkyl Halides
26:06
Synthesis of Alkyl Halides Overview
26:07
Synthesis of Alkyl Halides by Free Radical Halogenation
27:04
Synthesis of Alkyl Halides by Free Radical Halogenation
27:05
Synthesis of Alkyl Halides by Substitution
29:06
Alcohol to Alkyl Halides Using HBr or HCl
29:07
Alcohol to Alkyl Halides Using SOCl₂
30:57
Alcohol to Alkyl Halides Using PBr₃ and Using P, I₂
31:03
Synthesis of Alkyl Halides by Addition
32:02
Alkene to Alkyl Halides Using HBr
32:03
Alkene to Alkyl Halides Using HBr & ROOR (Peroxides)
32:35
Example: Synthesis of Alkyl Halide
34:18
Example: Synthesis of Alkyl Halide
34:19
Synthesis of Ethers
39:25
Synthesis of Ethers
39:26
Example: Synthesis of an Ether
41:12
Synthesize TBME (t-butyl methyl ether) from Alcohol Starting Materials
41:13
Synthesis of Amines
46:05
Synthesis of Amines
46:06
Gabriel Synthesis of Amines
47:57
Gabriel Synthesis of Amines
47:58
Amines by SN2 with Azide Nu:
49:50
Amines by SN2 with Azide Nu:
49:51
Amines by SN2 with Cyanide Nu:
50:31
Amines by SN2 with Cyanide Nu:
50:32
Amines by Reduction of Amides
51:30
Amines by Reduction of Amides
51:31
Reductive Amination of Ketones/Aldehydes
52:42
Reductive Amination of Ketones/Aldehydes
52:43
Example : Synthesis of an Amine
53:47
Example 1: Synthesis of an Amine
53:48
Example 2: Synthesis of an Amine
56:16
Synthesis of Alkenes
58:20
Synthesis of Alkenes Overview
58:21
Synthesis of Alkenes by Elimination
59:04
Synthesis of Alkenes by Elimination Using NaOH & Heat
59:05
Synthesis of Alkenes by Elimination Using H₂SO₄ & Heat
59:57
Synthesis of Alkenes by Reduction
1:02:05
Alkyne to Cis Alkene
1:02:06
Alkyne to Trans Alkene
1:02:56
Synthesis of Alkenes by Wittig Reaction
1:03:46
Synthesis of Alkenes by Wittig Reaction
1:03:47
Retrosynthesis of an Alkene
1:05:35
Example: Synthesis of an Alkene
1:06:57
Example: Synthesis of an Alkene
1:06:58
Making a Wittig Reagent
1:10:31
Synthesis of Alkynes
1:13:09
Synthesis of Alkynes
1:13:10
Synthesis of Alkynes by Elimination (FGI)
1:13:42
First Step: Bromination of Alkene
1:13:43
Second Step: KOH Heat
1:14:22
Synthesis of Alkynes by Alkylation
1:15:02
Synthesis of Alkynes by Alkylation
1:15:03
Retrosynthesis of an Alkyne
1:16:18
Example: Synthesis of an Alkyne
1:17:40
Example: Synthesis of an Alkyne
1:17:41
Synthesis of Alkanes
1:20:52
Synthesis of Alkanes
1:20:53
Synthesis of Aldehydes & Ketones
1:21:38
Oxidation of Alcohol Using PCC or Swern
1:21:39
Oxidation of Alkene Using 1) O₃, 2)Zn
1:22:42
Reduction of Acid Chloride & Nitrile Using DiBAL-H
1:23:25
Hydration of Alkynes
1:24:55
Synthesis of Ketones by Acyl Substitution
1:26:12
Reaction with R'₂CuLi
1:26:13
Reaction with R'MgBr
1:27:13
Synthesis of Aldehydes & Ketones by α-Alkylation
1:28:00
Synthesis of Aldehydes & Ketones by α-Alkylation
1:28:01
Retrosynthesis of a Ketone
1:30:10
Acetoacetate Ester Synthesis of Ketones
1:31:05
Acetoacetate Ester Synthesis of Ketones: Step 1
1:31:06
Acetoacetate Ester Synthesis of Ketones: Step 2
1:32:13
Acetoacetate Ester Synthesis of Ketones: Step 3
1:32:50
Example: Synthesis of a Ketone
1:34:11
Example: Synthesis of a Ketone
1:34:12
Synthesis of Carboxylic Acids
1:37:15
Synthesis of Carboxylic Acids
1:37:16
Example: Synthesis of a Carboxylic Acid
1:37:59
Example: Synthesis of a Carboxylic Acid (Option 1)
1:38:00
Example: Synthesis of a Carboxylic Acid (Option 2)
1:40:51
Malonic Ester Synthesis of Carboxylic Acid
1:42:34
Malonic Ester Synthesis of Carboxylic Acid: Step 1
1:42:35
Malonic Ester Synthesis of Carboxylic Acid: Step 2
1:43:36
Malonic Ester Synthesis of Carboxylic Acid: Step 3
1:44:01
Example: Synthesis of a Carboxylic Acid
1:44:53
Example: Synthesis of a Carboxylic Acid
1:44:54
Synthesis of Carboxylic Acid Derivatives
1:48:05
Synthesis of Carboxylic Acid Derivatives
1:48:06
Alternate Ester Synthesis
1:48:58
Using Fischer Esterification
1:48:59
Using SN2 Reaction
1:50:18
Using Diazomethane
1:50:56
Using 1) LDA, 2) R'-X
1:52:15
Practice: Synthesis of an Alkyl Chloride
1:53:11
Practice: Synthesis of an Alkyl Chloride
1:53:12
Patterns of Functional Groups in Target Molecules
1:59:53
Recall: Aldol Reaction
1:59:54
β-hydroxy Ketone Target Molecule
2:01:12
α,β-unsaturated Ketone Target Molecule
2:02:20
Patterns of Functional Groups in Target Molecules
2:03:15
Recall: Michael Reaction
2:03:16
Retrosynthesis: 1,5-dicarbonyl Target Molecule
2:04:07
Patterns of Functional Groups in Target Molecules
2:06:38
Recall: Claisen Condensation
2:06:39
Retrosynthesis: β-ketoester Target Molecule
2:07:30
2-Group Target Molecule Summary
2:09:03
2-Group Target Molecule Summary
2:09:04
Example: Synthesis of Epoxy Ketone
2:11:19
Synthesize the Following Target Molecule from Cyclohexanone: Part 1 - Retrosynthesis
2:11:20
Synthesize the Following Target Molecule from Cyclohexanone: Part 2 - Synthesis
2:14:10
Example: Synthesis of a Diketone
2:16:57
Synthesis of a Diketone: Step 1 - Retrosynthesis
2:16:58
Synthesis of a Diketone: Step 2 - Synthesis
2:18:51
Section 12: Organic Synthesis & Organic Analysis
Organic Analysis: Classical & Modern Methods

46m 46s

Intro
0:00
Organic Analysis: Classical Methods
0:17
Classical Methods for Identifying Chemicals
0:18
Organic Analysis: Classical Methods
2:21
When is Structure Identification Needed?
2:22
Organic Analysis: Classical Methods
6:17
Classical Methods of Structure Identification: Physical Appearance
6:18
Classical Methods of Structure Identification: Physical Constants
6:42
Organic Analysis: Classical Methods
7:37
Classical Methods of Structure Identification: Solubility Tests - Water
7:38
Organic Analysis: Classical Methods
10:51
Classical Methods of Structure Identification: Solubility Tests - 5% aq. HCl Basic FG (Amines)
10:52
Organic Analysis: Classical Methods
11:50
Classical Methods of Structure Identification: Solubility Tests - 5% aq. NaOH Acidic FG (Carboxylic Acids, Phenols)
11:51
Organic Analysis: Classical Methods
13:28
Classical Methods of Structure Identification: Solubility Tests - 5% aq. NaHCO3 Strongly Acidic FG (Carboxylic Acids)
13:29
Organic Analysis: Classical Methods
15:35
Classical Methods of Structure Identification: Solubility Tests - Insoluble in All of the Above
15:36
Organic Analysis: Classical Methods
16:49
Classical Methods of Structure Identification: Idoform Test for Methyl Ketones
16:50
Organic Analysis: Classical Methods
22:02
Classical Methods of Structure Identification: Tollens' Test or Fehling's Solution for Aldehydes
22:03
Organic Analysis: Classical Methods
25:01
Useful Application of Classical Methods: Glucose Oxidase on Glucose Test Strips
25:02
Organic Analysis: Classical Methods
26:26
Classical Methods of Structure Identification: Starch-iodide Test
26:27
Organic Analysis: Classical Methods
28:22
Classical Methods of Structure Identification: Lucas Reagent to Determine Primary/Secondary/Tertiary Alcohol
28:23
Organic Analysis: Classical Methods
31:35
Classical Methods of Structure Identification: Silver Nitrate Test for Alkyl Halides
31:36
Organic Analysis: Classical Methods
33:23
Preparation of Derivatives
33:24
Organic Analysis: Modern Methods
36:55
Modern Methods of Chemical Characterization
36:56
Organic Analysis: Modern Methods
40:36
Checklist for Manuscripts Submitted to the ACS Journal Organic Letters
40:37
Organic Analysis: Modern Methods
42:39
Checklist for Manuscripts Submitted to the ACS Journal Organic Letters
42:40
Analysis of Stereochemistry

1h 2m 52s

Intro
0:00
Chirality & Optical Activity
0:32
Levorotatory & Dextrorotatory
0:33
Example: Optically Active?
2:22
Example: Optically Active?
2:23
Measurement of Specific Rotation, [α]
5:09
Measurement of Specific Rotation, [α]
5:10
Example: Calculation of Specific Rotation
8:56
Example: Calculation of Specific Rotation
8:57
Variability of Specific Rotation, [α]
12:52
Variability of Specific Rotation, [α]
12:53
Other Measures of Optical Activity: ORD and CD
15:04
Optical Rotary Dispersion (ORD)
15:05
Circular Dischroism (CD)
18:32
Circular Dischroism (CD)
18:33
Mixtures of Enantiomers
20:16
Racemic Mixtures
20:17
Unequal Mixtures of Enantiomers
21:36
100% ee
22:48
0% ee
23:34
Example: Definition of ee?
24:00
Example: Definition of ee?
24:01
Analysis of Optical Purity: [α]
27:47
[α] Measurement Can Be Used for Known Compounds
27:48
Analysis of Optical Purity: [α]
34:30
NMR Methods Using a Chiral Derivatizing Agent (CDA): Mosher's Reagent
34:31
Analysis of Optical Purity: [α]
40:01
NMR Methods Using a Chiral Derivatizing Agent (CDA): CDA Salt Formation
40:02
Analysis of Optical Purity: Chromatography
42:46
Chiral Chromatography
42:47
Stereochemistry Analysis by NMR: J Values (Coupling Constant)
51:28
NMR Methods for Structure Determination
51:29
Stereochemistry Analysis by NRM: NOE
57:00
NOE - Nuclear Overhauser Effect ( 2D Versions: NOESY or ROESY)
57:01
Section 13: Spectroscopy
Infrared Spectroscopy, Part I

1h 4m

Intro
0:00
Infrared (IR) Spectroscopy
0:09
Introduction to Infrared (IR) Spectroscopy
0:10
Intensity of Absorption Is Proportional to Change in Dipole
3:08
IR Spectrum of an Alkane
6:08
Pentane
6:09
IR Spectrum of an Alkene
13:12
1-Pentene
13:13
IR Spectrum of an Alkyne
15:49
1-Pentyne
15:50
IR Spectrum of an Aromatic Compound
18:02
Methylbenzene
18:24
IR of Substituted Aromatic Compounds
24:04
IR of Substituted Aromatic Compounds
24:05
IR Spectrum of 1,2-Disubstituted Aromatic
25:30
1,2-dimethylbenzene
25:31
IR Spectrum of 1,3-Disubstituted Aromatic
27:15
1,3-dimethylbenzene
27:16
IR Spectrum of 1,4-Disubstituted Aromatic
28:41
1,4-dimethylbenzene
28:42
IR Spectrum of an Alcohol
29:34
1-pentanol
29:35
IR Spectrum of an Amine
32:39
1-butanamine
32:40
IR Spectrum of a 2° Amine
34:50
Diethylamine
34:51
IR Spectrum of a 3° Amine
35:47
Triethylamine
35:48
IR Spectrum of a Ketone
36:41
2-butanone
36:42
IR Spectrum of an Aldehyde
40:10
Pentanal
40:11
IR Spectrum of an Ester
42:38
Butyl Propanoate
42:39
IR Spectrum of a Carboxylic Acid
44:26
Butanoic Acid
44:27
Sample IR Correlation Chart
47:36
Sample IR Correlation Chart: Wavenumber and Functional Group
47:37
Predicting IR Spectra: Sample Structures
52:06
Example 1
52:07
Example 2
53:29
Example 3
54:40
Example 4
57:08
Example 5
58:31
Example 6
59:07
Example 7
1:00:52
Example 8
1:02:20
Infrared Spectroscopy, Part II

48m 34s

Intro
0:00
Interpretation of IR Spectra: a Basic Approach
0:05
Interpretation of IR Spectra: a Basic Approach
0:06
Other Peaks to Look for
3:39
Examples
5:17
Example 1
5:18
Example 2
9:09
Example 3
11:52
Example 4
14:03
Example 5
16:31
Example 6
19:31
Example 7
22:32
Example 8
24:39
IR Problems Part 1
28:11
IR Problem 1
28:12
IR Problem 2
31:14
IR Problem 3
32:59
IR Problem 4
34:23
IR Problem 5
35:49
IR Problem 6
38:20
IR Problems Part 2
42:36
IR Problem 7
42:37
IR Problem 8
44:02
IR Problem 9
45:07
IR Problems10
46:10
Nuclear Magnetic Resonance (NMR) Spectroscopy, Part I

1h 32m 14s

Intro
0:00
Purpose of NMR
0:14
Purpose of NMR
0:15
How NMR Works
2:17
How NMR Works
2:18
Information Obtained From a ¹H NMR Spectrum
5:51
No. of Signals, Integration, Chemical Shifts, and Splitting Patterns
5:52
Number of Signals in NMR (Chemical Equivalence)
7:52
Example 1: How Many Signals in ¹H NMR?
7:53
Example 2: How Many Signals in ¹H NMR?
9:36
Example 3: How Many Signals in ¹H NMR?
12:15
Example 4: How Many Signals in ¹H NMR?
13:47
Example 5: How Many Signals in ¹H NMR?
16:12
Size of Signals in NMR (Peak Area or Integration)
21:23
Size of Signals in NMR (Peak Area or Integration)
21:24
Using Integral Trails
25:15
Example 1: C₈H₁₈O
25:16
Example 2: C₃H₈O
27:17
Example 3: C₇H₈
28:21
Location of NMR Signal (Chemical Shift)
29:05
Location of NMR Signal (Chemical Shift)
29:06
¹H NMR Chemical Shifts
33:20
¹H NMR Chemical Shifts
33:21
¹H NMR Chemical Shifts (Protons on Carbon)
37:03
¹H NMR Chemical Shifts (Protons on Carbon)
37:04
Chemical Shifts of H's on N or O
39:01
Chemical Shifts of H's on N or O
39:02
Estimating Chemical Shifts
41:13
Example 1: Estimating Chemical Shifts
41:14
Example 2: Estimating Chemical Shifts
43:22
Functional Group Effects are Additive
45:28
Calculating Chemical Shifts
47:38
Methylene Calculation
47:39
Methine Calculation
48:20
Protons on sp³ Carbons: Chemical Shift Calculation Table
48:50
Example: Estimate the Chemical Shift of the Selected H
50:29
Effects of Resonance on Chemical Shifts
53:11
Example 1: Effects of Resonance on Chemical Shifts
53:12
Example 2: Effects of Resonance on Chemical Shifts
55:09
Example 3: Effects of Resonance on Chemical Shifts
57:08
Shape of NMR Signal (Splitting Patterns)
59:17
Shape of NMR Signal (Splitting Patterns)
59:18
Understanding Splitting Patterns: The 'n+1 Rule'
1:01:24
Understanding Splitting Patterns: The 'n+1 Rule'
1:01:25
Explanation of n+1 Rule
1:02:42
Explanation of n+1 Rule: One Neighbor
1:02:43
Explanation of n+1 Rule: Two Neighbors
1:06:23
Summary of Splitting Patterns
1:06:24
Summary of Splitting Patterns
1:10:45
Predicting ¹H NMR Spectra
1:10:46
Example 1: Predicting ¹H NMR Spectra
1:13:30
Example 2: Predicting ¹H NMR Spectra
1:19:07
Example 3: Predicting ¹H NMR Spectra
1:23:50
Example 4: Predicting ¹H NMR Spectra
1:29:27
Nuclear Magnetic Resonance (NMR) Spectroscopy, Part II

2h 3m 48s

Intro
0:00
¹H NMR Problem-Solving Strategies
0:18
Step 1: Analyze IR Spectrum (If Provided)
0:19
Step 2: Analyze Molecular Formula (If Provided)
2:06
Step 3: Draw Pieces of Molecule
3:49
Step 4: Confirm Pieces
6:30
Step 5: Put the Pieces Together!
7:23
Step 6: Check Your Answer!
8:21
Examples
9:17
Example 1: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data
9:18
Example 2: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data
17:27
¹H NMR Practice
20:57
¹H NMR Practice 1: C₁₀H₁₄
20:58
¹H NMR Practice 2: C₄H₈O₂
29:50
¹H NMR Practice 3: C₆H₁₂O₃
39:19
¹H NMR Practice 4: C₈H₁₈
50:19
More About Coupling Constants (J Values)
57:11
Vicinal (3-bond) and Geminal (2-bond)
57:12
Cyclohexane (ax-ax) and Cyclohexane (ax-eq) or (eq-eq)
59:50
Geminal (Alkene), Cis (Alkene), and Trans (Alkene)
1:02:40
Allylic (4-bond) and W-coupling (4-bond) (Rigid Structures Only)
1:04:05
¹H NMR Advanced Splitting Patterns
1:05:39
Example 1: ¹H NMR Advanced Splitting Patterns
1:05:40
Example 2: ¹H NMR Advanced Splitting Patterns
1:10:01
Example 3: ¹H NMR Advanced Splitting Patterns
1:13:45
¹H NMR Practice
1:22:53
¹H NMR Practice 5: C₁₁H₁₇N
1:22:54
¹H NMR Practice 6: C₉H₁₀O
1:34:04
¹³C NMR Spectroscopy
1:44:49
¹³C NMR Spectroscopy
1:44:50
¹³C NMR Chemical Shifts
1:47:24
¹³C NMR Chemical Shifts Part 1
1:47:25
¹³C NMR Chemical Shifts Part 2
1:48:59
¹³C NMR Practice
1:50:16
¹³C NMR Practice 1
1:50:17
¹³C NMR Practice 2
1:58:30
C-13 DEPT NMR Experiments

23m 10s

Intro
0:00
C-13 DEPT NMR Spectoscopy
0:13
Overview
0:14
C-13 DEPT NMR Spectoscopy, Cont.
3:31
Match C-13 Peaks to Carbons on Structure
3:32
C-13 DEPT NMR Spectoscopy, Cont.
8:46
Predict the DEPT-90 and DEPT-135 Spectra for the Given Compound
8:47
C-13 DEPT NMR Spectoscopy, Cont.
12:30
Predict the DEPT-90 and DEPT-135 Spectra for the Given Compound
12:31
C-13 DEPT NMR Spectoscopy, Cont.
17:19
Determine the Structure of an Unknown Compound using IR Spectrum and C-13 DEPT NMR
17:20
Two-Dimensional NMR Techniques: COSY

33m 39s

Intro
0:00
Two-Dimensional NMR Techniques: COSY
0:14
How Do We Determine Which Protons are Related in the NMR?
0:15
Two-Dimensional NMR Techniques: COSY
1:48
COSY Spectra
1:49
Two-Dimensional NMR Techniques: COSY
7:00
COSY Correlation
7:01
Two-Dimensional NMR Techniques: COSY
8:55
Complete the COSY NMR Spectrum for the Given Compoun
8:56
NMR Practice Problem
15:40
Provide a Structure for the Unknown Compound with the H NMR and COSY Spectra Shown
15:41
Two-Dimensional NMR Techniques: HETCOR & HMBC

15m 5s

Intro
0:00
HETCOR
0:15
Heteronuclear Correlation Spectroscopy
0:16
HETCOR
2:04
HETCOR Example
2:05
HMBC
11:07
Heteronuclear Multiple Bond Correlation
11:08
HMBC
13:14
HMB Example
13:15
Mass Spectrometry

1h 28m 35s

Intro
0:00
Introduction to Mass Spectrometry
0:37
Uses of Mass Spectrometry: Molecular Mass
0:38
Uses of Mass Spectrometry: Molecular Formula
1:04
Uses of Mass Spectrometry: Structural Information
1:21
Uses of Mass Spectrometry: In Conjunction with Gas Chromatography
2:03
Obtaining a Mass Spectrum
2:59
Obtaining a Mass Spectrum
3:00
The Components of a Mass Spectrum
6:44
The Components of a Mass Spectrum
6:45
What is the Mass of a Single Molecule
12:13
Example: CH₄
12:14
Example: ¹³CH₄
12:51
What Ratio is Expected for the Molecular Ion Peaks of C₂H₆?
14:20
Other Isotopes of High Abundance
16:30
Example: Cl Atoms
16:31
Example: Br Atoms
18:33
Mass Spectrometry of Chloroethane
19:22
Mass Spectrometry of Bromobutane
21:23
Isotopic Abundance can be Calculated
22:48
What Ratios are Expected for the Molecular Ion Peaks of CH₂Br₂?
22:49
Determining Molecular Formula from High-resolution Mass Spectrometry
26:53
Exact Masses of Various Elements
26:54
Fragmentation of various Functional Groups
28:42
What is More Stable, a Carbocation C⁺ or a Radical R?
28:43
Fragmentation is More Likely If It Gives Relatively Stable Carbocations and Radicals
31:37
Mass Spectra of Alkanes
33:15
Example: Hexane
33:16
Fragmentation Method 1
34:19
Fragmentation Method 2
35:46
Fragmentation Method 3
36:15
Mass of Common Fragments
37:07
Mass of Common Fragments
37:08
Mass Spectra of Alkanes
39:28
Mass Spectra of Alkanes
39:29
What are the Peaks at m/z 15 and 71 So Small?
41:01
Branched Alkanes
43:12
Explain Why the Base Peak of 2-methylhexane is at m/z 43 (M-57)
43:13
Mass Spectra of Alkenes
45:42
Mass Spectra of Alkenes: Remove 1 e⁻
45:43
Mass Spectra of Alkenes: Fragment
46:14
High-Energy Pi Electron is Most Likely Removed
47:59
Mass Spectra of Aromatic Compounds
49:01
Mass Spectra of Aromatic Compounds
49:02
Mass Spectra of Alcohols
51:32
Mass Spectra of Alcohols
51:33
Mass Spectra of Ethers
54:53
Mass Spectra of Ethers
54:54
Mass Spectra of Amines
56:49
Mass Spectra of Amines
56:50
Mass Spectra of Aldehydes & Ketones
59:23
Mass Spectra of Aldehydes & Ketones
59:24
McLafferty Rearrangement
1:01:29
McLafferty Rearrangement
1:01:30
Mass Spectra of Esters
1:04:15
Mass Spectra of Esters
1:01:16
Mass Spectrometry Discussion I
1:05:01
For the Given Molecule (M=58), Do You Expect the More Abundant Peak to Be m/z 15 or m/z 43?
1:05:02
Mass Spectrometry Discussion II
1:08:13
For the Given Molecule (M=74), Do You Expect the More Abundant Peak to Be m/z 31, m/z 45, or m/z 59?
1:08:14
Mass Spectrometry Discussion III
1:11:42
Explain Why the Mass Spectra of Methyl Ketones Typically have a Peak at m/z 43
1:11:43
Mass Spectrometry Discussion IV
1:14:46
In the Mass Spectrum of the Given Molecule (M=88), Account for the Peaks at m/z 45 and m/z 57
1:14:47
Mass Spectrometry Discussion V
1:18:25
How Could You Use Mass Spectrometry to Distinguish Between the Following Two Compounds (M=73)?
1:18:26
Mass Spectrometry Discussion VI
1:22:45
What Would be the m/z Ratio for the Fragment for the Fragment Resulting from a McLafferty Rearrangement for the Following Molecule (M=114)?
1:22:46
Section 14: Organic Chemistry Lab
Completing the Reagent Table for Prelab

21m 9s

Intro
0:00
Sample Reagent Table
0:11
Reagent Table Overview
0:12
Calculate Moles of 2-bromoaniline
6:44
Calculate Molar Amounts of Each Reagent
9:20
Calculate Mole of NaNO₂
9:21
Calculate Moles of KI
10:33
Identify the Limiting Reagent
11:17
Which Reagent is the Limiting Reagent?
11:18
Calculate Molar Equivalents
13:37
Molar Equivalents
13:38
Calculate Theoretical Yield
16:40
Theoretical Yield
16:41
Calculate Actual Yield (%Yield)
18:30
Actual Yield (%Yield)
18:31
Introduction to Melting Points

16m 10s

Intro
0:00
Definition of a Melting Point (mp)
0:04
Definition of a Melting Point (mp)
0:05
Solid Samples Melt Gradually
1:49
Recording Range of Melting Temperature
2:04
Melting Point Theory
3:14
Melting Point Theory
3:15
Effects of Impurities on a Melting Point
3:57
Effects of Impurities on a Melting Point
3:58
Special Exception: Eutectic Mixtures
5:09
Freezing Point Depression by Solutes
5:39
Melting Point Uses
6:19
Solid Compound
6:20
Determine Purity of a Sample
6:42
Identify an Unknown Solid
7:06
Recording a Melting Point
9:03
Pack 1-3 mm of Dry Powder in MP Tube
9:04
Slowly Heat Sample
9:55
Record Temperature at First Sign of Melting
10:33
Record Temperature When Last Crystal Disappears
11:26
Discard MP Tube in Glass Waste
11:32
Determine Approximate MP
11:42
Tips, Tricks and Warnings
12:28
Use Small, Tightly Packed Sample
12:29
Be Sure MP Apparatus is Cool
12:45
Never Reuse a MP Tube
13:16
Sample May Decompose
13:30
If Pure Melting Point (MP) Doesn't Match Literature
14:20
Melting Point Lab

8m 17s

Intro
0:00
Melting Point Tubes
0:40
Melting Point Apparatus
3:42
Recording a melting Point
5:50
Introduction to Recrystallization

22m

Intro
0:00
Crystallization to Purify a Solid
0:10
Crude Solid
0:11
Hot Solution
0:20
Crystals
1:09
Supernatant Liquid
1:20
Theory of Crystallization
2:34
Theory of Crystallization
2:35
Analysis and Obtaining a Second Crop
3:40
Crystals → Melting Point, TLC
3:41
Supernatant Liquid → Crude Solid → Pure Solid
4:18
Crystallize Again → Pure Solid (2nd Crop)
4:32
Choosing a Solvent
5:19
1. Product is Very Soluble at High Temperatures
5:20
2. Product has Low Solubility at Low Temperatures
6:00
3. Impurities are Soluble at All Temperatures
6:16
Check Handbooks for Suitable Solvents
7:33
Why Isn't This Dissolving?!
8:46
If Solid Remains When Solution is Hot
8:47
Still Not Dissolved in Hot Solvent?
10:18
Where Are My Crystals?!
12:23
If No Crystals Form When Solution is Cooled
12:24
Still No Crystals?
14:59
Tips, Tricks and Warnings
16:26
Always Use a Boiling Chip or Stick!
16:27
Use Charcoal to Remove Colored Impurities
16:52
Solvent Pairs May Be Used
18:23
Product May 'Oil Out'
20:11
Recrystallization Lab

19m 7s

Intro
0:00
Step 1: Dissolving the Solute in the Solvent
0:12
Hot Filtration
6:33
Step 2: Cooling the Solution
8:01
Step 3: Filtering the Crystals
12:08
Step 4: Removing & Drying the Crystals
16:10
Introduction to Distillation

25m 54s

Intro
0:00
Distillation: Purify a Liquid
0:04
Simple Distillation
0:05
Fractional Distillation
0:55
Theory of Distillation
1:04
Theory of Distillation
1:05
Vapor Pressure and Volatility
1:52
Vapor Pressure
1:53
Volatile Liquid
2:28
Less Volatile Liquid
3:09
Vapor Pressure vs. Boiling Point
4:03
Vapor Pressure vs. Boiling Point
4:04
Increasing Vapor Pressure
4:38
The Purpose of Boiling Chips
6:46
The Purpose of Boiling Chips
6:47
Homogeneous Mixtures of Liquids
9:24
Dalton's Law
9:25
Raoult's Law
10:27
Distilling a Mixture of Two Liquids
11:41
Distilling a Mixture of Two Liquids
11:42
Simple Distillation: Changing Vapor Composition
12:06
Vapor & Liquid
12:07
Simple Distillation: Changing Vapor Composition
14:47
Azeotrope
18:41
Fractional Distillation: Constant Vapor Composition
19:42
Fractional Distillation: Constant Vapor Composition
19:43
Distillation Lab

24m 13s

Intro
0:00
Glassware Overview
0:04
Heating a Sample
3:09
Bunsen Burner
3:10
Heating Mantle 1
4:45
Heating Mantle 2
6:18
Hot Plate
7:10
Simple Distillation Lab
8:37
Fractional Distillation Lab
17:13
Removing the Distillation Set-Up
22:41
Introduction to TLC (Thin-Layer Chromatography)

28m 51s

Intro
0:00
Chromatography
0:06
Purification & Analysis
0:07
Types of Chromatography: Thin-layer, Column, Gas, & High Performance Liquid
0:24
Theory of Chromatography
0:44
Theory of Chromatography
0:45
Performing a Thin-layer Chromatography (TLC) Analysis
2:30
Overview: Thin-layer Chromatography (TLC) Analysis
2:31
Step 1: 'Spot' the TLC Plate
4:11
Step 2: Prepare the Developing Chamber
5:54
Step 3: Develop the TLC Plate
7:30
Step 4: Visualize the Spots
9:02
Step 5: Calculate the Rf for Each Spot
12:00
Compound Polarity: Effect on Rf
16:50
Compound Polarity: Effect on Rf
16:51
Solvent Polarity: Effect on Rf
18:47
Solvent Polarity: Effect on Rf
18:48
Example: EtOAc & Hexane
19:35
Other Types of Chromatography
22:27
Thin-layer Chromatography (TLC)
22:28
Column Chromatography
22:56
High Performance Liquid (HPLC)
23:59
Gas Chromatography (GC)
24:38
Preparative 'prep' Scale Possible
28:05
TLC Analysis Lab

20m 50s

Intro
0:00
Step 1: 'Spot' the TLC Plate
0:06
Step 2: Prepare the Developing Chamber
4:06
Step 3: Develop the TLC Plate
6:26
Step 4: Visualize the Spots
7:45
Step 5: Calculate the Rf for Each Spot
11:48
How to Make Spotters
12:58
TLC Plate
16:04
Flash Column Chromatography
17:11
Introduction to Extractions

34m 25s

Intro
0:00
Extraction Purify, Separate Mixtures
0:07
Adding a Second Solvent
0:28
Mixing Two Layers
0:38
Layers Settle
0:54
Separate Layers
1:05
Extraction Uses
1:20
To Separate Based on Difference in Solubility/Polarity
1:21
To Separate Based on Differences in Reactivity
2:11
Separate & Isolate
2:20
Theory of Extraction
3:03
Aqueous & Organic Phases
3:04
Solubility: 'Like Dissolves Like'
3:25
Separation of Layers
4:06
Partitioning
4:14
Distribution Coefficient, K
5:03
Solutes Partition Between Phases
5:04
Distribution Coefficient, K at Equilibrium
6:27
Acid-Base Extractions
8:09
Organic Layer
8:10
Adding Aqueous HCl & Mixing Two Layers
8:46
Neutralize (Adding Aqueous NaOH)
10:05
Adding Organic Solvent Mix Two Layers 'Back Extract'
10:24
Final Results
10:43
Planning an Acid-Base Extraction, Part 1
11:01
Solute Type: Neutral
11:02
Aqueous Solution: Water
13:40
Solute Type: Basic
14:43
Solute Type: Weakly Acidic
15:23
Solute Type: Acidic
16:12
Planning an Acid-Base Extraction, Part 2
17:34
Planning an Acid-Base Extraction
17:35
Performing an Extraction
19:34
Pour Solution into Sep Funnel
19:35
Add Second Liquid
20:07
Add Stopper, Cover with Hand, Remove from Ring
20:48
Tip Upside Down, Open Stopcock to Vent Pressure
21:00
Shake to Mix Two Layers
21:30
Remove Stopper & Drain Bottom Layer
21:40
Reaction Work-up: Purify, Isolate Product
22:03
Typical Reaction is Run in Organic Solvent
22:04
Starting a Reaction Work-up
22:33
Extracting the Product with Organic Solvent
23:17
Combined Extracts are Washed
23:40
Organic Layer is 'Dried'
24:23
Finding the Product
26:38
Which Layer is Which?
26:39
Where is My Product?
28:00
Tips, Tricks and Warnings
29:29
Leaking Sep Funnel
29:30
Caution When Mixing Layers & Using Ether
30:17
If an Emulsion Forms
31:51
Extraction Lab

14m 49s

Intro
0:00
Step 1: Preparing the Separatory Funnel
0:03
Step 2: Adding Sample
1:18
Step 3: Mixing the Two Layers
2:59
Step 4: Draining the Bottom Layers
4:59
Step 5: Performing a Second Extraction
5:50
Step 6: Drying the Organic Layer
7:21
Step 7: Gravity Filtration
9:35
Possible Extraction Challenges
12:55
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Lecture Comments (27)

1 answer

Last reply by: Professor Starkey
Sun Mar 25, 2018 4:55 PM

Post by Wendi Li on March 25, 2018

Hi Professor Starkey. At 54:45 for the second prediction example, how did you get the final product reacted with H2SO4? I understand the H+ will take OH- off and form H2O, but how can you form a pi bond?

Thanks!

1 answer

Last reply by: Professor Starkey
Mon Oct 20, 2014 11:45 PM

Post by Ahmad Alshammari on October 20, 2014

Let me tell you something Pro Starkey. I studied your lectures before the exam in hours. And I ended up with B+ in the exam. I wish I studied it in weeks before the exam, I am sure I would've got a hundred%!

Thank you very much!

1 answer

Last reply by: Professor Starkey
Tue Mar 18, 2014 9:37 PM

Post by saima khwaja on March 18, 2014

Why is MgBr and not MgCl? and is that one molecule or two separate?

2 answers

Last reply by: Nicholas Elias
Fri Oct 18, 2013 4:46 PM

Post by Nicholas Elias on October 18, 2013

Does branching also influence the boiling point of an alcohol like lets say we compare a 5 carbon branched alcohol to pentanol?

3 answers

Last reply by: Professor Starkey
Sun Oct 13, 2013 11:18 PM

Post by Serena Chanelian on October 9, 2013

Hi! The workup after the ketone/aldehyde is exposed to a Grignard Reagent is H20 or H30+ to protonate the alkoxide and generate an alcohol. Would using methanol CH3OH as the workup work as well since the pH of water and methanol are very similar? Thank you!

1 answer

Last reply by: Professor Starkey
Tue Aug 13, 2013 11:32 AM

Post by Briana Kallias on August 11, 2013

In the last slide where we have to provide the reagents for the first problem, would it be possible to, step 1: react it with NaBH4 in Ch3OH to create the OH group, step 2: react with OH- to remove one hydrogen and create a primary carbocation, and step 3: react with LiCH3 to add the new CH3 group to where the carbocation was located?

1 answer

Last reply by: Professor Starkey
Sun Sep 23, 2012 11:05 PM

Post by Nigel Hessing on September 22, 2012

Hello, at 24:50 you said that allylic and benzylic reactions favours SN2, but I thought that they favoured SN1 because they form a stable carbocation.. I thought because the Sn2 is a concerted mechanism the transition state is not as important as the carbocation? Can you please clarify?

1 answer

Last reply by: Professor Starkey
Fri Apr 27, 2012 1:01 AM

Post by Rachel Paquette on April 26, 2012

at 42:00 min in you are talking about proton transfer form the H-OCH2CH3 to the cyclopentane, however, every time I try this problem on my own I want to reaction the entire ethanol group and then deprotonate the H. Does this not occur because the ethanol is not needed as a nucleophile but instead the cylopentane is acting as the nucleophile and just needs an electrophile?

1 answer

Last reply by: Professor Starkey
Tue Dec 13, 2011 8:35 PM

Post by Matt Minken on December 11, 2011

For the last slide in the transform problem, could you have used the organolithium CH3Li? thanks

2 answers

Last reply by: Professor Starkey
Sat Nov 5, 2011 4:35 PM

Post by Thomas Notto on October 27, 2011

In the above lecture you wrote "-OCH3MgBr".... Shouldn't that be -OCH3MgCl... since you started with MgCl... Just wondering where the "Br" came from in the explained reaction.

0 answers

Post by christopher aime on April 30, 2011

agreed

1 answer

Last reply by: Professor Starkey
Sat Jul 30, 2011 12:20 AM

Post by Dalila Talbi on April 19, 2011

Good morning,
I like Professor Starkey's videos. Is there a way I can have a print out of her notes shown on the video? it will help me a lot.
Thanks
D

Alcohols, Part I

Draw the product formed from this reaction:
Draw the product formed from this reaction:
Draw the product formed from this reaction:
Draw the product formed from this reaction:
Draw the products formed for the first and second reaction:
Draw the product formed from this reaction:

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.

Answer

Alcohols, Part I

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

  • Intro 0:00
  • Alcohols 0:11
    • Attributes of Alcohols
    • Boiling Points
  • Water Solubility 5:00
    • Water Solubility (Like Dissolves Like)
  • Acidity of Alcohols 9:39
    • Comparison of Alcohols Acidity
  • Preparation of Alkoxides 13:03
    • Using Strong Base Like Sodium Hydride
    • Using Redox Reaction
  • Preparation of Alkoxides 17:41
    • Using K°
    • Phenols Are More Acidic Than Other Alcohols
  • Synthesis of Alcohols, ROH 21:43
    • Synthesis of Alcohols from Alkyl Halides, RX (SN2 or SN1)
  • Synthesis of Alcohols, ROH 25:08
    • Unlikely on 2° RX (E2 Favored)
    • Impossible on 3° RX (E2) and Phenyl/Vinyl RX (N/R)
  • Synthesis of Alcohols, ROH 26:26
    • SN1 with H₂O 'Solvolysis' or 'Hydrolysis'
    • Carbocation Can Rearrange
  • Synthesis of Alcohols, ROH 30:08
    • Synthesis of Alcohols From Alkenes: Hydration
    • Synthesis of Alcohols From Alkenes: Oxidation/Diol
  • Synthesis of Alcohols, ROH 33:14
    • Synthesis of Alcohols From Ketones and Aldehydes
  • Organometallic Reagents: Preparation 37:03
    • Grignard (RMgX)
    • Organolithium (Rli)
  • Organometallic Reagents: Reactions 41:45
    • Reactions of Organometallic Reagents
  • Organometallic Reagents: Reactions as Strong Nu: 46:40
    • Example 1: Reactions as Strong Nu:
    • Example 2: Reactions as Strong Nu:
  • Hydride Nu: 50:52
    • Hydride Nu:
  • Examples 53:34
    • Predict 1
    • Predict 2
  • Examples 56:43
    • Transform
    • Provide Starting Material

Transcription: Alcohols, Part I

Hi and welcome back to Educator.0000

Next we are going to be talking about alcohols; we are going to do two different parts.0002

The first part is going to be discussing the structure of alcohols and the synthesis of alcohols; in other words, how do you prepare them.0006

An alcohol is an organic molecule that contains an OH functional group.0013

Because oxygen is so electronegative, it pulls a lot of electron density toward itself, especially away from this tiny little hydrogen.0018

What we end up with is a huge partial minus and partial plus on these two atoms; so the OH group is a very, very polar functional group.0025

That is going to define a lot of its physical properties; they can undergo hydrogen bonding with each other.0034

In other words, one molecule of an alcohol, partial minus, partial plus, can interact with another molecule of alcohol, partial minus, partial plus.0041

There is such a strong attraction between the oxygen on one and the hydrogen on the other that we actually draw a dashed line connecting them.0056

We call that a hydrogen bond; it is easy for the protons to be transferred from one structure to the other.0064

It results in a very strong association, a very strong association, a very strong affinity for one molecule of an alcohol to another molecule of an alcohol.0073

The physical property effects we see on that is we see an increased boiling point.0080

Because if these are very strongly attracted to one another, it is going to difficult to tear them apart from one another and put them in the vapor phase.0084

We also see an increased water solubility because very much like water, like dissolves like; water is polar; water can hydrogen bond; so a very strong affinity between alcohols and water.0091

Another feature that we are going to be seeing is that the OH group is acidic; in other words, it can be deprotonated.0102

It can act as an acid; it can donate an H+ very easily; we will see reactions of alcohol with a wide variety of bases as well.0111

Let's take a look at some sample boiling points; these boiling points are listed in degrees C so that we can observe the effects on boiling point by various functional groups.0122

If we take a look at a molecule like pentane, completely nonpolar molecule; all it has are carbon-carbon bonds and carbon-hydrogen bonds; all very nonpolar.0137

We compare that to an ether, let's say, where we have an oxygen in here; which now makes it--we have some polar bonds; so there is a small dipole moment here; this is polar molecule.0149

But you don't see a huge difference in boiling points; these are about the same molecular weight; not a huge difference, they are essentially the same.0165

The polarity isn't having... this small amount of polarity is not having a big difference in the boiling point.0174

But instead, if you have an OH group for that oxygen, rather than just an oxygen with carbons on either sides, now look at the huge jump we get in boiling point difference.0179

Even ethanol is now a smaller molecule, yet it has over twice the boiling point; this effect here is because of hydrogen bonding.0190

Those ethanol molecules are very strongly attracted to one another; it is difficult to take them apart, put them in the vapor phase; we have to put more energy into it; that increases the boiling point.0202

When we compare ethanol to butanol, how do we explain that difference in boiling points?--they both have the OH; so they have the same polarity, same hydrogen bonding capability.0213

But now we see the trend where as you increase the molecular weight, you increase the boiling point; so all other things being equal, a larger molecule is going to have a higher boiling point.0225

Then finally I put this molecule on here; this is called ethylene glycol; he is an example of a diol with two OH groups.0235

In fact, I just noticed a typo with my structure here, excuse me; ethylene glycol has just two carbons and two OHs.0242

Notice this boiling point--197; so lots of hydrogen bonding in the case of ethylene glycol because it has two OH groups; a very big network of hydrogen bonding there.0251

That high boiling point is very useful to us; we use ethylene glycol as a component of antifreeze; it is good in that capacity because it is very hard to boil.0267

Antifreeze is th coolant that goes through your car and cools down the engine; it needs to be high boiling because it is going to get very hot.0279

We don't want it to just boil away; you can't just fill your radiator with water because the boiling point is too low.0285

We can see here a clear trend that the presence of an OH group or multiple OH groups is going to have an increase in the boiling point of those molecules.0290

When we take a look at water solubility, we describe water solubility in terms of grams per 100 milliliters of water.0302

If I had a 100mL sample of water, how much of this material could I dissolve in there?0313

If we take again a look at something like pentane, this liquid is completely immiscible with water; they form two separate layers; there is no solubility.0318

Once again, it is because this is a completely nonpolar molecule; it has no affinity for water; in fact, you can describe this as being hydrophobic.0327

Something that is nonpolar is hydrophobic--it fears water; there is nothing about it that is similar to water.0339

Remember, with solubility, we are always talking about like dissolves like; the more similar a molecule is to water, the more it has in common with it, the better the solubility.0345

For example, if you put in an ether, now you have a little bit of polarity; we have a big jump in water solubility.0360

This does have appreciable water solubility; that is because it can accept hydrogen bonds from water.0369

In other words, this oxygen can be attracted to a water molecule and form some hydrogen bonding there; it can be a hydrogen bond acceptor from water.0382

Even though this ether can't hydrogen bond with itself, if you just had a sample of ether, it can undergo hydrogen bonding with water; that increases its water solubility.0392

This is diethyl ether; because it has some water solubility, that is why whenever we use ether in a reaction work up and we are doing an extractive work up.0403

The ether layer is wet with dissolved water and it must be dried.0414

Any extractive work up that you do, where you partition your reaction components between an organic layer and an aqueous layer in a sep funnel for example.0427

If you are using ether, some water will always dissolve into the ether layer and the ether going into the water layer.0437

Part of any work up procedure is going to be taking that ether layer and drying it somehow.0446

Removing that water by using a drying agent like calcium chloride or magnesium sulfate and getting rid of that water.0450

By looking at the structure, we can see the polarity and the hydrogen bonding capability; that would explain why it does have some water solubility.0457

It is also going to be something that is very relevant to us in the laboratory.0466

But then when we move to a molecule with an OH, you might think now there must be a huge jump in water solubility because now we can now both donate and accept hydrogen bonding, a lot more interaction.0470

But when we look at these two molecules, they both have four carbons; but this has a really long carbon chain that is nonpolar.0480

We end up getting this balance, this tradeoff, between this nonpolar part and this polar part, this hydrophilic part and this hydrophobic part.0488

You can see that actually these have very similar water solubilities, not very different at all.0496

However, if you shorten up that nonpolar chain and you look at something like this--this is ethanol; it is completely miscible with water.0502

Now it is a polar enough water molecule; it has this hydrogen bonding capability; it is soluble in all proportions.0513

You can never have too much ethanol so that it separates out as a separate layer from water.0521

This is the alcohol; we are studying alcohols in this unit; we have heard of alcohols before in our day to day lives.0527

One of the alcohols is one that humans can drink without getting too sick; that is grain alcohol; this is the actual alcohol structure.0534

As an organic chemist, our definition of alcohols extend to anything containing an OH group.0544

But in our everyday lives, this is the alcohol that is referred to as alcohol that is drinkable; it is the two carbon chain called ethanol.0550

Of course, the alcoholic beverages that are out there are aqueous solutions with some alcohol in there; the proof tells you what percentage of alcohol is in there; the rest of it is just water.0560

This is something that we might already have seen some evidence for; that ethanol is in fact miscible with water.0572

Let's talk about the other physical property, the other reactivity or feature of an alcohol; that is the fact that it is acidic; it can be deprotonated.0582

We have... let's compare an alcohol OH to an amine NH and see if maybe we can explain why an OH is pretty acidic.0591

If fact, if you look at their pKa numbers, this has a pKa of about 16; that is a very low number, really easy to deprotonate an alcohol; where an amine has a pKa of about 40.0599

Let's just do this comparison as a review of things that affect acidity and basicity and see if we can explain that and understand why alcohols are so easily deprotonated.0610

As usual, we are going to want to consider the conjugate base of each of these to decide why they have such a big difference in pKa.0621

In other words, let's let methanol be an acid and get deprotonated; instead of having an OH, we will have an O-; that is the conjugate base of methanol.0629

The conjugate base of methyl amine has an NH with a minus; we remove an H+ from each; now we compare the two; we have an O- versus an N-.0643

Which of those is more stable?--we look for a difference in the stability of the conjugate bases to explain differences in acidity.0658

We know that oxygen is more electronegative than nitrogen; let's start by stating our facts; oxygen is more electronegative than nitrogen.0666

If you have a negative charge, would that prefer to be on the more electronegative atom or the less electronegative atom?0682

It prefers on the more electronegative; oxygen better handles the negative charge because it is more electronegative and O- is better than N-.0688

That means CH3O- is the more stable and therefore less reactive; if you are more stable, you are less reactive and therefore weaker conjugate base.0703

Whichever conjugate base is more stable, that makes it less reactive; that makes it the weaker conjugate base; and the weaker conjugate base has the stronger parent acid.0721

That can be our last comment; CH3O- has the stronger parent acid; is that what our pKa data tells us?0730

Sure, again pKa of 16; that is a difference of twenty-four units; that is kajillions times more acidic having a hydrogen on an oxygen compared to a hydrogen on something like a nitrogen.0741

It is because oxygen is so electronegative; if you think about the periodic table, we all know that fluorine is the most electronegative atom.0753

Oxygen right next door is the second most electronegative atom in the periodic table.0761

Oxygen, that means it is really good at pulling electron density toward itself; it is very, very happy having a negative charge on itself.0767

That means it is pretty reasonable to deprotonate an OH and convert it to an O- because oxygen doesn't mind having a negative charge.0775

If we wanted to deprotonate an OH to give an RO---these are called alkoxides because we have an alkyl group and an O-.0785

Just like hydroxide is HO-, alkoxide is RO-; how would we prepare an alkoxide if we wanted to?0797

What we would have to do is we would start with the alcohol and we would completely deprotonate it; we want to remove 100% of the H+ from all the OH containing molecules.0804

There is going to be two strategies we can have for this; one option is we can use a very strong base like sodium hydride.0816

Again when I say strong base, what do you think as sometimes a strong base?--you think hydroxide, NaOH; NaOH is not going to do it.0822

Think about it; you can't use an O- to create another O- and be able to do so in an equilibrium that is going to be heavily favored in one direction or the other.0830

This would simply set up an equilibrium with water and the alkoxide; we don't want an equilibrium; we want a one way street.0841

Rather than using NaOH, the base we are going to be using is sodium hydride; that is NaH; that is Na+ and H-; H- is called hydride.0850

This is a very effective base; we just said the alcohol can act as an acid; what happens when you react these two?0863

The base is going to grab that proton, leave the two electrons behind on the oxygen; it is going to give us an O-; it is going to form methoxide here.0871

If we use sodium hydride, we are going to get the sodium salt; this forms sodium methoxide; just a little vocabulary in there on how we are going to name our alkoxides if we have them.0883

What is the other product in this case?--we use sodium hydride as a base; we have an H-; it is combining with an H+.0896

Our other product is hydrogen; what do you know about hydrogen?--it is a gas; it is going to bubble away.0903

Tell me how does this reverse reaction look?--if you wanted to consider whether or not it is going to be going forwards or backwards.0910

Because our hydrogen gas, one of our products, is leaving, the reverse reaction becomes impossible; there is no reverse reaction.0918

That is what makes sodium hydride something that is ideal for making alkoxide; 100% of the alcohol will be converted to an alkoxide.0926

Another possibility is to use a redox reaction to do this, pretty much the same transformation.0938

But instead of using sodium hydride, we are going to use sodium metal; this is sodium zero (Na0) or sodium dot(Na·).0944

This is a metal; it has a single electron in its valence shell that makes it a very good reducing agent.0950

We have seen sodium metal as a reducing agent for alkynes, doing the dissolving metal reduction to a trans alkene.0956

If we were to react with an alcohol instead, what happens is we end up forming two equivalents of sodium methoxide and hydrogen gas.0963

We actually get the exact same products out that we did in this acid-base reaction; but this mechanism is more complicated.0974

It is not a simple proton transfer; it is an electron transfer; we call those redox reactions.0980

We look at this reaction carefully; we see that we are starting with sodium metal and we end up with Na+; that is the oxidation that is occurring.0986

In other words, sodium is releasing that electron, donating it to someone else, getting oxidized itself and causing a reduction in the hydrogen of the methanol.0994

That started out with a +1 oxidation state; but when it is in its elemental form, it is hydrogen gas; it has a 0 oxidation state... 0 oxidation number.1005

We went from a +1 to a 0; that is a reduction; in oxidation... where there is reduction, the gain electrons.1018

This mechanism is not one we are going to study; but it is more of a predict-the-product or providing the reagents.1025

The other thing, like all redox reactions, this reversible reaction is impossible; redox reactions always go to transferring the electron to give the more stable species.1033

What is great about both of these is that they are both irreversible; if we need to form an alkoxide, you have two good choices, sodium hydride or sodium metal.1045

Those are two great reagents that we can count on; sodium metal works; but sodium, lithium, potassium, those are all group 1A; those would all work to do this oxidation.1058

As you move down in the periodic table, your atoms are getting bigger and bigger and bigger; that electron is being held even further and further from the nucleus.1073

That makes it a lot more reactive; so something like potassium, which is bigger, is going to be more reactive.1081

That is useful for certain alcohols like this t-butyl alcohol; this is a weaker acid than something like ethanol or methanol; why is that?1087

Because these alkyl groups, this tertiary alcohol, this is a tertiary alcohol; those are in general weaker acids and less willing to give up a proton than a primary or secondary.1104

Because these alkyl groups are all electron donating; that is not a good thing if you want to be forming and O- here; that would be destabilized by those alkyl groups donating electron density.1117

This would be a very very very slow reaction if we use sodium metal or even lithium metal; but if you use potassium metal, that is going to be strong enough to do this redox reaction.1128

Same idea, our products are going to be an O-K+; we are going to get the alkoxide; the other product here is this H+ that we have--is going to come off as hydrogen gas.1141

When we balance our redox reaction, you see we are using two equivalents of the alcohol and two equivalents of the potassium; so we will get two equivalents of this guy.1158

This is called potassium t-butoxide... t-butoxide or tBuOK; we have seen this before as a nice strong bulky base that we have used.1165

The reason that we usually see this as the potassium salt is because that is the one that is commercially available; that is the one that is typically made.1179

That is how we typically make it--is by using potassium metal to do this redox reaction.1186

One other example of an alcohol, when we are talking about acidity, let's talk a second about phenols; a phenol is a very special alcohol; it is when we have the OH group on a benzene ring.1193

These are significantly more acidic than other alcohols; an ordinary alcohol has a pKa of something like 16 or 18 or somewhere in that range; phenol has a pKa of about 10.1203

Again eight zeros; that is tens of millions of times more acidic; in that case, this NaOH is okay; this is a weaker base--is okay.1214

You don't need to use sodium hydride; you don't need to use sodium metal; you can but you don't have to.1230

Typically we try and use the least reactive base we can because that is going to be easier to handle and maybe cheaper or a simpler reaction to run; so weaker base is okay.1236

When we do the deprotonation here, now we are using hydroxide to do our deprotonation; the products then are going to be sodium phenoxide--is what we call it when we have a pheynl O-.1253

Sodium phenoxide and water as our other product; water has a pKa of about 16 which would not be good if we were trying to deprotonate something with a very similar pKa.1265

But because this is so much more acidic, it is a million times more acidic, we know the equilibrium lies in the direction of the weaker acid-base pair.1275

In this case, the equilibrium would be very much favored in the forward direction.1285

In fact hydroxide is very effective and is suitable for deprotonating a phenoxide and essentially completely converting it to the anion, to the O-, the alkoxide.1290

How would we make an alcohol group?--where does an OH come from in a structure?--there is a few different strategies we can have for this.1306

One way of installing that OH group is by doing some kind substitution reaction.1314

In other words, if I had a leaving group on the carbon chain, I could replace that leaving group with an OH; then my resulting product would be an alcohol.1319

We have a few different substitution mechanisms; we have Sn1 mechanism; we have Sn2 mechanism; let's take a look at both of those.1327

If we wanted to do an Sn2, remember Sn2 is backside attack; we need a strong nucleophile to come in and attack and kick off the leaving group in a single step.1335

The nucleophile I would use here would be hydroxide, very strong nucleophile; it is great at doing the Sn2; the problem is that it is also a very strong base.1344

We have a competition going on between the Sn2 that it would do if it was a nucleophile or an E2 is another thing it could do as a base--it could go after a proton.1358

The way we decided between Sn2 and E2, this competition, is we considered steric hindrance knowing that the backside attack can't have any steric hindrance.1371

When would the Sn2 mechanism be reasonable for alcohol synthesis?--only when our carbon chain has very little if any steric hindrance.1381

If we have a methyl halide or if we have a primary halide, those would be best; maybe it is allylic or benzylic; that would also help support the Sn2 mechanism.1392

For example, if you had ethyl bromide and you treat him with sodium hydroxide, because this is a primary RX, a primary alkyl halide, this is our electrophile.1403

The hydroxide is our nucleophile; no problem attacking the carbon, kicking off the leaving group; this would be a great Sn2.1416

This would be a great Sn2; this would be a reasonable way to make an alcohol; we just made an alcohol by using hydroxide as our nucleophile.1426

This one is a little trickier because we have... if you look at this carbon, it is now secondary; it has some steric hindrance.1438

But because it is allylic, this is something that makes the Sn2 not so bad; that is something that would make this possible.1445

The reason Sn2 is okay here is because the π bond stabilizes the transition state of the Sn2; we have p orbitals here.1459

We form a p orbital as the nucleophile is kicking out the leaving group; that helps make the Sn2 a faster reaction; it competes better.1473

This is another case where, even though it is secondary, you would probably get as your major product the substitution product.1483

But that is a rare case--if it is benzylic meaning it is next to a benzene ring or allylic meaning it is next to a double bond.1493

Otherwise if you are a secondary alkyl halide, you are a secondary leaving group, there is enough steric hindrance where Sn2 is not going to be favorable.1500

For example, if we just have plain old cyclopentyl bromide and we try to do hydroxide, there is enough sterics here that, instead of doing the Sn2, the E2 is faster.1510

Meaning it acts as a base; it attacks the β hydrogen--that is what bases do; forms a π bond, kicks out the leaving group.1522

So the E2 elimination competes with the Sn2 anytime our nucleophile can be a strong base; because we are using hydroxide in this case, for sure that competition is going to be there.1532

E2 is favored in that case; of course, if it is tertiary, there is no chance of having the Sn2; so that is favored as well.1546

Remember if you have a phenyl or a vinyl alkyl halide, we can't do our Sn2 mechanism there because he is on an sp2 hybridized carbon.1553

A leaving group on an sp2 hybridized carbon is not what we have for backside attack; for backside attack, we need a tetrahedral carbon; we need an sp3 hybridized carbon.1564

It is a reaction of alkyl halides, not vinyl halides, not aryl halides; this would be no reaction.1573

Sn2 is one option for doing a substitution synthesizing an alcohol; we could also do an Sn1 reaction with water as our nucleophile.1581

This is a weaker nucleophile; water is not going to come and attack and do a one-step mechanism; but we can get a substitution via an Sn1 mechanism where we have a carbocation involved.1593

We call this reaction solvolysis because it is reacting with the solvent or more specifically hydrolysis since it is reacting with water.1605

What we need in this mechanism is... because we are forming a carbocation, this is going to be a reasonable option only if a favorable carbocation could be formed.1614

For example, if you have an allylic leaving group or benzylic or tertiary, those are all excellent carbocations; those would all be decent Sn1 mechanisms.1626

For example, we have this benzylic carbon with a leaving group; water is a weak nucleophile; that is why we are deciding that it cannot be the Sn2; it has to be the Sn1.1636

What mechanism is that?--what does that mean?--that means because there is no one here to attack, the leaving group just leaves on its own to give a carbocation to this electrophile.1650

We have water react as a nucleophile to an OH2; then we can deprotonate to get rid of that O+.1664

You could use the Br- here to tidy up; you might see that is sometimes; but really water, because we are doing hydrolysis, water is our solvent.1682

Water we have a lot of--that is probably going to be our best base here; we are going to get the alcohol.1689

Tell me about the stereochemistry here; what is the stereochemistry of this C-O bond?1697

Because the carbocation is planar, when water attacks, it can attack from the top face, it can attack from the bottom face.1705

Both of those are going to be equally likely; what we are going to get is a mixture of having the OH as a wedge and an OH as a dash.1711

So Sn1 is not a good situation with a chiral center unless it is okay to have a racemic mixture; then Sn1 is good.1720

But if you want stereocontrol then you need to find something like an Sn2 where you can do that backside attack; here we would get racemic mixture.1729

The other thing to keep in mind with water and trying to do an Sn1 mechanism is that, because you have a carbocation in your mechanism, it can rearrange.1741

If it is not one of these very very stable carbocations like in this case, we would get a positive charge here.1749

We might think that we could, when we do hydrolysis, we might get an OH in this position.1760

But in fact we don't because we are right next to a more substituted carbon; if the carbocation could somehow get over there, then it would be a more stable carbocation.1767

That in fact is the major product we get with rearrangement; we get this substituted product; we always have to keep that in mind.1780

Anytime we want to invoke a mechanism involving the carbocation, we have to make sure that, if there is a possibility of rearrangement, we account for that and that needs to be the product that we are expecting.1790

This is a good mechanism for you to try; see if you can do that complete Sn1 mechanism involving the carbocation rearrangement.1801

Another reaction we have seen in the past that gives an alcohol product is starting with an alkene starting material.1810

If you add water across an alkene double bond, you will end up with an alcohol product.1819

For hydration, remember we saw three different methods for adding water across a π bond.1825

If we used either H3O+ or this one, oxymercuration-reduction or oxymercuration-demercuration; this was the case where we broke the π bond; we add an H and an OH.1831

Where did hydrogen go?--both of these follow Markovnikov's rule; meaning the carbon with the hydrogen over here gets the hydrogen.1844

This last method, hydroboration-oxidation, this two-step method does the opposite regiochemistry.1858

We break the π bond; we add an H to the more substituted carbon, an OH to the less substituted carbon; we add the hydrogen to the carbon without the hydrogens; we have our CH3 there.1864

Our regiochemistry is different here; how about the stereochemistry?--is there anything we knew about the stereochemistry here with the hydroboration?1880

Do you remember that mechanism--hydroboration?--both the hydrogen and boron are added at the same time which means we have to add to the same face.1889

So another result of this is also we get syn addition; that means we need to show the H and the OH coming from the same face.1896

For example, they could be both wedges which forces this methyl group to be a dash; of course, it can come from the opposite face; it can come underneath.1903

Then we would get the enantiomer in which the H and the OH are the dashes and the methyl group is the wedge.1912

When we take a look at these products, we see that this is an alcohol product that we get; so another way that we can maybe put in an OH group on a carbon chain is to start with a double bond.1920

Then we could put the OH maybe on one carbon or the other depending on the reaction conditions we use, the reagents we use.1934

We could also do an oxidation reaction of an alkene; that would give a diol; for example, KMnO4 or if we use OsO4.1942

This was one of the several oxidations we studied for alkenes; this is the one that broke a π bond and did a dihydroxylation and added two OH groups.1951

It added them to the same face; again we would show some stereochemistry here; OH up, OH up; which then forces this methyl group down.1962

We call that syn dihydroxylation; if the it came from the bottom face, that would be the enantiomer.1973

This makes a special kind of alcohol; this makes a diol where we have two OH groups, one right next to each other.1980

If we have that special kind of target molecule, we can consider doing a dihydroxylation of an alkene.1988

Another great way to make an alcohol is to start from a ketone or an aldehyde; in other words, if I had a carbonyl on my carbon chain, that could get converted to an alcohol group.1996

The way we do this is we react it with a nucleophile of some kind because an aldehyde or a ketone... we are going to be studying these later.2009

We will see that these are electrophiles; they are electrophiles because this carbon-oxygen bond of course is polar because oxygen is electronegative.2018

It is also very polar because this has resonance; that has a resonance form with an O- and a C+.2026

As a result, the carbonyl carbon is very... remember this is called a carbonyl; I am going to be using that word a lot; that means the C-O double bond; it is a good word to know.2032

A carbonyl has the following polarity--a partial positive on the carbonyl carbon, partial negative on the carbonyl oxygen; that makes this carbonyl carbon a very good electrophile.2044

If you were to react it with a nucleophile, what happens is it attacks the carbon and it breaks this π bond and puts those electrons up onto the oxygen; we get some kind of intermediate like this.2056

If we were to then treat this with H3O+, some kind of workup procedure, at the end of the reaction, we are going to provide it with some kind of acid, some kind of proton source.2074

What will happen is we can protonate that O- with our work up and convert it to an OH group.2086

When we have a nucleophile adding into a carbonyl, the product we get has a nucleophile now connected to the carbonyl carbon and an OH group where the carbonyl oxygen used to be, the C-O double used to be.2097

Our product here is an alcohol; so this is another very good way to synthesize an alcohol and to come up with an OH as part of our final structure.2111

What nucleophile do we have available to us?--there is several we can look at; one nucleophile we have already seen is this acetylide ion.2126

He would be a very good nucleophile; we saw him doing Sn2s with alkyl halides; but he would also like to add into a carbonyl; he would be good at that.2133

But there is some other nucleophiles that we will be studying this unit that we have not yet seen.2142

This one is called a Grignard; it has an R group; that means some kind of carbon chain with a magnesium and a halide.2148

Anhydride, an example of that is something like LiAlH4; we are going to look at these new reagents and learn something more about their reactivities and what they do.2155

Here we see a C-; I can see how that is going to be a good nucleophile; but what about RMgX?--how do we get a nucleophile out of that?2167

This magnesium has a +2; the chloride, if you think about their oxidation state, the chloride has a -1.2176

That gives the alkyl group, this carbon group, the character of being a carbanion, being an R-.2185

We are going to be looking at things like this Grignard reagent as a source of R-; that would be a very good nucleophile.2193

Anhydride, as given as an example with this reagent, anhydride means we have an H with a lone pair and a negative charge; that would also be a very good nucleophile.2201

We are going to be adding maybe an alkyne group here or an R group here or a hydrogen here to be this final group in the position of where the carbonyl used to be.2212

Let's talk about this RMgX; it is an example of what is known as an organometallic reagent; it is called that because it has both an organic part and a metal.2226

M just represents some sort of metal; an R group is usually some organic component, some carbon chain; these are called organometallic reagents.2236

We are going to two examples of them; one is called RMgX; it has the formula of RMgX; one is RLi.2247

The first thing that we will do is we will talk about how to prepare them; where do they come from?--they are going to be prepared from an alkyl halide, a carbon chain with a halogen on it.2253

For example, if we were to take methyl bromide or bromomethane and react it with magnesium metal.2264

Here you are literally taking shavings of magnesium metal, magnesium turnings, tossing them into your reactions, stirring that reaction, heating it.2270

You will see your magnesium metal dissolve as it reacts; what it does is it inserts itself into the carbon-bromine bond; this is not a mechanism that we are going to worry about.2279

But we want to know what the product looks like; that is where we insert a magnesium into the carbon-bromine bond.2290

The other product here is going to be some salts; we are going to lose the bromide; we are going to make magnesium; that is not too important.2297

What we just said about this guy... he is called a Grignard reagent by the way, named after the chemist who developed the reagent; it has the general formula of RMgX.2308

This R in this case is just a methyl group; we will we see it could be just about anything.2322

The X is very often a bromide; but it also can be a chloride or a iodide; you can have another halogen there as well.2326

As we just mentioned, since the magnesium has a +2 and the bromine has a -1 as their oxidation state and the Grignard is a neutral molecule, that means the carbon has a -1 oxidation state.2334

These are not ionic compounds; you can think of this as having a combined partial +1 and this has a partial -1.2350

If you want to think of it as a partial charge rather than a full ionic charge, either one of those ways to consider it would be good.2359

Because it is a carbon with a negative charge, that means he would be a very good nucleophile; what is interesting is we just came from methyl bromide.2371

What kind of reactivity does methyl bromide have?--here we have a -1 for the bromine; we had a partial positive for this carbon.2378

We went from an electrophilic carbon, and then by attaching a metal to it, we turn it into a nucleophilic carbon.2388

That is what organometallic reagents looks like and that is how they behave--is that any carbon bearing a metal has negative charge character, anionic character.2395

The Grignard is one option; we get that when we react an alkyl halide with a magnesium metal.2404

If we did lithium metal instead, what happens is we do a halogen metal exchange; where we used to have the halogen, we now have a lithium.2409

If we consider the nature of this methyl group, this carbon, what kind of charge do you associate with a lithium?--what is the oxidation state of a lithium?2420

+1; we could say partial +1 if you would like; which again makes this carbon partial -1; this is another example of a nucleophile; all organometallic reagents are going to be nucleophilic.2429

Unfortunately he doesn't have a cool name like the Grignard; this is just called an organolithium... an organolithium reagent.2442

It has this general formula of some kind of carbon group with a lithium attached; we call those organolithiums.2451

What is great about these Grignard reagents, organolithium reagents, and organometallics in general is this R group that you are having the metal attached.2459

The R can be almost anything you can imagine; it can be an alkyl group just like we saw here; here we have a methyl; here we have a carbon chain.2468

You could attach a metal to a random sp3 hybridized carbon group; but you can also have aryl Grignards or aryl lithiums, phenyl lithiums, for example.2475

You can have a metal attached to an sp2 hybridized carbon; or vinyl, you could have it part of a double bond.2484

So huge variety in the types of carbon groups that can be attached to a metal and therefore be nucleophilic.2491

When it comes to synthesis, these organometallic reagents are really going to open up the door for us for making all sorts of interesting and new molecules.2498

Let's think about the reactions that an organometallic might undergo; we just learned how to make them; how do they behave?--what can they do?2506

One reaction that they have is that they are extremely strong bases; in other words, they can be protonated.2515

If we have this magnesium chloride on this carbon chain and we react it with an alcohol like this; we just learned how alcohols can be acidic.2522

This is an acid; this is a very strong base; we are going to get a proton transfer reaction to take place.2534

One way we can show this reacting, sometimes we just see the arrow coming from this carbon metal bond.2542

But I think an easier way to do the mechanism for these is wherever you had the metal attached, you treat that carbon as if it has a lone pair and a negative charge.2549

It doesn't really; it is not an ionic species; but that is a very helpful way to view it; it is a very helpful way to show mechanisms.2560

What we do is we will just put quotes around this species saying we don't really have this but it acts just like it; the quotes let us get away with that.2568

Now we can see this base; clearly it has a lone pair and a negative charge like other bases do; we can clearly see how we can do that proton transfer.2577

The base grabs the proton, leaves the electrons behind; the product we get is my cyclopentyl group--has been protonated; we have a proton in that position.2586

We also made some methoxide here; we deprotonated the alcohol and we protonated the Grignard in this case; what is the salt here?--this is going to be like an MgBr salt of the alkoxide.2598

Typically this is a side reaction; this is not a valuable reaction; this is something we are going to try to avoid.2617

What is very important to know is that Grignards will react with water; just like it will react with alcohol--has an acidic proton; water certainly has an acidic proton.2624

We must use very dry glassware, dry solvents; we can flame dry our glassware to get rid of any residual moisture that might be attached to it.2633

We will store our glassware in an oven to keep it super dry; then set up the reaction under argon or nitrogen, some inert atmosphere, so that it is nice and dry.2642

Our solvents, we will put some drying agents or we will freshly distill it so it is super dry.2654

Any bit of moisture in our reaction mixture or in our atmosphere has the potential of quenching our Grignard reaction, of reacting with a Grignard reagent and destroying it.2660

We are going to be very careful to do this kind of reaction in the appropriate conditions.2671

Of course when it comes to a solvent that we are using, we can't use a protic solvent like water or an alcohol because the Grignard cannot exist in those conditions.2677

Instead we need to use aprotic solvents; things like ethers, diethyl ether, THF stands for tetrahydrofuran--has this formula; some kind of ether is going to be used.2686

Again we should get used to these names of solvents because it is going to be very commonly part of your reaction conditions--is listing the solvent.2699

You don't want to worry too much about that when you see it or try to use it somehow as a reagent; it is just a solvent; all of our reactions have solvents associated with them.2707

There is one way we can make this a useful reaction; that is if we wanted to introduce a hydrogen into our structure or maybe even a deuterium.2718

Deuterium, which is what D stands for, is an isotope of hydrogen that has a neutron in here; it is H2.2733

It is so commonly used, instead of call it H2, we usually just use the letter D to represent deuterium.2743

Sometimes we want to include isotopic labels in a structure; this would be a way that we can do something like that.2750

For example, if we had a bromine here on our benzene ring and we reacted this with magnesium, that would insert a magnesium and turn this Br group into an MgBr group.2757

Then what would happen if we reacted this with D2O, deuterated water, instead of H2O?2769

We would expect that phenyl minus to protonate, deuterate in this case, add a D+; therefore you can get a deuterium installed in your structure; it can be a useful reaction.2774

But by in large, the reaction with alcohols and water just help us, guide us in our experimental conditions to make sure we avoid those so that the side reactions don't happen.2788

Where we are typically going to be using our organometallic reagents like a Grignard is as a strong nucleophile; this is where it is most useful; which means it reacts with an electrophile.2802

An electrophile like a carbonyl, not alkyl halides; we have seen those as electrophiles before; but these do not react with Grignards; we will see an example of that.2812

For example, let's say we had methyl lithium and cyclohexanone with some THF; what if we mixed all those together?2825

The methyl lithium, remember this is like having a CH3-; the lithium gives us a + charge; that means it is like we have a CH3---definitely a nucleophile.2833

I am going to put that in quotes to remind myself it is not really ionic; but it reacts kind of like that.2845

Is the carbonyl in this ketone, is the carbonyl an electrophile?--absolutely, this carbonyl carbon remember is always partially positive.2853

We will be seeing dozens of cases of that when we study carbonyls; what happens when you mix these two?2862

This is going to attack the carbonyl and break the π bond... I moved that up a little higher... going to attack the carbonyl carbon and break the π bond.2870

It doesn't matter if you show it coming from the right or left; but it is going to give me an O- where the carbonyl used to be.2882

Then after work up, step two is work up, I am going to protonate that O-; and I just synthesized what kind of functional group?--I just made an alcohol.2891

This would be a nice way to synthesize an alcohol; furthermore, notice what we just did here--because we had a carbon nucleophile and a carbon electrophile, we just made a new carbon-carbon bond.2909

Again that is unique in organic chemistry; that is a pretty special reaction to study; that is going to be extremely useful.2921

Grignards are extremely useful organolithiums for making alcohols and creating new carbon chains in the process.2928

Let's take a look at this example; we have methyl bromide; methyl bromide is definitely an electrophile because we have a carbon bearing a leaving group.2938

Phenyl magnesium bromide, what does that mean?--we have phenyl minus, put that in quotes.2947

It is just like having a phenyl ring with a lone pair and negative charge on one of the carbons, a strange looking species but that is how it behaves.2955

What would be very tempting here, what makes sense, is we can have this attack the carbon and kick off the leaving group; very tempting to do; however it does not happen.2965

That is just an exception that we really need to get used to seeing is that Grignards do not react with an alkyl halide.2980

Grignards... when I say Grignard, I mean Grignard organolithium; they are pretty much going to be used interchangeably for most of our reactions.2989

Grignards don't do Sn2s; they don't do Sn2 mechanisms; they are not there to react with an alkyl halide.2998

Remember how did you make this Grignard?--you started with the halide; we use alkyl halides or any kind of halide to prepare a Grignard.3008

That would not work at all if the Grignard, as it was being formed, started to react with the starting material.3018

They are compatible with each other; Grignards and organolithiums will not react with alkyl halides.3023

We are just going to have to try to keep that straight because it is really a reaction that is a logical one and one in fact that a lot of students make mistakes for in doing so.3028

But we just need to remember that this is the one reaction Grignards don't do; they are going to react with carbonyls but not with alkyl halides.3040

The other nucleophile we will take a look at for synthesizing alcohols is the hydride nucleophile; hydride again means we have an H with a lone pair and a negative charge.3054

Typically for the reagents we are going to be seeing, especially when it is being nucleophilic... again we are going to put that in quotes.3067

Because these are not ionic species; the hydrogen minus is not floating around on its own; it is always going to be coordinated to a metal.3073

We are going to either use lithium aluminum hydride or sodium borohydride; you could see how similar these species are.3081

That aluminum is going to take one of the hydrogens and deliver it or the boron is going to deliver a hydrogen; but it is going to react as if it was an H-.3090

Let's see an example; if we start with a ketone or an aldehyde, we start with a carbonyl and we react it with lithium aluminum hydride.3100

This actually is often abbreviated LAH for lithium aluminum hydride; in step one, if we react this with LAH, that gives us a source of H-.3107

This is one of those cases where really saying the name of the reagent and thinking about the name of the reagent is going to help us predict the product.3119

The name of the reactive species is part of the name; it is lithium aluminum hydride--right there we see that we have H-; that means we have a nucleophile.3126

We need to look around for an electrophile; this carbonyl will be our electrophile; we attack the carbon and break the π bond; carbonyls do the same thing all the time.3135

We now have a hydrogen attached and an O-; just like with the Grignard, we are going to follow this up with a reaction to get rid of the O-.3151

We are going to do step two as some kind of aqueous work up; step two, we protonate; and our product is an alcohol.3163

This is described as a reduction reaction; we could describe this as a hydride reduction because we increase the number of C-H bonds while decreasing the number of C-O bonds.3182

Ketones and aldehydes can be reduced with a hydride reagent, either lithium aluminum hydride or sodium borohydride, to give as a result an alcohol product.3203

Let's see a few examples of this; we just saw one with lithium aluminum hydride; with LAH, we need a two-step process.3217

First we react with LAH; then we react with H3O+; we do a work up.3224

NaBH4 is less reactive; this is less reactive than LAH; so we don't need to do a stepwise approach; we can actually use as our solvent a protic solvent.3229

The NaBH4 is going to be donating our H-; the methanol here is going to be donating the H+ at the end.3244

It is going to available for, instead of a separate workup step; it is going to be our final protonation step.3253

What happens, same thing as LAH; we attack the carbonyl; let's see if we could just draw a product; we have our nucleophile added to the carbonyl carbon; what used to be the carbonyl is now an OH.3260

We have that same pattern each time whether it is a Grignard or a hydride; we add the hydrogen, we add the nucleophile to the carbonyl and our carbonyl is now an OH.3275

Let's try one more; how about if we took this ketone and we react it with hydride and alcohol; we expect to reduce the carbonyl from a ketone to an alcohol; we could do the mechanism for that.3286

What happens with this alcohol then if we treat it with H2SO4 and heat?--we saw that as a dehydration reaction.3306

This is a way to remove water from an alcohol and form an alkene, form a carbon-carbon double bond.3316

Let's think about the regiochemistry; is there more than one alkene that is possible?--where would the best one be?3324

We have our leaving group here; but our carbocation remember can go anywhere it wants because those can rearrange; so what would be the best location of the double bond in our final product?3331

I think we are going to want to go here so that the double bond is now conjugated with the double bonds that are already here in the benzene ring.3347

This is the major product; it is more stable than having the double bond in this position, in the vertical position, more stable because it is conjugated with the existing π bonds.3356

That means it has resonance; we can have delocalization of these π electrons; we have p orbital, p orbital, p orbital, p orbital; we have all these p orbitals are linked.3375

We can have resonance and delocalization of that alkene; that is going to be a more stable case because it is conjugated.3384

Remember Zaitsev's rule; Zaitsev's rule tells us that the more stable alkene is always going to be our major alkene.3393

Let's look at a few more examples; how about if we wanted to do this transformation?--here we have a one carbon chain; my carbonyl is now an OH and we have a new carbon here.3405

Let's draw this in as a methyl group, as a CH3, expand our line drawing; it looks like this is a new group that is here, that has been added.3422

If we wanted to react with this carbonyl carbon, we know that this is electrophilic; this is partially positive so it is electrophilic.3431

What we need to react with that carbon is we need a methyl that is a nucleophile; how can we make a methyl be nucleophilic?3441

I think all we need to do, if we had a lone pair and a negative charge, that would make it nucleophilic; how do we get to that reactivity and that species?3454

That is exactly what a Grignard reagent does; if we have CH3MgBr, that is nucleophilic; that would react with the carbonyl; we would do that as step one.3465

As step two, after the Grignard, we would need some kind of aqueous work up, H3O+ for example; that would protonate the O- to give an alcohol product.3478

More than doing just a simple reduction of the carbonyl, we also added in a new carbon group; this is how we could use our Grignard reagent.3490

Here is another example with an organometallic; where does this alkyl lithium come from?--how do we make an organometallic?3499

What will we make this, if we ask what starting materials do we need?--we are seeing the reaction conditions here; we have added in lithium metal; what did that lithium metal react with?3509

What did we need in that position?--we needed a halogen of some kind; we need an RX to go to an alkyl lithium or Grignard reagent too.3524

You can pick any halide you want--bromide, chloride, iodide; they would all do a good example.3537

The Grignard and the hydride reagents are new reactions, reaction with a carbonyl; those are new reagents that are very useful in forming the alcohol functional group.3545

That is useful; that is a new strategy for synthesizing alcohols; we can add that to our list of other reagents where we are doing more of a functional group in our conversion.3557

Going maybe from an alkyl halide to an alcohol or from an alkene to an alcohol by doing those sort of transformations as well.3568

The next part of the alcohol unit is going to look at reactions of alcohols; once we have an OH on a structure, what manipulations can we do to it?--what transformations can it undergo?3577

Thank for coming to Educator.com; I will see you again soon.3590

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