Organic chemistry : an acid-base approach

1500 Pages·2011·24.47 MB·English

by  Smith

ORGANIC
CHEMISTRY
An Acid–Base Approach
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ORGANIC
CHEMISTRY
An Acid–Base Approach
M I C H A E L B . S M I T H
Boca Raton London New York
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Version Date: 20110720
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Preface.................................................................xi
Acknowledgments............................................xv
The Author.......................................................xvii Contents
Chapter 1: Introduction....................................1
1.1 A Brief History of Organic Chemistry
1.2 The Variety and Beauty of Organic Molecules
Chapter 2: Why Is an Acid–Base
Theme Important?............................................19
2.1 Acids and Bases in General Chemistry
2.2 Acids and Bases in Organic Chemistry
2.3 How Are the Two Acid–Base
Definitions Related?
2.4 Acid and Base Strength
2.5 Lewis Acids and Lewis Bases
2.6 Why Is Acid–Base Chemistry a Theme
for Organic Chemistry?
2.7 Biological Relevance
Chapter 3: Bonding..........................................45
3.1 The Elements
3.2 What Is a Chemical Bond? Ionic versus Covalent
3.3 The Covalent Carbon–Carbon Bond
3.4 Molecular Orbitals
3.5 Tetrahedral Carbons and sp3 Hybridization
3.6 How Strong Is a Covalent
Bond? Bond Dissociation Energy
3.7 Polarized Covalent σ-Bonds
3.8 Biological Relevance
Chapter 4: Alkanes, Isomers, and an
Introduction to Nomenclature.......................87
4.1 The Fundamental Structure of
Alkanes Based on the sp3 Hybrid Model
4.2 Millions of Hydrocarbons: Alkanes
4.3 Combustion Analysis and Empirical Formulas
4.4 The Acid or Base Properties of Alkanes
4.5 Isomers
4.6 Naming Millions of Isomers:
Rules of Nomenclature. The
IUPAC Rules of Nomenclature
4.7 Rings Made of Carbon. Cyclic Compounds
4.8 Biological Relevance
Chapter 5: Functional Groups.....................121
5.1 Introducing a Functional Group: Alkenes
5.2 Another Hydrocarbon Functional Group: Alkynes
5.3 Hydrocarbons with Several Multiple Bonds
5.4 Reactivity of Polarized Covalent σ-Bonds
5.5 Formal Charge
v
vi Organic Chemistry: An Acid-Base Approach
5.6 Heteroatom Functional Groups
5.7 Acid–Base Properties of Functional Groups
5.8 Polarity and Intermolecular Forces
5.9 Functional Groups with Polarized π-Bonds
5.10 Benzene: A Special Cyclic Hydrocarbon
5.11 Biological Relevance
Chapter 6: Acids, Bases, Nucleophiles, and Electrophiles...................191
6.1 Acid–Base Equilibria
6.2 Polarized Hydrogen–Heteroatom Bonds: Acidic Units
6.3 Factors That Influence the Strength of a Brønsted–Lowry Acid
6.4 Organic Bases
6.5 Lewis Acids and Lewis Bases
6.6 A Positive Carbon Atom Can Accept Electrons
6.7 Nucleophiles
6.8 Biological Relevance
Chapter 7: Chemical Reactions, Bond Energy, and Kinetics..............249
7.1 A Chemical Reaction
7.2 Bond Dissociation Enthalpy and Reactions
7.3 Transition States
7.4 Reactive Intermediates
7.5 Free Energy. Influence of Enthalpy and Entropy
7.6 Energetics. Starting Materials, Transition States, Intermediates,
and Products on a Reaction Curve
7.7 Competing Reactions
7.8 Mechanisms
7.9 Why Does a Chemical Reaction Occur? Defining a “Reactive” Center
7.10 Reversible Chemical Reactions
7.11 Kinetics
7.12 No Reaction
7.13 Biological Relevance
Chapter 8: Rotamers and Conformation..................................................295
8.1 Rotamers
8.2 Longer Chain Alkanes: Increased Torsional Strain
8.3 Conformations of Alkenes and Alkynes: Introducing π-Bonds
8.4 Influence of Heteroatoms on the Rotamer Population
8.5 Cyclic Alkanes
8.6 Substituted Cyclohexanes
8.7 Larger Rings
8.8 Cyclic Alkenes
8.9 Introducing Heteroatoms into a Ring
8.10 Biological Relevance
Chapter 9: Stereoisomers: Chirality, Enantiomers,
and Diastereomers..........................................................................................353
9.1 Stereogenic Carbons and Stereoisomers
9.2 Specific Rotation: A Physical Property
9.3 Absolute Configuration (R and S Nomenclature)
9.4 Alkenes
9.5 Diastereomers
Contents vii
9.6 Stereogenic Centers in Cyclic Molecules
9.7 Stereogenic Centers in Complex Molecules
9.8 Optical Resolution
9.9 Biological Relevance
Chapter 10: Acid–Base Reactions of π-Bonds..........................................415
10.1 Alkenes and Acid–Base Chemistry
10.2 Carbocation Intermediates
10.3 Alkenes React with Weak Acids in the Presence of an Acid Catalyst
10.4 Alkenes React as Lewis Bases
10.5 Alkenes React as Lewis Bases with Electrophilic Oxygen.
Oxidation of Alkenes to Oxiranes
10.6 Alkynes React as Brønsted–Lowry Bases or Lewis Bases
10.7 Reactions That Are Not Formally Acid–Base Reactions
10.8 Non-ionic Reactions: Radical Intermediates and Alkene Polymerization
10.9 Synthetic Transformations
10.10 Biological Relevance
Chapter 11: Nucleophiles: Lewis Base-Like Reactions
at sp3 Carbon..................................................................................................503
11.1 Alkyl Halides, Sulfonate Esters, and the Electrophilic C–X Bond
11.2 Nucleophiles and Bimolecular Substitution (the S 2 Reaction)
N
11.3 Functional Group Transformations via the S 2 Reaction
N
11.4 A Tertiary Halide Reacts with a Nucleophile When the Solvent Is Water
11.5 Carbocation Rearrangements
11.6 Solvolysis Reactions of Alkyl Halides
11.7 Preparation of Halides and Sulfonate Esters by Substitution Reactions
11.8 Reactions of Ethers
11.9 Free Radical Halogenation of Alkanes
11.10 Applications to Synthesis
11.11 Biological Relevance
Chapter 12: Base-Induced Elimination Reactions.................................583
12.1 Bimolecular Elimination
12.2 Stereochemical Consequences of the E2 Reaction
12.3 The E2 Reaction in Cyclic Molecules
12.4 Unimolecular Elimination
12.5 Intramolecular Elimination
12.6 1,3 Elimination: Decarboxylation
12.7 Elimination Reactions of Vinyl Halides: Formation of Alkynes
12.8 Elimination Functional Group Exchanges
12.9 Biological Relevance
Chapter 13: Substitution and Elimination Reactions Can Compete......621
13.1 A Few Simplifying Assumptions
13.2 Protic versus Aprotic and Water
13.3 Nucleophilic Strength versus Base Strength
13.4 The Nature of the Halide
13.5 What about Secondary Halides?
13.6 Strength and Limitations of the Simplifying Assumptions
13.7 When Do the Assumptions Fail?
viii Organic Chemistry: An Acid-Base Approach
Chapter 14: Spectroscopic Methods of Identification...........................641
14.1 Light and Energy
14.2 Mass Spectrometry
14.3 Infrared Spectroscopy
14.4 Nuclear Magnetic Resonance Spectroscopy
14.5 The Structure of an Unknown Molecule May Be Determined
14.6 Carbon-13 NMR Spectroscopy: Counting the Carbons
14.7 Biological Relevance
Chapter 15: Organometallic Reagents......................................................741
15.1 Introducing Magnesium into a Molecule
15.2 Reaction of Aryl and Vinyl Halides with Magnesium
15.3 Grignard Reagents Are Bases
15.4 Grignard Reagents Are Poor Nucleophiles with Alkyl Halides
15.5 Organolithium Reagents
15.6 Organocuprates
15.7 Organometallic Disconnections
15.8 Biological Relevance
Chapter 16: Carbonyl Compounds: Structure,
Nomenclature, Reactivity....................................................................................769
16.1 The Carbonyl Group
16.2 Aldehydes and Ketones. Nomenclature
16.3 Chemical Reactivity of Ketones and Aldehydes
16.4 Carboxylic Acids. Nomenclature and Properties
16.5 Dicarboxylic Acids
16.6 Dicarboxylic Acids Have Two pK Values
a
16.7 Carboxylic Acid Derivatives. Nomenclature and Properties
16.8 Acyl Substitution with Carboxylic Acid Derivatives
16.9 Sulfonic Acids
16.10 Biological Relevance
Chapter 17: Oxidation...................................................................................811
17.1 Defining an Oxidation
17.2 Oxidation of Alcohols with Chromium(VI)
17.3 Oxidation of Alkenes
17.4 Oxidative Cleavage
17.5 Summary of Functional Group Exchanges
17.6 Biological Relevance
Chapter 18: Reactions of Aldehydes and Ketones..................................843
18.1 Chemical Reactivity of the Carbonyl Group
18.2 Reversible versus Irreversible Acyl Addition
18.3 Reaction of Aldehydes or Ketones with Strong Nucleophiles
18.4 Organometallic Reagents Are Nucleophiles
18.5 Water: A Weak Nucleophile That Gives Reversible Acyl Addition
18.6 Alcohols: Neutral Nucleophiles That Give Reactive Products
18.7 Amines Are Nucleophiles That React to Give Imines or Enamines
18.8 Carbon–Carbon Bond-Forming Reactions and Functional Group Modification
18.9 Biological Relevance
Contents ix
Chapter 19: Reduction..................................................................................905
19.1 Defining a Reduction
19.2 Hydrides as Reducing Agents
19.3 Catalytic Hydrogenation
19.4 Dissolving Metal Reductions
19.5 Summary of Functional Group Exchanges
19.6 Biological Relevance
Chapter 20: Carboxylic Acid Derivatives and Acyl Substitution........943
20.1 Chemical Reactivity of Carboxylic Acid Derivatives
20.2 Acyl Substitution. Acid Derivatives React with Water: Hydrolysis
20.3 Preparation of Acid Chlorides
20.4 Preparation of Acid Anhydrides
20.5 Preparation of Esters
20.6 Amides
20.7 The Reaction of Carboxylic Acid Derivatives with Carbon Nucleophiles
20.8 Reaction of Organometallics with Other Electrophilic “Carbonyl” Molecules
20.9 Dicarboxylic Acid Derivatives
20.10 Baeyer–Villiger Oxidation
20.11 Sulfonic Acid Derivatives
20.12 Sulfate Esters and Phosphate Esters
20.13 Nitriles Are Carboxylic Acid Derivatives
20.14 Carbon–Carbon Bond-Forming Reactions and Functional
Group Exchanges of Acid Derivatives
20.15 Biological Relevance
Chapter 21: Aromatic Compounds and Benzene Derivatives............1027
21.1 Benzene and Aromaticity
21.2 Functionalized Benzene Derivatives and a New Nomenclature System
21.3 Electrophilic Aromatic Substitution
21.4 Disubstituted Benzene Derivatives
21.5 Polysubstituted Benzene Derivatives
21.6 Reduction of Aromatic Compounds
21.7 Aromaticity in Monocyclic Molecules Other Than Benzene
21.8 Polynuclear Aromatic Hydrocarbons
21.9 Aromatic Amines and Diazonium Salts
21.10 Nucleophilic Aromatic Substitution
21.11 Aromatic Disconnections and Functional Group Exchange Reactions
21.12 Synthesis of Aromatic Compounds
21.13 Biological Relevance
Chapter 22: Enolate Anions: Acyl Addition and Acyl Substitution .....1119
22.1 Aldehydes and Ketones Are Weak Acids
22.2 Enolate Anions Are Nucleophiles. The Aldol Condensation
22.3 Non-Nucleophilic Bases
22.4 Enolate Anions from Unsymmetrical Ketones
22.5 Dehydration of Aldol Products
22.6 The Intramolecular Aldol Condensation
22.7 Ester Enolates
22.8 Decarboxylation
22.9 Enolate Alkylation
22.10 Phosphorus Ylids and the Wittig Reaction
22.11 Many New Synthetic Possibilities
22.12 Biological Relevance