Organic Chemistry FOURTH EDITION Maitland Jones,Jr. NEW YORK UNIVERSITY Steven A.Fleming TEMPLE UNIVERSITY G W.W.Norton Company New York London
Organic Chemistry FOURTH EDITION Maitland Jones, Jr. NEW YORK UNIVERSITY Steven A. Fleming TEMPLE UNIVERSITY W. W. N o r t o n & C o m p a n y N e w Yo r k • L o n d o n
Drawing structures and reactions is critical to understanding them.The front and back covers show chair cyclohexanes,which are introduced in Chapter 5 and appear over and over again in the natural world. These structures were hand-drawn and have ever-so-small imperfections.Evaluate these chairs,and after you finish Chapter 5,we suggest you take a very close look to see how you might improve them. W.W.Norton&Company has been independent since its founding in 1923,when William Warder Norton and Mary D.Herter Norton first published lectures delivered at the People's Institute,the adult education division of New York City's Cooper Union.The Nortons soon expanded their program beyond the Institute, publishing books by celebrated academics from America and abroad.By mid-century,the two major pillars of Norton's publishing program-trade books and college texts-were firmly established.In the 1950s,the Norton family transferred control of the company to its employees,and today-with a staff of four hundred and a comparable number of trade,college,and professional titles published each year-W.W.Norton Company stands as the largest and oldest publishing house owned wholly by its employees. Copyright 2010,2005,2000,1997 by W.W.Norton Company,Inc. All rights reserved Printed in the United States of America Editor:Erik Fahlgren Project editor:Carla L Talmadge Marketing manager:Kelsey Volker Editorial assistant:Mary Lynch Production manager:Chris Granville Managing editor,College:Marian Johnson Ancillaries editor:Matthew A.Freeman Media editor:Rob Bellinger Developmental editor:Irene Nunes Design director:Rubina Yeh Photo editor:Junenoire Mitchell Cover design:John Hamilton Composition:Prepare,Inc. Illustration studio:Penumbra Design,Inc. Manufacturing:Transcontinental Interglobe Library of Congress Cataloging-in-Publication Data Jones,Maitland,1937- Organic chemistry/Maitland Jones,J-4th ed./Steven A.Fleming. p.cm. Includes bibliographical references and index. ISBN978-0-393-93149-5(hardcover) 1.Chemistry,Organic-Textbooks.I.Fleming.Steven A.II.Title. QD253.2.J662010 547-dc22 2009033807 W.W.Norton Company,Inc.,500 Fifth Avenue,New York,N.Y.10110 www.wwnorton.com W.W.Norton Company Ltd.,Castle House,75/76 Wells Street,London W1T 3QT 1234567890
Drawing structures and reactions is critical to understanding them. The front and back covers show chair cyclohexanes, which are introduced in Chapter 5 and appear over and over again in the natural world. These structures were hand-drawn and have ever-so-small imperfections. Evaluate these chairs, and after you finish Chapter 5, we suggest you take a very close look to see how you might improve them. W.W. Norton & Company has been independent since its founding in 1923, when William Warder Norton and Mary D. Herter Norton first published lectures delivered at the People’s Institute, the adult education division of New York City’s Cooper Union. The Nortons soon expanded their program beyond the Institute, publishing books by celebrated academics from America and abroad. By mid-century, the two major pillars of Norton’s publishing program—trade books and college texts—were firmly established. In the 1950s, the Norton family transferred control of the company to its employees, and today—with a staff of four hundred and a comparable number of trade, college, and professional titles published each year—W.W. Norton & Company stands as the largest and oldest publishing house owned wholly by its employees. Copyright © 2010, 2005, 2000, 1997 by W. W. Norton & Company, Inc. All rights reserved Printed in the United States of America Editor: Erik Fahlgren Project editor: Carla L. Talmadge Marketing manager: Kelsey Volker Editorial assistant: Mary Lynch Production manager: Chris Granville Managing editor, College: Marian Johnson Ancillaries editor: Matthew A. Freeman Media editor: Rob Bellinger Developmental editor: Irene Nunes Design director: Rubina Yeh Photo editor: Junenoire Mitchell Cover design: John Hamilton Composition: Prepare, Inc. Illustration studio: Penumbra Design, Inc. Manufacturing: Transcontinental Interglobe Library of Congress Cataloging-in-Publication Data Jones, Maitland, 1937– Organic chemistry / Maitland Jones, Jr.—4th ed. / Steven A. Fleming. p. cm. Includes bibliographical references and index. ISBN 978-0-393-93149-5 (hardcover) 1. Chemistry, Organic—Textbooks. I. Fleming, Steven A. II. Title. QD253.2.J66 2010 547—dc22 2009033807 W. W. Norton & Company, Inc., 500 Fifth Avenue, New York, N.Y. 10110 www.wwnorton.com W. W. Norton & Company Ltd., Castle House, 75/76 Wells Street, London W1T 3QT 1234567890
Brief Contents 1 Atoms and Molecules;Orbitals and Bonding 1 2 Alkanes 50 3 Alkenes and Alkynes 97 4 Stereochemistry 147 5 Rings 185 6 Alkyl Halides,Alcohols,Amines,Ethers, and Their Sulfur-Containing Relatives 223 7 Substitution and Elimination Reactions: The SN2,SN1,E1,and E2 Reactions 261 8 Equilibria 331 9 Additions to Alkenes 1 363 10 Additions to Alkenes 2 and Additions to Alkynes 409 11 Radical Reactions 467 12 Dienes and the Allyl System:2 Orbitals in Conjugation 511 13 Conjugation and Aromaticity 571 14 Substitution Reactions of Aromatic Compounds 623 15 Analytical Chemistry:Spectroscopy 694 16 Carbonyl Chemistry 1:Addition Reactions 762 17 Carboxylic Acids 828 18 Derivatives of Carboxylic Acids:Acyl Compounds 876 19 Carbonyl Chemistry 2:Reactions at the a.Position 931 20 Special Topic:Reactions Controlled by Orbital Symmetry 1030 21 Special Topic:Intramolecular Reactions and Neighboring Group Participation 1080 22 Special Topic:Carbohydrates 1124 23 Special Topic:Amino Acids and Polyamino Acids (Peptides and Proteins)1173
1 Atoms and Molecules; Orbitals and Bonding 1 2 Alkanes 50 3 Alkenes and Alkynes 97 4 Stereochemistry 147 5 Rings 185 6 Alkyl Halides, Alcohols, Amines, Ethers, and Their Sulfur-Containing Relatives 223 7 Substitution and Elimination Reactions: The SN2, SN1, E1, and E2 Reactions 261 8 Equilibria 331 9 Additions to Alkenes 1 363 10 Additions to Alkenes 2 and Additions to Alkynes 409 11 Radical Reactions 467 12 Dienes and the Allyl System: 2p Orbitals in Conjugation 511 13 Conjugation and Aromaticity 571 14 Substitution Reactions of Aromatic Compounds 623 15 Analytical Chemistry: Spectroscopy 694 16 Carbonyl Chemistry 1: Addition Reactions 762 17 Carboxylic Acids 828 18 Derivatives of Carboxylic Acids: Acyl Compounds 876 19 Carbonyl Chemistry 2: Reactions at the α Position 931 20 Special Topic: Reactions Controlled by Orbital Symmetry 1030 21 Special Topic: Intramolecular Reactions and Neighboring Group Participation 1080 22 Special Topic: Carbohydrates 1124 23 Special Topic: Amino Acids and Polyamino Acids (Peptides and Proteins) 1173 Brief Contents v
Contents Selected Applications xix Organic Reaction Animations xxi Preface to the Fourth Edition xxiii Introduction xxxiii 1 Atoms and Molecules;Orbitals and Bonding 1 1.1 Preview 2 1.2 Atoms and Atomic Orbitals 4 1.3 Covalent Bonds and Lewis Structures 13 1.4 Resonance Forms 22 1.5 Hydrogen(H2):Molecular Orbitals 30 1.6 Bond Strength 36 1.7 An Introduction to Reactivity:Acids and Bases 41 1.8 Special Topic:Quantum Mechanics and Babies 42 1.9 Summary 43 1.10 Additional Problems 45 2 Alkanes 50 2.1 Preview 51 2.2 Hybrid Orbitals:Making a Model for Methane 52 2.3 The Methyl Group(CH3)and Methyl Compounds(CH3X)60 2.4 The Methyl Cation(CH3),Anion(-:CH3),and Radical(CH3)62 2.5 Ethane(C2H),Ethyl Compounds(C2HsX), and Newman Projections 64 2.6 Structure Drawings 70 2.7 Propane(C3Hs)and Propyl Compounds(C3H-X)71 2.8 Butanes(C H10),Butyl Compounds(CaHoX), and Conformational Analysis 73 2.9 Pentanes(CsH12)and Pentyl Compounds(CsHiX)76 2.10 The Naming Conventions for Alkanes 78 vii
Selected Applications xix Organic Reaction Animations xxi Preface to the Fourth Edition xxiii Introduction xxxiii 1 Atoms and Molecules; Orbitals and Bonding 1 1.1 Preview 2 1.2 Atoms and Atomic Orbitals 4 1.3 Covalent Bonds and Lewis Structures 13 1.4 Resonance Forms 22 1.5 Hydrogen (H2): Molecular Orbitals 30 1.6 Bond Strength 36 1.7 An Introduction to Reactivity: Acids and Bases 41 1.8 Special Topic: Quantum Mechanics and Babies 42 1.9 Summary 43 1.10 Additional Problems 45 2 Alkanes 50 2.1 Preview 51 2.2 Hybrid Orbitals: Making a Model for Methane 52 2.3 The Methyl Group (CH3) and Methyl Compounds (CH3X) 60 2.4 The Methyl Cation (+ CH3), Anion (−:CH3), and Radical (·CH3) 62 2.5 Ethane (C2H6), Ethyl Compounds (C2H5X), and Newman Projections 64 2.6 Structure Drawings 70 2.7 Propane (C3H8) and Propyl Compounds (C3H7X) 71 2.8 Butanes (C4H10), Butyl Compounds (C4H9X), and Conformational Analysis 73 2.9 Pentanes (C5H12) and Pentyl Compounds (C5H11X) 76 2.10 The Naming Conventions for Alkanes 78 vii Contents
vili CONTENTS 2.11 Drawing Isomers 82 2.12 Rings 83 2.13 Physical Properties of Alkanes and Cycloalkanes 86 2.14 Nuclear Magnetic Resonance Spectroscopy 88 2.15 Acids and Bases Revisited:More Chemical Reactions 90 2.16 Special Topic:Alkanes as Biomolecules 92 2.17 Summary 93 2.18 Additional Problems 94 3 Alkenes and Alkynes 97 3.1 Preview 98 3.2 Alkenes:Structure and Bonding 99 3.3 Derivatives and Isomers of Alkenes 107 3.4 Nomenclature 110 3.5 The Cahn-Ingold-Prelog Priority System 112 3.6 Relative Stability of Alkenes:Heats of Formation 115 3.7 Double Bonds in Rings 118 3.8 Physical Properties of Alkenes 123 3.9 Alkynes:Structure and Bonding 123 3.10 Relative Stability of Alkynes:Heats of Formation 126 3.11 Derivatives and Isomers of Alkynes 126 3.12 Triple Bonds in Rings 128 3.13 Physical Properties of Alkynes 129 3.14 Acidity of Alkynes 129 3.15 Molecular Formulas and Degrees of Unsaturation 130 3.16 An Introduction to Addition Reactions of Alkenes and Alkynes 131 3.17 Mechanism of the Addition of Hydrogen Halides to Alkenes 132 3.18 The Regiochemistry of the Addition Reaction 137 3.19 A Catalyzed Addition to Alkenes:Hydration 139 3.20 Synthesis:A Beginning 141 3.21 Special Topic:Alkenes and Biology 142 3.22 Summary 143 3.23 Additional Problems 144
2.11 Drawing Isomers 82 2.12 Rings 83 2.13 Physical Properties of Alkanes and Cycloalkanes 86 2.14 Nuclear Magnetic Resonance Spectroscopy 88 2.15 Acids and Bases Revisited: More Chemical Reactions 90 2.16 Special Topic: Alkanes as Biomolecules 92 2.17 Summary 93 2.18 Additional Problems 94 3 Alkenes and Alkynes 97 3.1 Preview 98 3.2 Alkenes: Structure and Bonding 99 3.3 Derivatives and Isomers of Alkenes 107 3.4 Nomenclature 110 3.5 The Cahn–Ingold–Prelog Priority System 112 3.6 Relative Stability of Alkenes: Heats of Formation 115 3.7 Double Bonds in Rings 118 3.8 Physical Properties of Alkenes 123 3.9 Alkynes: Structure and Bonding 123 3.10 Relative Stability of Alkynes: Heats of Formation 126 3.11 Derivatives and Isomers of Alkynes 126 3.12 Triple Bonds in Rings 128 3.13 Physical Properties of Alkynes 129 3.14 Acidity of Alkynes 129 3.15 Molecular Formulas and Degrees of Unsaturation 130 3.16 An Introduction to Addition Reactions of Alkenes and Alkynes 131 3.17 Mechanism of the Addition of Hydrogen Halides to Alkenes 132 3.18 The Regiochemistry of the Addition Reaction 137 3.19 A Catalyzed Addition to Alkenes: Hydration 139 3.20 Synthesis: A Beginning 141 3.21 Special Topic: Alkenes and Biology 142 3.22 Summary 143 3.23 Additional Problems 144 viii CONTENTS
CONTENTS ix 4 Stereochemistry 147 4.1 Preview 148 4.2 Chirality 149 4.3 The (R/S)Convention 152 4.4 Properties of Enantiomers:Physical Differences 155 4.5 The Physical Basis of Optical Activity 157 4.6 Properties of Enantiomers:Chemical Differences 159 4.7 Interconversion of Enantiomers by Rotation about a Single Bond: gauche-Butane 163 4.8 Diastereomers and Molecules Containing More than One Stereogenic Atom 164 4.9 Physical Properties of Diastereomers:Resolution,a Method of Separating Enantiomers from Each Other 169 4.10 Determination of Absolute Configuration(R or S)172 4.11 Stereochemical Analysis of Ring Compounds(a Beginning)173 4.12 Summary of Isomerism 176 4.13 Special Topic:Chirality without"Four Different Groups Attached to One Carbon”177 4.14 Special Topic:Stereochemistry in the Real World:Thalidomide,the Consequences of Being Wrong-Handed 180 4.15 Summary 181 4.16 Additional Problems 182 5 Rings 185 5.1 Preview 186 5.2 Rings and Strain 187 5.3 Quantitative Evaluation of Strain Energy 193 5.4 Stereochemistry of Cyclohexane:Conformational Analysis 197 5.5 Monosubstituted Cyclohexanes 199 5.6 Disubstituted Ring Compounds 204 5.7 Bicyclic Compounds 211 5.8 Special Topic:Polycyclic Systems 216 5.9 Special Topic:Adamantanes in Materials and Biology 217 5.10 Summary 219 5.11 Additional Problems 220
4 Stereochemistry 147 4.1 Preview 148 4.2 Chirality 149 4.3 The (R/S) Convention 152 4.4 Properties of Enantiomers: Physical Differences 155 4.5 The Physical Basis of Optical Activity 157 4.6 Properties of Enantiomers: Chemical Differences 159 4.7 Interconversion of Enantiomers by Rotation about a Single Bond: gauche-Butane 163 4.8 Diastereomers and Molecules Containing More than One Stereogenic Atom 164 4.9 Physical Properties of Diastereomers: Resolution, a Method of Separating Enantiomers from Each Other 169 4.10 Determination of Absolute Configuration (R or S) 172 4.11 Stereochemical Analysis of Ring Compounds (a Beginning) 173 4.12 Summary of Isomerism 176 4.13 Special Topic: Chirality without “Four Different Groups Attached to One Carbon” 177 4.14 Special Topic: Stereochemistry in the Real World: Thalidomide, the Consequences of Being Wrong-Handed 180 4.15 Summary 181 4.16 Additional Problems 182 5 Rings 185 5.1 Preview 186 5.2 Rings and Strain 187 5.3 Quantitative Evaluation of Strain Energy 193 5.4 Stereochemistry of Cyclohexane: Conformational Analysis 197 5.5 Monosubstituted Cyclohexanes 199 5.6 Disubstituted Ring Compounds 204 5.7 Bicyclic Compounds 211 5.8 Special Topic: Polycyclic Systems 216 5.9 Special Topic: Adamantanes in Materials and Biology 217 5.10 Summary 219 5.11 Additional Problems 220 CONTENTS ix
CONTENTS 6 Alkyl Halides,Alcohols,Amines,Ethers, and Their Sulfur-Containing Relatives 223 6.1 Preview 224 6.2 Alkyl Halides:Nomenclature and Structure 225 6.3 Alkyl Halides as Sources of Organometallic Reagents: A Synthesis of Hydrocarbons 227 6.4 Alcohols 230 6.5 Solvents in Organic Chemistry 238 6.6 Diols(Glycols)240 6.7 Amines 240 6.8 Ethers 249 6.9 Special Topic:Thiols(Mercaptans)and Thioethers(Sulfides)251 6.10 Special Topic:Crown Ethers 254 6.11 Special Topic:Complex Nitrogen-Containing Biomolecules-Alkaloids 255 6.12 Summary 256 6.13 Additional Problems 258 7 Substitution and Elimination Reactions: The SN2,SNI,El,and E2 Reactions 261 7.1 Preview 262 7.2 Review of Lewis Acids and Bases 263 7.3 Reactions of Alkyl Halides:The Substitution Reaction 267 7.4 Substitution,Nucleophilic,Bimolecular:The SN2 Reaction 268 7.5 The SN2 Reaction in Biochemistry 288 7.6 Substitution,Nucleophilic,Unimolecular:The SN1 Reaction 289 7.7 Summary and Overview of the SN2 and SN1 Reactions 296 7.8 The Unimolecular Elimination Reaction:E1 298 7.9 The Bimolecular Elimination Reaction:E2 301 7.10 What Can We Do with These Reactions? How to Do Organic Synthesis 312 7.11 Summary 320 7.12 Additional Problems 323 8 Equilibria 331 8.1 Preview 332 8.2 Equilibrium 334
6 Alkyl Halides, Alcohols, Amines, Ethers, and Their Sulfur-Containing Relatives 223 6.1 Preview 224 6.2 Alkyl Halides: Nomenclature and Structure 225 6.3 Alkyl Halides as Sources of Organometallic Reagents: A Synthesis of Hydrocarbons 227 6.4 Alcohols 230 6.5 Solvents in Organic Chemistry 238 6.6 Diols (Glycols) 240 6.7 Amines 240 6.8 Ethers 249 6.9 Special Topic: Thiols (Mercaptans) and Thioethers (Sulfides) 251 6.10 Special Topic: Crown Ethers 254 6.11 Special Topic: Complex Nitrogen-Containing Biomolecules—Alkaloids 255 6.12 Summary 256 6.13 Additional Problems 258 7 Substitution and Elimination Reactions: The SN2, SN1, E1, and E2 Reactions 261 7.1 Preview 262 7.2 Review of Lewis Acids and Bases 263 7.3 Reactions of Alkyl Halides: The Substitution Reaction 267 7.4 Substitution, Nucleophilic, Bimolecular: The SN2 Reaction 268 7.5 The SN2 Reaction in Biochemistry 288 7.6 Substitution, Nucleophilic, Unimolecular: The SN1 Reaction 289 7.7 Summary and Overview of the SN2 and SN1 Reactions 296 7.8 The Unimolecular Elimination Reaction: E1 298 7.9 The Bimolecular Elimination Reaction: E2 301 7.10 What Can We Do with These Reactions? How to Do Organic Synthesis 312 7.11 Summary 320 7.12 Additional Problems 323 8 Equilibria 331 8.1 Preview 332 8.2 Equilibrium 334 x CONTENTS
CONTENTS xi 8.3 Entropy in Organic Reactions 337 8.4 Rates of Chemical Reactions 339 8.5 Rate Constant 341 8.6 Energy Barriers in Chemical Reactions: The Transition State and Activation Energy 342 8.7 Reaction Mechanism 349 8.8 The Hammond Postulate:Thermodynamics versus Kinetics 351 8.9 Special Topic:Enzymes and Reaction Rates 357 8.10 Summary 358 8.11 Additional Problems 360 9 Additions to Alkenes 1 363 9.1 Preview 364 9.2 Mechanism of the Addition of Hydrogen Halides to Alkenes 365 9.3 Effects of Resonance on Regiochemistry 366 9.4 Brief Review of Resonance 372 9.5 Resonance and the Stability of Carbocations 374 9.6 Inductive Effects on Addition Reactions 378 9.7 HX Addition Reactions:Hydration 380 9.8 Dimerization and Polymerization of Alkenes 384 9.9 Rearrangements during HX Addition to Alkenes 386 9.10 Hydroboration 390 9.11 Hydroboration in Synthesis:Alcohol Formation 398 9.12 Special Topic:Rearrangements in Biological Processes 401 9.13 Summary 402 9.14 Additional Problems 404 10 Additions to Alkenes 2 and Additions to Alkynes 409 10.1 Preview 410 10.2 Addition of H2 and X2 Reagents 410 10.3 Hydration through Mercury Compounds:Oxymercuration 421 10.4 Other Addition Reactions Involving Three-Membered Rings:Oxiranes and Cyclopropanes 423 10.5 Dipolar Addition Reactions:Ozonolysis and the Synthesis of Carbonyl(R2C=O)Compounds 436 10.6 Addition Reactions of Alkynes:HX Addition 444 10.7 Addition of X2 Reagents to Alkynes 447
8.3 Entropy in Organic Reactions 337 8.4 Rates of Chemical Reactions 339 8.5 Rate Constant 341 8.6 Energy Barriers in Chemical Reactions: The Transition State and Activation Energy 342 8.7 Reaction Mechanism 349 8.8 The Hammond Postulate: Thermodynamics versus Kinetics 351 8.9 Special Topic: Enzymes and Reaction Rates 357 8.10 Summary 358 8.11 Additional Problems 360 9 Additions to Alkenes 1 363 9.1 Preview 364 9.2 Mechanism of the Addition of Hydrogen Halides to Alkenes 365 9.3 Effects of Resonance on Regiochemistry 366 9.4 Brief Review of Resonance 372 9.5 Resonance and the Stability of Carbocations 374 9.6 Inductive Effects on Addition Reactions 378 9.7 HX Addition Reactions: Hydration 380 9.8 Dimerization and Polymerization of Alkenes 384 9.9 Rearrangements during HX Addition to Alkenes 386 9.10 Hydroboration 390 9.11 Hydroboration in Synthesis: Alcohol Formation 398 9.12 Special Topic: Rearrangements in Biological Processes 401 9.13 Summary 402 9.14 Additional Problems 404 10 Additions to Alkenes 2 and Additions to Alkynes 409 10.1 Preview 410 10.2 Addition of H2 and X2 Reagents 410 10.3 Hydration through Mercury Compounds: Oxymercuration 421 10.4 Other Addition Reactions Involving Three-Membered Rings: Oxiranes and Cyclopropanes 423 10.5 Dipolar Addition Reactions: Ozonolysis and the Synthesis of Carbonyl (R2C O) Compounds 436 10.6 Addition Reactions of Alkynes: HX Addition 444 10.7 Addition of X2 Reagents to Alkynes 447 P CONTENTS xi
xii CONTENTS 10.8 Hydration of Alkynes 448 10.9 Hydroboration of Alkynes 450 10.10 Hydrogenation of Alkynes:Alkene Synthesis through syn Hydrogenation 452 10.11 Reduction by Sodium in Ammonia:Alkene Synthesis through anti Hydrogenation 452 10.12 Special Topic:Three-Membered Rings in Biochemistry 455 10.13 Summary 456 10.14 Additional Problems 460 11 Radical Reactions 467 11.1 Preview 468 11.2 Formation and Simple Reactions of Radicals 469 11.3 Structure and Stability of Radicals 477 11.4 Radical Addition to Alkenes 481 11.5 Other Radical Addition Reactions 487 11.6 Radical-Initiated Addition of HBr to Alkynes 489 11.7 Photohalogenation 490 11.8 Allylic Halogenation:Synthetically Useful Reactions 497 11.9 Special Topic:Rearrangements(and Nonrearrangements) of Radicals 501 11.10 Special Topic:Radicals in Our Bodies;Do Free Radicals Age Us?504 11.11 Summary 505 11.12 Additional Problems 507 12 Dienes and the Allyl System:2p Orbitals in Conjugation 511 12.1 Preview 512 12.2 Allenes 513 12.3 Related Systems:Ketenes and Cumulenes 515 12.4 Allenes as Intermediates in the Isomerization of Alkynes 516 12.5 Conjugated Dienes 519 12.6 The Physical Consequences of Conjugation 521 12.7 Molecular Orbitals and Ultraviolet Spectroscopy 525 12.8 Polyenes and Vision 533 12.9 The Chemical Consequences of Conjugation: Addition Reactions of Conjugated Dienes 534 12.10 Thermodynamic and Kinetic Control of Addition Reactions 537
10.8 Hydration of Alkynes 448 10.9 Hydroboration of Alkynes 450 10.10 Hydrogenation of Alkynes: Alkene Synthesis through syn Hydrogenation 452 10.11 Reduction by Sodium in Ammonia: Alkene Synthesis through anti Hydrogenation 452 10.12 Special Topic: Three-Membered Rings in Biochemistry 455 10.13 Summary 456 10.14 Additional Problems 460 11 Radical Reactions 467 11.1 Preview 468 11.2 Formation and Simple Reactions of Radicals 469 11.3 Structure and Stability of Radicals 477 11.4 Radical Addition to Alkenes 481 11.5 Other Radical Addition Reactions 487 11.6 Radical-Initiated Addition of HBr to Alkynes 489 11.7 Photohalogenation 490 11.8 Allylic Halogenation: Synthetically Useful Reactions 497 11.9 Special Topic: Rearrangements (and Nonrearrangements) of Radicals 501 11.10 Special Topic: Radicals in Our Bodies; Do Free Radicals Age Us? 504 11.11 Summary 505 11.12 Additional Problems 507 12 Dienes and the Allyl System: 2pOrbitals in Conjugation 511 12.1 Preview 512 12.2 Allenes 513 12.3 Related Systems: Ketenes and Cumulenes 515 12.4 Allenes as Intermediates in the Isomerization of Alkynes 516 12.5 Conjugated Dienes 519 12.6 The Physical Consequences of Conjugation 521 12.7 Molecular Orbitals and Ultraviolet Spectroscopy 525 12.8 Polyenes and Vision 533 12.9 The Chemical Consequences of Conjugation: Addition Reactions of Conjugated Dienes 534 12.10 Thermodynamic and Kinetic Control of Addition Reactions 537 xii CONTENTS
CONTENTS xili 12.11 The Allyl System:Three Overlapping 2 Orbitals 541 12.12 The Diels-Alder Reaction of Conjugated Dienes 544 12.13 Special Topic:Biosynthesis of Terpenes 554 12.14 Special Topic:Steroid Biosynthesis 559 12.15 Summary 563 12.16 Additional Problems 564 13 Conjugation and Aromaticity 57 13.1 Preview 572 13.2 The Structure of Benzene 573 13.3 A Resonance Picture of Benzene 575 13.4 The Molecular Orbital Picture of Benzene 578 13.5 Quantitative Evaluations of Resonance Stabilization in Benzene 580 13.6 A Generalization of Aromaticity:Huickel's 4n+2 Rule 582 13.7 Substituted Benzenes 595 13.8 Physical Properties of Substituted Benzenes 598 13.9 Heterobenzenes and Other Heterocyclic Aromatic Compounds 598 13.10 Polynuclear Aromatic Compounds 602 13.11 Introduction to the Chemistry of Benzene 606 13.12 The Benzyl Group and Its Reactivity 610 13.13 Special Topic:The Bio-Downside,the Mechanism of Carcinogenesis by Polycyclic Aromatic Compounds 614 13.14 Summary 617 13.15 Additional Problems 619 14 Substitution Reactions of Aromatic Compounds 623 14.1 Preview 624 14.2 Hydrogenation of Aromatic Compounds 626 14.3 Diels-Alder Reactions 628 14.4 Substitution Reactions of Aromatic Compounds 631 14.5 Carbon-Carbon Bond Formation:Friedel-Crafts Alkylation 639 14.6 Friedel-Crafts Acylation 643 14.7 Synthetic Reactions We Can Do So Far 646 14.8 Electrophilic Aromatic Substitution of Heteroaromatic Compounds 652 14.9 Disubstituted Benzenes:Ortho,Meta,and Para Substitution 655 14.10 Inductive Effects in Aromatic Substitution 666
12.11 The Allyl System: Three Overlapping 2p Orbitals 541 12.12 The Diels–Alder Reaction of Conjugated Dienes 544 12.13 Special Topic: Biosynthesis of Terpenes 554 12.14 Special Topic: Steroid Biosynthesis 559 12.15 Summary 563 12.16 Additional Problems 564 13 Conjugation and Aromaticity 571 13.1 Preview 572 13.2 The Structure of Benzene 573 13.3 A Resonance Picture of Benzene 575 13.4 The Molecular Orbital Picture of Benzene 578 13.5 Quantitative Evaluations of Resonance Stabilization in Benzene 580 13.6 A Generalization of Aromaticity: Hückel’s 4n + 2 Rule 582 13.7 Substituted Benzenes 595 13.8 Physical Properties of Substituted Benzenes 598 13.9 Heterobenzenes and Other Heterocyclic Aromatic Compounds 598 13.10 Polynuclear Aromatic Compounds 602 13.11 Introduction to the Chemistry of Benzene 606 13.12 The Benzyl Group and Its Reactivity 610 13.13 Special Topic: The Bio-Downside, the Mechanism of Carcinogenesis by Polycyclic Aromatic Compounds 614 13.14 Summary 617 13.15 Additional Problems 619 14 Substitution Reactions of Aromatic Compounds 623 14.1 Preview 624 14.2 Hydrogenation of Aromatic Compounds 626 14.3 Diels–Alder Reactions 628 14.4 Substitution Reactions of Aromatic Compounds 631 14.5 Carbon–Carbon Bond Formation: Friedel–Crafts Alkylation 639 14.6 Friedel–Crafts Acylation 643 14.7 Synthetic Reactions We Can Do So Far 646 14.8 Electrophilic Aromatic Substitution of Heteroaromatic Compounds 652 14.9 Disubstituted Benzenes: Ortho, Meta, and Para Substitution 655 14.10 Inductive Effects in Aromatic Substitution 666 CONTENTS xiii
