Advanced Organic Chemistry: Part A: Structure and Mechanisms

737 Pages·1984·59.8 MB·English

Advanced Organic
• t SECOND
Che m IS ry EDITION
Part A: Structure and Mechanisms
Advanced Organic Chemistry
PART A: Structure and Mechanisms
PART B: Reactions and Synthesis
Advanced Organic
SECOND
Chemistry EDITION
Part A: Structure ,and Mechanisms
FRANCIS A. CAREY
and RICHARD J. SUNDBERG
University of Virginia
Charlottesville, Virginia
SPRINGER SCIENCE+BUSINESS MEDIA, LLC
Library of Congress Cataloging in Publication Data
Carey, Francis A., 1937-
Advanced organic chemistry.
Includes bibliographical references and index.
Contents: pt. A. Structure and mechanisms-pt. B. Reactions and synthesis.
I. Chemistry, Organic. I. Sundberg, Richard J., 1938- . II. Title.
QD251.2.C36 1984 547 84-8229
ISBN 978-1-4757-1145-5 ISBN 978-1-4757-1143-1 (eBook)
DOI 10.1007/978-1-4757-1143-1
© 1984 Springer Science+B usiness Media New York
Originally published by Plenum Press, New York in 1984
All rights reserved
No part of this book may be reproduced, stored in a retrieval system, or transmitted,
in any form or by any means, electronic, mechanical, photocopying, microfilming,
recording, or otherwise, without written permission from the Publisher
Preface to the Second Edition
The purpose of this edition is the same as that of the first edition, that is, to provide
a deeper understanding of the structures of organic compounds and the mechanisms
of organic reactions. The level is aimed at advanced undergraduates and beginning
graduate students. Our goal is to solidify the student's understanding of basic
concepts provided in an introduction to organic chemistry and to fill in much more
information and detail, including quantitative information, than can be presented
in the first course in organic chemistry.
The first three chapters consider the fundamental topics of bonding theory,
stereochemistry, and conformation. Chapter 4 discusses the techniques that are used
to study and characterize reaction mechanisms. The remaining chapters consider
basic reaction types with a broad coverage of substituent effects and stereochemistry
being provided so that each reaction can be described in good, if not entirely
complete, detail.
The organization is very similar to the first edition with only a relative shift in
emphasis having been made. The major change is the more general application of
qualitative molecular orbital theory in presenting the structural basis of substituent
and stereoelectronic effects. The primary research literature now uses molecular
orbital approaches very widely, while resonance theory serves as the primary tool
for explanation of structural and substituent effects at the introductory level. Our
intention is to illustrate the use of both types of interpretation, with the goal of
facilitating the student's ability to understand and apply the molecular orbital
concepts now widely in use.
As in the first edition, the specific reactions discussed have been chosen to
illustrate a point and no effort has been made to trace the origin of a particular
explanation or observation. Thus references to a particular example do not imply
any indication of priority. We have also tried to cite references to reviews which
will give readers the opportunity to consider specific reactions from a much more
comprehensive and detailed point of view than is possible in this text.
v
Vl Some of the problems are new. The general level is similar to that in the first
edition and it is expected that most of the problems will present a considerable
PREFACE
degree of challenge to the typical student, since most represent application of the
ideas presented in the text to different systems and circumstances, rather than review
or repetition of the material which was explicitly presented in the text. References
to the literature material upon which the problems are based are given at the end
of the book for nearly all the problems.
The companion volume, Part B, has also been substantially revised to reflect
the major developments in synthetic procedures that have taken place since the
initial material was prepared. Part B extends the material of Part A with particular
emphasis on the synthetic application of organic reactions. We believe that the
material in Parts A and B can serve to prepare students to assimilate and apply the
extensive primary and review literature of organic chemistry.
We thank colleagues who have provided comments and encouragement regard-
ing the first edition. We hope that we will continue to receive suggestions concerning
the organization and presentation of the material and also information concerning
errors and omissions.
F. A. Carey
R. J. Sundberg
Charlottesville, Virginia
January 1983
Contents of Part A
Chapter 1. Chemical Bonding and Molecular Structure 1
1.1. Valence Bond Approach to Chemical Bonding 2
1.2. Bond Energies, Lengths, and Dipoles . . . . 11
1.3. Molecular Orbital Methods . . . . . . . . 17
1.4. Qualitative Application of Molecular Orbital Theory 23
1.5. Hiickel Molecular Orbital Theory . . . . . . . . 37
1.6. PMO Theory . . . . . . . . . . . . . . . . 44
1. 7. Interaction between 1T and u Systems-Hyperconjugation 51
General References 55
Problems .... 55
Chapter 2. Stereochemical Principles 61
2.1. Enantiomeric Relationships 62
2.2. Diastereomeric Relationships 69
2.3. Dynamic Stereochemistry 76
2.4. Prochiral Relationships 85
General References 91
Problems .... 92
Chapter 3. Conformational, Steric, and Stereoelectronic Effects 99
3.1. Steric Strain and Molecular Mechanics 100
3.2. Conformations of Acyclic Molecules 107
3.3. Conformations of Cyclohexane Derivatives 111
3.4. Carbocyclic Rings Other Than Six Membered 123
3.5. Conformational Analysis of Heterocyclic Molecules 128
3.6. Molecular Orbital Methods Applied to Conformational Analysis 133
Vll
vm 3. 7. Conformational Effects on Reactivity . .. . . . . . . . . 137
3.8. Angle Strain and Its Effect on Reactivity . . . . . . . . 141
CONTENTS OF
PART A 3.9. Relationships between Ring Size and Facility of Ring Closure 147
3.1 0. Torsional Strain and Related Stereoelectronic Effects 150
General References 154
Problems . . . . 154
Chapter 4. Study and Description of Organic Reaction Mechanisms 161
4.1. Thermodynamic Data 161
4.2. Kinetic Data . . . . . . . . . . . . . . . . . . . . 165
4.3. Substituent Effects and Linear Free-Energy Relationships 179
4.4. Isotope Effects 190
4.5. Characterization of Reaction Intermediates 194
4.6. Catalysis . . . . . . . . . . . 197
4. 7. Solvent Effects . . . . . . . . . 202
4.8. Structural Effects in the Gas Phase 209
4.9. Basic Mechanistic Concepts: Kinetic Versus Thermodynamic Control,
Hammond's Postulate, the Curtin-Hammett Principle 212
4.10. Isotopes in Labeling Experiments 220
4.11. Stereochemistry 221
General References 223
Problems . . . . 224
Chapter 5. Nucleophilic Substitution 235
5.1. The Limiting Cases-Substitution by the Ionization (SN 1) Mechanism 238
5.2. The Limiting Cases-Substitution by the Direct Displacement (SN2)
Mechanism 240
5.3. Detailed Mechanistic Descriptions and Borderline Mechanisms 243
5.4. Carbonium Ions . . . . . . . . 248
5.5. Nucleophilicity and Solvent Effects 263
5.6. Leaving-Group Effects . . . . . 271
5. 7. Steric and Other Substituent Effects on Substitution and Ionization
Rates . . . . . . . . . . . . . . . . . . . . . . . . . 274
5.8. Stereochemistry of Nucleophilic Substitution . . . . . . . . 278
5.9. Secondary Kinetic Isotope Effects in Substitution Mechanisms 287
5.10. Neighboring-Group Participation 289
5.11. Carbonium Ion Rearrangements 298
5.12. The Norbornyl Cation 304
General References 312
Problems . . . . 313
Chapter 6. Polar Addition and Elimination Reactions 323 lX
CONTENTS OF
6.1. Addition of Hydrogen Halides to Alkenes ...... . 324 PART A
6.2. Acid-Catalyzed Hydration and Related Addition Reactions 330
6.3. Addition of Halogens . . . . 333
6.4. Additions Involving Metal Ions . . 339
6.5. Additions to Acetylenes . . . . . 341
6.6. The E2, E1, and E1cb Mechanisms 345
6. 7. Orientation Effects in Elimination Reactions 351
6.8. Stereochemistry of E2 Elimination Reactions 356
6.9. Dehydration of Alcohols . . .... 361
6.10. Eliminations Not Involving C-H Bonds 362
General References 365
Problems .... 366
Chapter 7. Carbanions and Other Nucleophilic Carbon Species 0 •• 0 373
7 .1. Acidity of Hydrocarbons . . . . . . . . 373
7.2. Carbanions Stabilized by Functional Groups 382
7.3. Enols and Enamines 390
General References 395
Problems .... 396
Chapter 8. Reactions of Carbonyl Compounds . . . . . . . . . . 403
8.1. Hydration and Addition of Alcohols to Aldehydes and Ketones 404
8.2. Addition-Elimination Reactions of Ketones and Aldehydes 411
8.3. Reactivity of Carbonyl Compounds toward Addition 417
8.4. Ester Hydrolysis 421
8.5. Aminolysis of Esters 426
8.6. Amide Hydrolysis 431
8. 7. Acylation of Nucleophilic Oxygen and Nitrogen Groups 433
8.8. Intramolecular Catalysis 437
General References 444
Problems . . . . 444
Chapter 9. Aromaticity and Electrophilic Aromatic Substitution 0 ••• 455
9.1. Aromaticity . . . . . . . . . . 455
9 .1.1. The Concept of Aromaticity 455
9.1.2. The Annulenes ..... 460
9.1.3. Aromaticity in Charged Rings 468
9.1.4. Homoaromaticity 472
9.1.5. Fused-Ring Systems 475