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Heterocyclic Chemistry
Volume 3

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A Specialist Periodical Report

Heterocyclic Chemistry
Volume 3

A Review of the Literature Abstracted
between July 1980 and June 1981

Senior Reporters
H. Suschitzky and 0. Meth-Cohn Department of Chemistry and
Applied Chemistry, University of Salford
Reporters

G. V. Boyd Chelsea College, London
G. M. Brooke University of Durham
S. D. Carter Queen Elizabeth College, London
G. W. H. Cheeseman Queen Elizabeth College, London
J. de Mendoza lnstituto de Quimica Medica, Madrid

J. Elguero fnstituto de Quimica Medica, Madrid
G. P. Ellis UWIST, Cardiff
S. Gronowitz University of Lund, Sweden
T. V. Lee Brunel University, Middlesex
J. R. Malpass University of Leicester
T. J. Mason Lanchester Polytechnic, Coventry
J. T. Sharp University of Edinburgh

The Royal Society of Chemistry
Burlington House, London W I V OBN

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British Library Cataloguing in Publication Data
Heterocyclic chemistry.-Vol. 3.-(Specialist periodical report/
Royal Society of Chemistry)
1. Heterocyclic compounds - Periodicals
I. Royal Society of Chemistry
547l.58’05
QD339

ISBN 0-85186-823-1
ISSN 0144-8773

Copyright @ 1982
The Royal Society of Chemistry

All Rights Reserved
No part of this book may be reproduced or transmitted in any form

or by any means - graphic, electronic, including photocopying, recording,
taping, or information storage and retrieval systems - without
written permission from The Royal Society of Chemistry

Set in Times on Linotron and printed offset by
J. W. Arrowsmith Ltd., Bristol, England
Madein Great Britain

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Introduction

Volume 3 of ‘Heterocyclic Chemistry’ covers literature based essentially on
Volumes 93 and 94 (i.e. July 1980-June 1981) of Chemical Abstracts. The
arrangement of the Chapters and the extensive ‘Table of Contents’ remain the
same as for the previous two volumes, which will facilitate search and back
reference. Increasing economic pressure demanded great selectivity from our
authors, some of whom, we realize, would have preferred to give more coverage
to certain aspects. As editors we are, however, entirely satisfied that our contributors have shown themselves masters in constraint. Another concession to
economy is the omission of an author index, which was felt by the majority of
our authors, and of those of our readers who were consulted, not to be essential
to the purpose of the Report. Judging from the critical reviews and many
unsolicited statements by readers, this series is proving a valuable resource for
industrial and academic chemists, by virtue of its unrivalled position amongst
annual reports.
The Society and the editors are constantly striving to reduce production costs
to a level which will make acquisition of the report for one’s personal collection
feasible.
Our thanks go to all authors for supplying manuscripts on schedule for early

publication, and to the editorial staff of the Royal Society of Chemistry for their
help.
H. SUSCHITZKY& 0. METH-COHN

V

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Contents
Chapter 1 Three-Membered Ring Systems
By T. J. Mason
1 Reviews 1
General 1
Rings containing Oxygen 1
Rings containing Nitrogen 2
2 Oxirans 2
Preparation 2
Catalytic Oxidation of Alkenes, using Oxygen or
Oxygen-containing Gases 2
Oxidation of Alkenes by Peroxy-acids 4
Oxidation of Alkenes, using Peroxides 5
Halohydrin Cyclizations and Related Reactions 7
Synthesis via Attack of a Carbanion on the Carbonyl
Group of Aldehydes and Ketones 8
The Synthesis of Chiral Oxirans 10
The Synthesis and Reactivities of Aromatic Oxides 13

Miscellaneous Syntheses 14
Spectra and Theoretical Chemistry 17
Reactions with Electrophiles 19
Ring-opening 19
Cyclization 20
Nucleophilic Ring-opening Reactions 21
With Oxygen and Nitrogen Nucleophiles 21
With Carbanions 23
Reduction and Elimination Reactions 24
Thermal and Photochemical Reactions 25
Reactions with Organometallic Compounds 28
Miscellaneous Reactions 30
3 Oxirens 30
4 Aziridines 31

Preparation 3 1
By Direct Insertion 31
By Cyclization 32
uia Ring-Contraction 33
vii

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1


viii

Heterocyclic Chemistry
Chiral Aziridines 33

Reactions 33
Thermal 33
Ring-opening to Acyclic Compounds 34
Formation of Other Ring Systems 35

5 Azirines 36
Preparation 36
Reactions 37

6 Thiirans 40
Preparation 40
Reactions 41
Chemistry of Thiiranium Ions 42
7 Thiirens 43
8 Diaziridines 44
9 Diazirines 44
10 Oxaziridines 46

11 Other Ring Systems 47
Chapter 2 Four-Membered Ring Systems
By T. V. Lee

49

1 Highlights and Reviews 49

2 Systems containing One Nitrogen Atom 49
Azetidines and Azetines 49
Azetidinones 50
3 Systems containing Two Nitrogen Atoms or One Nitrogen

and a Second Heteroatom 55

4 Systems containing Oxygen 56
Oxetans 56
Dioxetans 59
5 Systems containing Sulphur 59

6 Miscellaneous Four-Membered Rings 6 1

Chapter 3 Five-Membered Ring Systems

63

By G. V. Boyd, J. de Mendoza, J. Elguero, and S. Gronowitz
Part I Thiophens and their Selenium and Tellurium Analogues
By S. Gronowitz

1 General 63

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63


ix

Contents

2 Monocyclic Thiophens 63
Synthesis by Ring-Closure Reactions 63

Synthesis from Other Rings 66
Physical Properties 68
Theoretical Calculations 68
Photoelectron and Ultraviolet Spectra 68
Nuclear Magnetic Resonance 69
Miscellaneous 69
Electrophilic Substitution Reactions 70
Nucleophilic and Radicaloid Substitution Reactions 72
Organometallic Derivatives 73
Photochemistry 76
Desulphurization and Hydrogenation of Simple Thiophens 77
The Structures and Reactions of Hydroxy-, Mercapto-, and
Amino-thiophens 79
Reactivities of Side-Chains 82
Reactions of Thiophen Aldehydes and Ketones 83
Reactions of Carboxythiophen and its Derivatives 85
Reactions of Vinylthiophens and Related Compounds 86
Reactions at Benzylic Positions 87
Various Reactions in the Side-Chain 88
Reaction at Sulphur: Thiophen Dioxides 90
Di- and Tetra-hydrothiophens 91
Bi- and Poly-heterocycles 92
Naturally Occurring Thiophens 93
Thiophen Analogues of Steroids 93
Thiophens of Pharmacological Interest 94
Polymers from Thiophens 95
3 Benzothiophens and their Benzo-fused Systems 96
Benzo[b Jthiophens 96
Synthesis 96
Physical Properties 97

Substitution Reactions 97
Reactions of the Side-Chain 98
Benzo[b]thiophen S-Oxides 99
Benzo[c]thiophens 100
Dibenzothiophens 100
Pharmacologically Active Compounds 100

4 Thiophen Analogues of Polycyclic Aromatic Hydrocarbons 101
Analogues of Anthracene and Phenanthrene 101
Various Carbocycle-Fused Systems 101
5 Thiophen Fused to Five-Membered Heteroaromatic Rings
Isothiazole-Fused and Related Systems 103

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Heterocyclic Chemistry

X

6 Thiophen Fused to Six-Membered Heteroaromatic Rings
Thiophen Analogues of Quinoline 104
Thiophen Analogues of Isoquinoline 105
Pyrimidine-Fused Systems 105
Miscellaneous Fused Systems 106

104


7 Selenophens and Tellurophens 108
Monocyclic Selenophens 108
Condensed Selenophens 109
Tellurophens 110

Part I I Systems containing Nitrogen and Sulphur, Selenium,
or Tel I uriu m
By J. Elguero and J. de Mendoza

1 Introduction and Reviews

111

2 Isothiazoles 111
Synthesis 111
From ‘Thiacyanocarbons’ (Type A; C-C-C-N + S) 111
From Nitrile N-Sulphides (Type B; C-C + S-N-C) 111
From Thioenaminones (Type C; S-C-C-C-N)
112
Physical Properties 112
Chemical Properties 113
Alkylation 113
Cycloaddition 113
Other Reactions 113
3 1,2-Benzisothiazoles, their 1-Oxides, and their 1,l-Dioxides 113
Synthesis 113
Chemical Properties 114

4 1,2-Benzisoselenazole and 1,2-Benzisotellurazole 114
5 2,l-Benzisothiazoles 115


6 Other Condensed Ring Systems incorporating Isothiazole 115
Thieno-[2,3-d]-, -[3,2-d]-, and -[2,3-c]-isothiazoles 115
Thieno-[2,3-d]-, - [3,2-d]-, and -[4,3-d]- isoselenazoles, and
Selenopheno[3,2-d]isoselenazoles 116
[ l]Benzothien0[2,3-d]isothiazoles 1 16
Isothiazolo[5,4-b]pyridine 116
1,4-Dithiino[c]isothiazole, 1,4-Dithiino[2,3-c ; 6,5-c’]diisothiazole, and Isothiazolo[3,4-f][ 1,2,3,4,5]pentathiepin 1 16
Benzo[c]bisisothiazole and Benzo[c]trisisothiazole 117
Isothiazolo-[3,4-e]-and -[4,3-e]-[2,1,3]benzothiadiazoles 117

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Contents

Naphtho[2,1-d]isothiazoles 117
Isothiazolonaphthoquinones and Bis(isothiazo1o)benzoquinones 118
7 Thiazoles 118
Synthesis 118
Hantzsch’s Synthesis (Type A; S-C-N + C-C)
118
Type G (N-C-S-C-C)
Type H (S-C + C-N-C) 118
Type K (S-C-N-C-C)
119
Physical Properties 119
Chemical Properties 119

Reactions of 2-Aminothiazoles 120
Reactions of Thiazolium Salts 120
Reactions of Meso-ionic Thiazoles 121
Miscellaneous Reactions 121

118

8 A’-Thiazolines 121
Synthesis 121
Type A (S-C-N + C-C) 121
Type D (C-N + S-C-C) 121
122
Type K (S-C-N-C-C)
Physical Properties 122
Chemical Properties 122
9 A3-Thiazolines 122

10 A4-Thiazolines 123
Synthesis 123
Type A (S-C-N + C-C) 123
Type B (S-C + C-C-N) 123
Type E (S-C-C-N + C) 123
123
Type G (N-C-S-C-C)
Miscellaneous Methods 123
Chemical Properties 124
11 Thiazolidines 124
Synthesis 124
Type A (S-C-N + C-C) 124
Type D (C-N + C-C-S)

124
Type E (N-C-C-S + C) 125
Type K (S-C-N-C-C)
125
Physical Properties 125
Chemical Properties 126
Rhodanines, Isorhodanines, and Thiorhodanines 126
12 Selenazoles 127
13 Benzothiazoles 127
Synthesis 127

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Heterocyclic Chemistry

xii

From o-Amino-benzenethiols (Type A; S-C6H4-N
Type €3 (C&-N-C-S)
127
Type c (N-C6H4-S-C) 128
Type D (S-C6H4-N-C) 128
128
Type G (C6&-S-C-N)
Physical Properties 128
Chemical Properties 129
Substitution Reactions 129
Addition Reactions 130
Alkylation 130

Ring-Cleavage Reactions 130
Rearrangements 130

+ C)

127

14 Condensed Ring Systems incorporating Thiazole or
Selenazole 131
Structures comprising Two Five-Membered Rings ( 5 3 ) 131
Thiazolo-[2,3-c]- and -[3,2-b]- [1,2,4]triazoles
[C,N,-C,NS]
131
Imidazo-[2,l-b]-, - [3,2-c]-, and -[5,l-b]- thiazoles
[C,NS-C,N,] 131
Pyrrolo-[1,2-c]-, -[2,1-b]-, and -[3,2-c]-thiazoles
[C,NS-C,N] 132
Thieno[3,2-d]- thiazoles and -selenazoles and Selenopheno[3,2-d]thiazoles [C,NS-C4S] 132
Structures comprising one Five-Membered and One SixMembered Ring (5,6) 132
Thiazolo[3,2-a]pyrimidines [C,NS-C4N2] 132
Thiazolo-[3,2-a]- and -[3,4-a]-pyrazines [C3NS-C4N2] 133
Thiazolo[3,2-~]pyridines[C,NS-C,N] 133
Thiazolo[3,4-~]pyridines[C3NS-C5N] 133
Thiazolo[4,5-b]thiopyran [C3NS-C5S] 133
Structures comprising One Five-Membered and One SevenMembered Ring (5,7) 134
Thiazolo[4,3-~]thiazepine[C3NS-C5NS] 134
Thiazolo[S,4-c]azepines [C3NS-C6N] 134
Structures comprising Two Five-Membered Rings and One SixMembered Ring (5,5,6) 134
1,2,4-Triazolo[3,4 -b]benzothiazoles [C2N3-C3NS-C6] 134
Thiazolo[4,5-g]benzoxazoles [C3NS-C3NO-C6] 134

Thiazolo[2,3-b]benzothiazoles[C3NS-C3NS-C6] 134
Imidazo[2,3-d]thiazolo-[2,3-b]and-[3,2-a]-pyrimidines
[C3NS-C,N,-C4N2] 135
Thiazolo[3,2-a]benzimidazoles [c3Ns-c3N2-c6] 135
Thiazolo[3,4-a]benzimidazoles [C3NS-C3N2-C6] 135
Imidazo[2,l-b]benzothiazoles[C3NS-C3N,-C6] 135
Thiazolo[3,2-a Ithieno[2,3-d]p yrimidines [C,NS-C4S-C4N,] 136

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xiii

Contents

Structures comprising One Five-Membered Ring and Two SixMembered Rings (5,6,6) 136
Pyrimido[2,1-b]benzothiazoles [C3NS-C4N2-C6] 136
Thiazolo-[2,3-b]-, - [3,2-a ]-, and -[3,2-c ]- quinazolines
[C3NS-C4N2-C6] 136
Thiazolo[4,5-b]quinoxalines [C3NS-C4N2-C6] 137
Thiazino[2,3- b lbenzothiazole [C,NS -C4NS-C6] 137
Pyrido-[2,3-d] - and -[3,241- thiazolo[3',2'-a Jpyridines
[C,NS-C5N-CSN] 137
Pyrido[2,1-b]benzothiazoles[C3NS-C5N-C6] 137
Thiazolo[3,2-a]quinolines [C3NS-C5N-C6] 138
Thiazolo[2,3-a ]isoquinolines [C3NS-C5N-C6] 138
Naphtho[ 2,3-d]thiazoles [C,NS-C6-C6] 138
Structures comprising Two Five-Membered and Two SixMembered Rings (5,5,6,6) 138
Other Condensed Systems incorporating Thiazole 139


15 Thiadiazoles and Selenadiazoles 139
1,2,3-Thiadiazoles 139
Synthesis 139
Physical Properties 140
Chemical Properties 140
1,2,3-Benzothiadiazoles 140
1,2,3-Selenadiazoles 141
1,2,4-Thiadiazoles 141
Synthesis 141
Physical Properties 142
Chemical Properties 143
1,3,4-Thiadiazoles 143
Synthesis 143
Physical Properties 144
Chemical Properties 144
Condensed 1,3,4-Thiadiazoles 145
1,3,4-Selenadiazoles 146
1,2,5-Thiadiazolesand 1,2,5-Selenadiazoles 146
Synthesis 146
Chemical Properties 146
1,2,3-Benzothiadiazoles 147
Synthesis 147
Physical Properties 147
Chemical Properties 147
Condensed 1,2,5-Thiadiazoles 147
2,1,3-Benzoselenadiazoles 148
14 Dithiazoles and Diselenazoles 148

1,2,3-Dithiazoles 148
1,2,4-DithiazoIes 148


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xiv

Heterocyclic Chemistry
1,3,2-Benzodithiazoles 149
1,4,2-Dithiazoles 149

17 Oxathiazoles and Selenathiazoles 149
1,3,4-Oxathiazoles 149
18 Miscellaneous Ring Systems 150
1,2,3,4-Thiatriazoles 150
1,2,3,5-Thiatriazoles 150
1,2,3,5-Dithiadiazoles 150
1,3,2,4-Dithiadiazoles 150
1,2,4,3,5-Trithiadiazoles 150

Part 111 Other Five-Membered Ring Systems
ByG. V. Boyd

151

1 Introduction 151

2 Reviews

151


3 Systems with One Heteroatom, and their Benzo-analogues
Furans 152
Formation 152
Reactions 154
Benzofurans and Other Annelated Furans 158
Pyrroles 162
Formation 162
Reactions 166
Indoles 171
Formation 171
Reactions 173
Isoindoles 177
Other Systems 178
4 Systems containing Two Identical Heteroatoms 179
Dioxoles 179
Dithioles and Related Systems 180
Tetrathiafulvalenes and Related Compounds 183
Pyrazoles 184
Formation 184
Reactions 185
Indazoles 188
Imidazoles 189
Formation 189
Reactions 190
Benzimidazoles and Other Annelated Imidazoles 193

5 Systems containing Two Different Heteroatoms 195
Oxathioles and Thiaselenoles 195

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Contents

xv
Isoxazoles 196
Formation 196
Reactions 198
Benzisoxazoles 201
Oxazoles 203
Formation 203
Reactions 204
Benzoxazoles and a Thiasilapentane System 208

6 Systems containing Three Identical Heteroatoms 209
1,2,3-Triazoles and Annelated 1,2,3-Triazoles 209
1,2,4-Triazoles and a 1,2,4-TrithioIe 2 11
7 Other Systems containing Three Heteroatoms 214
Oxadiazoles 2 14
1,2,3- and 1,2,4-Oxadiazoles 214
1,2,5-Oxadiazoles 214
1,3,4-Oxadiazoles 215
Phosphorus Compounds 216
Miscellaneous Other Systems 218
8 Systems containing Four Heteroatoms 2 19

Tetrazoles 2 19
Other Systems 219

9 Compounds containing Two Fused Five-Membered
Rings (53) 220
Hypervalent Sulphur Compounds 220
Nitrogen Systems 220
Monoaza-Compounds 220
Diaza-Compounds 22 1
Triaza-Compounds 222
Other Systems 223
10 Compounds containing Fused Five- and
Six-Membered Rings (5,6) 224
Nitrogen Systems 224
Monoaza-Compounds 224
Diaza-Compounds 225
Triaza-Compounds 226
Tetra-aza-Compounds 228
Penta-aza-Compounds 229
Mixed Oxygen-Nitrogen Systems 23 1

11 Compounds containing Fused Five- and Seven-Membered
Rings (5,7)and Three or Four Fused Heterocyclic Rings
[(5,5,5),(5,5,6),(5,5,7),(5,6,6),(5,6,8), and (5397,711 233

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Heterocyclic Chemistry

xvi

Chapter 4 Six-Membered Ring Systems


237

By S. D. Carter, G, W. H. Cheeseman, and G. P. N i i s

237

Part I Systems containing Nitrogen
By S. D. Carter and G. W. H. Cheeseman

1 Introduction 237
2 Reviews 237
3 Azines and their Hydro- and Benzo-derivatives 238
Pyridines 238
Synthesis 238
Properties 242
Reduced Pyridines 250
Quinoline, Isoquinoline, and their Benzo- and Hydroderivatives 253
4 Diazines and their Reduced and Fused Derivatives 261

1,2-Diazines 261
1,3-Diazines 263
1,4-Diazines 27 1
5 Triazines and Tetrazines 275

6 Fused Systems containing One Five- and One SixMembered Ring (5,6) 278
7 Fused Systems containing Two Six-Membered Rings (6,6) 281

8 Oxazines, Thiazines, and their Fused Derivatives 284
Oxazines 284

Thiazines 287
9 Other Oxygen- and Sulphur-containing Systems 289
Classified Reference List 291
Part II Six-Membered Rings containing Oxygen or Sulphur
By G. P. Ellis

1 Books and Reviews 293
2 Heterocycles containing One Oxygen Atom

Reduced Pyrans 293
Pyrans and Pyrylium Salts 294
Reduced Pyrones 295
2-Pyrones 296
4-Pyrones 297
Chromans 297
Isochromans and Isochromenes 298
Chromenes 298
Chromanones 299
Chromones 300

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xvii

Contents

Flavans 301
Flavanones and Isoflavanones 302
Flavones 302
Isoflavones 303
Dihydroisocoumarins 304
Coumarins 305
Isocoumarins 307
Xanthenes and Xanthones 308

3 Heterocycles containing One Sulphur Atom 308
Thiopyrans 308
Isothiochromans, Thiochromenes, and Isothiochromenes 3 10
Thiocoumarins and Isothiocoumarins 3 10
Thioxanthenes and Thioxanthones 3 11

4 Heterocycles containing One Oxygen and One Sulphur
Atom 311
5 Heterocycles containing Two Oxygen Atoms 3 12
1,3-Dioxans 3 12
1,4-Dioxans 3 13

6 Heterocycles containing Two Sulphur Atoms 314
1,3-Dithians 314
1,4-Dithians 315
7 Heterocycles containing an Oxygen or Sulphur Atom
in each of Two or Three Rings 3 16

Chapter 5 Seven-Membered Ring Systems
By J. T. Sharp
1 Introduction 319

2 Reviews 319
3 Azepines, Diazepines, and Triazepines 3 19
Didehydro-intermediates 319
Monocyclic Azepines 321
Formation 321
Reactions 323
Fused Azepines 324
Formation 324
1-Bemazepines 324
2-Benzazepines 326
3-Benzazepines 326
Hetero-fused azepines 327
Reactions 328
1,2-Diazepines 329
Formation 329
Reactions 332

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Heterocyclic Chemistry

xviii
1,3-Diazepines 333
1,4-Diazepines 334
Formation 334
Reactions 336
Triazepines 337


4 Oxepins and Dioxepins 337
Oxepins 337
Formation '337
Reactions 340
Dioxepins 340

5 Thiepins and Dithiepins 341
6 Systems containing Two Different Heteroatoms 34 1
Oxazepines 341
Thiazepines 342

7 Other Systems 343

Chapter 6 Eight-Membered and Larger Ring Systems
By G.M. Brooke
1 Eight-Membered Rings 345
Rings containing One Heteroatom 345
Rings containing Two Heteroatoms 346
Rings containing Six Heteroatoms 347
2 Nine- and Ten-Membered Heterocycles 347
3 Macrocycles 350
Systems containing Nitrogen as the only Heteroatom 350
One Nitrogen Atom 350
Four Nitrogen Atoms 351
Six or More Nitrogen Atoms 352
Systems containing Heteroatoms other than Nitrogen 353
Crown Ethers and Related Compounds 356
Synthesis 356
Effects on Chemical Reactions 357

Reactions of the Macrocyclic Rings 359
Formation of Host-Guest Complexes 360

Chapter 7 Bridged Systems
By J. R. Malpass

1 Reviews 367
2 Physical Methods 367
X-Ray and Electron Diffraction 367
Photoelectron Spectroscopy 368

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xix

Contents
Nuclear Magnetic Resonance Spectroscopy 369
Miscellaneous Methods 370

3 Nitrogen-containing Compounds 37 1
Synthesis 371
Cycloadditions 371
Other Cyclizations 374
Reactions 375
Bridged Annulenes, Cyclazines, and Propellanes
Bridged Azoalkanes 378


376

4 Oxygen-containing Compounds 379
Synthesis 379
Cycloadditions 379
Miscellaneous Methods 382
Bridged Peroxides 384
5 Systems that contain Other Heteroatoms 385

Errata for Volume 2

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387


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1
Three-Membered Ring Systems
BY T. J. MASON

1 Reviews
General.-Recent
advances in the synthesis of three-membered-ring
heterocycles have been reviewed,' as have the stability and chemistry of the
unsatilrated systems oxiren and thiiren together with either azirine2 or
~ilacyclopropane.~
Rings containing Oxygen.-The industrial importance of the oxirans is reflected

by the inclusion of two sections in the latest edition of the Kirk-Othmer
Encyclopedia of Chemical Technology concerning ethylene oxide4 and perduoroepoxides.' The manufacture of ethylene oxide has also been the subject of three
consecutive articles in Catalysis
General preparative techniques that have been surveyed include synthetic
and mechanistic aspects of metal-catalysed epoxidation with hydroperoxides,'
new epoxidation reagents," and new methods for stereo-controlled epoxidation."
Articles on specific classes of epoxy-compounds have appeared, dealing with
allene oxide (vinyloxiran),'2 cyclic poly-epoxides (mainly five-, six-, seven-, and
eight-membered systems),13 long-chain epoxy-acid~,'~and steroid epoxides
(their analytical and biological ~ignificance).'~
H. Quast, Heterocycles, 1980,14, 1677.
M. Torres, E. M. Lown, H. E. Gunning, and 0. P. Strausz, Pure Appl. Chem., 1980,52, 1623.
Y. Oshiro, M. Komatsu, and T. Agawa, Kagaku No Ryoiki, Zokan, 1980, 1 (Chem. Abstr., 1980
93,220 5 11).
J. N. Cawse. J. P. Henry, M. W. Swartzlander, and P. H. Wadia, in 'Kirk-Othmer Encyclopedia
of Chemical Technology', ed. M. Grayson and D. Eckroth, Wiley, New York, 1980,3rd edn., Vol.
9, p. 432.
P. R. Resnick, in 'Kirk-Othmer Encyclopedia of Chemical Technology', ed. M. Grayson and D.
Eckroth, Wiley, New York. 1980, 3rd edn., Vol. 10, p. 956.
W. M. H. Sachtler, C. Backx, and R. A. Van Santen, Catal. Rev.-Sci. Eng., 1981,23,127.
' J. V. Porcelli, Caral. Rev.-Sci. Eng., 1981, 23, 151.
* J. C. Zomerdijk and M. W. Hall, Catal. Rev.-Sci. Eng., 1981, 23, 163.
R. A. Sheldon, J. Mol. Catal., 1980, 7, 107.
lo J. Rebek, Jr., Heterocycles, 1981,15, 517.
l 1 H. Kotsuki and I. Saito, Yuki Gosei Kagaku Kyokai Shi, 1980,38, 936 (Chem. Abstr., 1981,94,
174 740).
l2 T. H. Chan and B. S . Ong, Tetrahedron, 1980,36,2269.
l 3 W. Adam and M. Balci, Tetrahedron, 1980,36,833.
l4 F. D. Gunstone, in 'Fatty Acids', ed. E. H. Pryde, AOCS, Champagne, Ill., 1979, p. 379.
H. Breuer, J. Clin. Chem. Clin. Biochem., 1980,18,937.


''

1

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2

Heterocyclic Chemistry

Rings containing Nitrogen.-Aziridine chemistry has been included in a review
of cyclic imines.I6 Reviews on azirines include their reactions with transition
metals,” their use as synthons for other heterocycles,18and the preparations of
cyclophanes involving azirine rings.”
2 Oxirans

Preparation.-Catalytic Oxidation of Alkenes to Oxirans, using Oxygen or Oxy gen-containing Gases. It is possible to catalyse the epoxidation of ethene, using
simply powdered silver as a suspension in acetic anhydride.20 Using a mixed
ethene :oxygen :nitrogen feed of 82 :4 : 15 parts, under pressure, and at 180 “C,
90% conversion of oxygen is achieved in 10 minutes.
It has been found that silver carrier catalysts that incorporate a number of
combinations of alkali metals (one of which must be caesium) have greater
efficiencies for the preparation of ethylene oxide than any such catalyst containing
only a single alkali
A study of the stereochemistry of the epoxidation
of cis-l,2-dideuterioetheneon various silver catalysts, under differing reaction
conditions, revealed equilibrations of the deuterium atoms in the product ranging
from 57 to 99’/0.~~

A possible explanation for this is based upon the extent of
oxidation of the catalyst surface under the particular reaction conditions.
The role of the catalyst support in the oxidation of ethene has been investigated
by using alumina (a-A1203)that is doped with either GeOz or MgO, making it
either an n-type or p-type semiconductor, re~pectively.~~
Compared with silver
catalysts on undoped supports, p-type carriers show enhanced reactivity and
selectivity whereas n-type have the opposite effect.
Styrene has been epoxidized in the liquid phase, using titanium carbide and
b ~ r i d e It. ~appears
~
that, during the reaction, an oxygen-containing polymeric
film is formed on the catalyst surface which increases its activity but also increases
the induction period for the reaction. The latter may be eliminated by the
addition of dibenzyl peroxide.
Azibenzil (PhCOCPhN2) reacts readily with O2in the presence of transitionmetal-ion catalysts to give an intermediate (probably a metal-carbene-oxygen
complex) which can transfer oxygen to alkenes and yield epoxides under very
mild c ~ n d i t i o n sThe
. ~ ~ reactions are performed at room temperature in CH2C12
that contains azibenzil, Pd(OAc)*, and alkene, with oxygen being simply bubbled
through the solution during the reaction. Yields of epoxides up to 87% have
been reported, together with benzil, which is the by-product of the reaction.
16

l7

l8
l9
2o


”

G. E. Ham, in ‘Kirk-Othmer Encyclopedia of Chemical Technology’, ed. M. Grayson and D.
Eckroth, Wiley, New York, 1980, 3rd edn., Vol. 13, p. 142.
T. Sakakibara. Kagoshima Daigaku Rika Hokoku, 1980, 87 (Chem. Abstr., 1981, 94, 174 743).
A. Hassner, Heterocycles, 1980, 14, 1517.
Y. Sakata, Yuki Gosei Kagaku Kyokai Shi, 1980,38, 164 (Chem. Abstr., 1980,93, 167 990).
N. Hiroyuki, Y. Kobayashi, A. Baba, and K. Murayama, Jpn. Kokai Tokkyo Koho 80 15427
(Chem. Abstr., 1980, 93, 150 108).
M. M. Bhasin, P. G. Ellgen, and C. B. Hendrix, Ger. Offen. 3 010533 (Chem. Absrr., 1981, 94,
83 916).

22
23
24

25

M. Egashira, R. L. Kuczkowski, and N. W. Cant, J. Catal., 1980,65,297.
X . E. Verykios, F. P. Stein, and R. W. Coughlin, J. Catal., 1980,66, 147.
S. Yu. Zasedatelev, Yu. M. Shul’ga, E. A. Blyumberg, and Yu. G. Borod’ko Dokl. Akad. Nauk
SSSR, 1980,252, 1170 (Chem. Abstr., 1980,93,238 341).
H. S. Ryang and C. S. Foote, J. A m . Chem. Soc., 1980,102,2129.

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Three-Membered Ring Systems

3


The conversion of cyclic alkenes into epoxy-alcohols may be achieved by
using oxygen and the [ V O ( ~ C ~ C ) ~ ] - A Icatalyst
B N system.26With dichloroethane
as solvent, the yields of epoxy-alcohol (2) and epoxide (3) that were obtained
from cyclopentene (1; n = 1) were 41 and 28% respectively (Scheme 1); for
cyclohexene (1; n = 2), 10 and 40% were produced, whereas cycloheptene
(1; n = 3) gave only the epoxide (3; n = 3) (99O/t).

Reagents: i, [VO(acac),], AIBN, CH,ClCH,Cl, 0,

Scheme 1

Paquette et al., in an ongoing study of electronic control of stereoselectivity,
have investigated the direction of addition of singlet oxygen to 1,4-dimethoxynaphthalene derivatives in which bridged bicyclic systems are fused across C-2
and C-3 (Scheme 2).27 Using Rose Bengal as the sensitizer, photochemical
oxidation of (4; n = 1) gave mainly the endo-epoxide ( 5 ) (77%) together with
7% of em-epoxide (6), whereas for (4; n = 2) the main product was em-epoxide
(6) (77%), with only 13% of ( 5 ) . Each of these epoxidatioris is the reverse of
the stereochemistry that is obtained by using alkaline hydroperoxide as the
oxidant. While the direction of epoxidation with hydroperoxide can be rationalized in terms of standard steric and kinetic control factors, the direction of
photochemical epoxidation is thought to arise from the effect of u-electrons
from the bicyclic systems influencing the 7r-orbitals of the aromatic part of the

a--(7)

?Ac
I

(14)

Reagents: i, 02,hv, Rose Bengal; ;i, hydrolysis of naphthoquinone monoketal; iii, 0,, hv, biacetal;
iv, O,, hv, tetraphenylporphyrin; v, 0,, hv, hematoporphyrin.HC1; vi, exo-(13), hv,
hernatoporphyrin, argon

Scheme 2

26

”

K. Kaneda, K. Jitsukawa, T. Itoh, and S. Teranishi, J. Org. Chem., 1980,45, 3004.
L. A. Paquette, F. Bellarny, M. C. Boehm, and R. Gleiter, J. Org. Chem., 1980 45,4913.

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