New Trends in Green Chemistry

278 Pages·2004·6.33 MB·English

by  V. K. Ahluwalia

New Trends in
GREEN CHEMISTRY
New Trends in
GREEN CHEMISTRY
V. K. Ahluwalia
Visiting Professor
Dr. B. R. Ambedkar Centre for Biomedical Research
University ofD elhi. Delhi -J1 0007. India
M.Kidwai
Coordinator
International Chapter ofG reen Chemistry in India
Department ofC hemistry. University ofD elhi.
Delhi -llO 007. India
.
. ,
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Kluwer Academic Publishers
BOSTON DORDRECHT LONDON
Anamaya Publishers
NEW DELHI
A C/.P. catalogue record for the book is available from the Library ofC ongress
ISBN 978-94-015-7102-9 ISBN 978-1-4020-3175-5 (eBook)
DOI 10.1007/978-1-4020-3175-5
Copublished by Kluwer Academic Publishers,
P.O. Box 17,3300 AA Dordrecht, The Netherlands
with Anamaya Publishers, New Delhi, India
Sold and distributed in all the countries, except India, by
Kluwer Academic Publishers, 101 Philip Drive,
Norwell, MA 02061, U.S.A. and in Europe by
Kluwer Academic Publishers, P.O. Box 322,
3300 AH Dordrecht, The Netherlands
In India by Anamaya Publishers
F-230, Lado Sarai, New Delhi - 110 030, India
All rights reserved.
Copyright © 2004. Anamaya Publishers, New Delhi, India
Softcover reprint of the hardcover 1s t edition 2004
No part of the material protected by this copyright notice may be reproduced or
utilized in any form or by any means, electronic or mechanical, including
photocopying, recording or by any information storage and retrieval system,
without the written permission from the copyright owner.
To
Professor Sukhdev, FNA
on his 80th birthday
Foreword
Organic chemistry has played a vital role in the development of diverse
molecules which are used in medicines, agrochemicals and polymers. Most
ofthe chemicals are produced on an industrial scale. The industrial houses
adopt a synthesis for a particular molecule which should be cost-effective.
No attention is paid to avoid the release of harmful chemicals in the
atmosphere, land and sea. During the past decade special emphasis has
been made towards green synthesis which circumvents the above problems.
Prof. V. K. Ahluwalia and Dr. M. Kidwai have made a sincere effort in this
direction.
This book discusses the basic principles of green chemistry incorporating
the use of green reagents, green catalysts, phase transfer catalysis, green
synthesis using microwaves, ultrasound and biocatalysis in detail. Special
emphasis is given to liquid phase reactions and organic synthesis in the solid
phase.
I must congratulate both the authors for their pioneering efforts to
write this book. Careful selection of various topics in the book will serve
the rightful purpose for the chemistry community and the industrial houses
at all levels.
PROF. JAVED IQBAL, PhD, FNA
Distinguished Research Scientist & Head
Discovery Research
Dr. Reddy's Laboratories Ltd.
Miyapur, Hyderabad -500 050, India
Preface
Organic chemistry dealS' with the synthesis of molecules having diverse
uses in medicines, agio chemicals and biomolecules. The industries producing
such chemicals are basically concerned with the type of reaction involved,
the percentage yield etc. so that synthesis becomes cost effective. Special
attention is given to ensure that there is no environmental pollution. All
these form the basis of Green Chemistry-the pressing need of all nations.
This book discusses designing green synthesis, basic principles of green
chemistry with its role in day-to-day life, environmental pollution, green
reagents and catalysts, phase transfer catalysis in green synthesis, microwave
induced green synthesis, ultrasound assisted green synthesis, biocatalysts in
organic synthesis, aqueous phase reactions, organic synthesis in the solid
state, versatile ionic liquids as green solvents and finally some examples of
synthesis involving basic principles of green chemistry.
We are grateful to Dr. Dennis Hjersen, Director, Green Chemistry
Institute, USA; Professor Sukhdev, FNA, INSA Professor, New Delhi;
Professor Nityanand, FNA, Former Director, CDR! Lucknow; Prof. Harjeet
Singh, FNA, Professor Emeritus, Guru Nank Dev University, Amritsar;
Prof. Mihir K. Chaudhury, FNA, Head, Department of Chemistry, Indian
Institute of Technology, Guwahati; Prof. S. Chandrasekharan, FNA, Head,
Department of Chemistry, Indian Institute of Science (Bangalore);
Professor Javed Iqbal, FNA, Distinguished Research Scientist and Head,
Discovery Research, Dr. Reddy's Laboratories Ltd., Hyderabad, for their
valuable discussions.
V. K. AHLUWALIA
M. KJDWAI
Contents
Foreword vii
Preface ix
1. Introduction 1
2. Designing a Green Synthesis 2
2.1 Choice of Starting Materials 2
2.2 Choice of Reagents 2
2.3 Choice of Catalysts 2
2.4 Choice of Solvents 3
3. Basic Principles of Green Chemistry 5
3.1 Prevention of Waste/By-Products 5
3.2 Maximum Incorporation of the Reactants (Starting
Materials and Reagents) into the Final Product 6
3.2.1 Rearrangement Reactions 6
3.2.2 Addition Reactions 7
3.2.3 Substitution Reactions 7
3.2.4 Elimination Reactions 8
3.3 Prevention or Minimization of Hazardous Products 8
3.4 Designing Safer Chemicals 9
3.5 Energy Requirements for Synthesis 9
3.6 Selection of Appropriate Solvent 9
3.7 Selection of Starting Materials 10
3.8 Use of Protecting Groups 10
3.9 Use of Catalyst 11
3.10 Products Designed Should be Biodegradable 12
3.11 Designing of Manufacturing Plants l3
3.12 Strengthening of Analytical Techniques 14
4. Green Chemistry in Day-to-Day Life 15
4.1 Dry Cleaning of Clothes 15
4.2 Versatile Bleaching Agent 15
xii Contents
5. Environmental Pollution 17
6. Green Reagent 21
6.1 Dimethylcarbonate 21
6.2 Polymer Supported Reagents 22
6.2.1 Polymer SupportedPeracids 22
6.2.2 Polymer Supported Chromic Acid 22
6.2.3 Polymeric Thioanisolyl Resin 22
6.2.4 Poly-N-Bromosuccinimide (PNBS) 22
6.2.5 Polymeric Organotin Dihydride Reagent as a Reducing Agent 24
6.2.6 Polystyrene Carbodiimide 24
6.2.7 Polystyrene Anhydride 24
6.2.8 Sulfonazide Polymer 24
6.2.9 Polystyrene Wittig Reagent 25
6.2.10 Polymeric Phenylthiomethyl Lithium Reagent 25
6.2.11 Polymer Supported Peptide Coupling Agent 26
7. Green Catalysts 27
7.1 Acid Catalysts 27
7.2 Oxidation Catalysts 29
7.3 Basic Catalysts 30
7.4 Polymer Supported Catalysts 31
7.4.1 Polystyrene-aluminium Chloride 32
7.4.2 Polymeric Super Acid Catalysts 32
7.4.3 Polystyrene-metalloporphyrins 32
7.4.4 Polymer Supported Photosensitizers 33
7.4.5 Polymer Supported Phase Transfer Catalysts 33
7.4.6 Miscellaneous Illustrations 34
Ti0 Photocatalyst in Green Chemistry 34
2
Solid Support Reagents 34
Synthesis of Bromo organics: Development of
Newer and Ecofriendly Sromination Protocols
and Brominating Agents 35
Synthesis ofPyridinium Fluorochromate (PFC) 35
Synthesis of Isooctane 36
8. Phase Transfer Catalysis in Green Synthesis 39
8.1 Introduction 39
'8.2 Applications ofPTC in Organic Synthesis 41
8.2.1Nitriles from Alkyl or Acyl Halides 41
8.2.2 Alkyl FluQrides from Alkyl Halides 42
8.2.3 Generation ofDihalocarbenes 42
8.2.4 Generation ofVinylidene Carbenes 44
8.2.5 Elimination Reactions 44
Contents xiii
8.2.6 C-Alkylations 45
C-Alkylation of Activated Nitriles 45
C-Alkylation of Activated Ketones 46
C-Alkylation of Aldehydes 46
8.2.7 N-Alkylations 46
N-Alkylation of Aziridines 46
N-Alkylation of P--Lactams 46
8.2.8 S-Alkylation 47
8.2.9 Darzen's Reaction 47
8.2.10 Williamson's Ether Synthesis 48
8.2.11 The Wittig Reaction 48
8.2.12 Sulphur Ylides 48
8.2.13 Heterocyclic Compounds 49
3-Alkyl Coumarins 49
Flavones 49
3-Aryl-2H-l,4-Benzoxazines 50
8.3 Oxidation Using Hydrogen Peroxide Under PTC Condition 50
8.4 Crown Ethers 51
8.4.1 Esterification 51
8.4.2 Saponification 51
8.4.3 Anhydride Fonnation 52
8.4.4 PotassiumPennanganate Oxidation 52
8.4.5 Aromatic Substitution Reaction 53
8.4.6 Elimination Reaction 54
8.4.7 Displacement Reaction 54
8.4.8 Generation ofC arb ene 54
8.4.9 SuperoxideAnionReaction 55
8.4.10 Alkylation 56
9. Microwave Induced Green Synthesis 59
9.1 Introduction S9
9.2 Applications 60
9.2.1 Microwave Assisted Reactions in Water 61
Hofinann Elimination 61
Hydrolysis 61
Oxidation of Toluene 62
Oxidation of Alcohols 62
Hydrolysis of Methyl benzoate to Benzoic Acid (Saponification) 63
9.2.2 Microwave Assisted Reactions in Organic Solvents 64
Esterification: Reaction of Carboxylic Acid and Alcohol 64
Esterification: Reaction of Carboxylic Acids and
Benzyl Ethers Using LnBr) (Ln = La, Nd, Sm, Dy, Er) 64
Fries Rearrangement 64
Orthoester Claisen Rearrangement 65
Diels Alder Reaction 65
Synthesis of Chalcones 65
Decarboxylation 66
xiv Contents
9.2.3 Microwave Solvent Free Reactions (Solid State Reactions) 66
Deacetylation 67
Deprotection 67
Saponification of Esters 68
Alkylation of Reactive Methylene Compounds 68
Condensation of Active Methylene Compounds with Aldehydes 68
Synthesis of Nitriles from Aldehydes 68
Synthesis of Anhydrides from Dicarboxylic Acid 69
Reductions 70
Synthesis of Heterocyclic Compounds 71
9.3 Conclusion 71
10. Ultrasound Assisted Green Synthesis 73
10.1 Introduction 73
10.2 Applications of Ultrasound 74
10.2.1 Esterification 74
10.2.2 Saponification 74
10.2.3 Hydrolysis 74
10.2.4 Substitution Reactions 75
10.2.5 Addition Reactions 76
10.2.6 Alkylations 77
10.2.7 Oxidation 78
10.2.8 Reduction 78
10.2.9 Hydroboration 80
10.2.10 Coupling Reactions 81
10.2.11 Fridel-Crafts Reaction 82
10.2.12 Diels-Alder Reaction 82
10.2.13 Sinunons-SmithReaction 82
10.2.14 BouveaultReaction 83
10.2.15 CannizaroReaction 84
10.2.16 Strecker Synthesis 84
10.2.17 Reformatsky Reaction 84
10.2.18 Conversion of Ketones into Tertiary Alcohols 85
10.2.19 SynthesisofChromenes 86
10.3 Conclusion 86
11. Biocatalysts in Organic Synthesis 88
11.1 Introduction 88
11.2 Biochemical (Microbial) Oxidations 90
11.3 Biochemical (Microbial) Reductions 99
11.4 Enzymes Catalysed Hydrolytic Processes 102
11.4.1 Enantioselective Hydrolysis of Meso Diesters 102
11.4.2 Hydrolysis ofN-acylarnino Acids 103
11.4.3 Miscellaneous Applications of Enzymes 104