Ernest Beaux, the perfumer who created Chanel No. 5, said, "One has to rely on chemists to find new aroma chemicals creating new, original notes. In perfumery, the future lies primarily in the hands of chemists." This book provides chemists and chemists-to-be with everything they need to know in order to create welcome new fragrances for the world to enjoy. It offers a simplified introduction into organic chemistry, including separation techniques and analytical methodologies; discusses the structure of perfume creation with respect to the many reactive ingredients in consumer products; and shows how to formulate effective and long-lasting scents.
Fundamentals of Fragrance Chemistry starts by covering the structure of matter in order to show how its building blocks are held together. It continues with chapters that look at hydrocarbons and heteroatoms. A description of the three states of matter and how each can be converted into another is offered next, followed by coverage of separation and purification of materials. Other chapters examine acid/base reactions; oxidation and reduction reactions; perfume structure; the mechanism of olfaction; natural and synthetic fragrance ingredients; and much more.
-Concentrates on aspects of organic chemistry, which are of particular importance to the fragrance industry
-Offers non-chemists a simplified yet complete introduction to organic chemistry?from separation techniques and analytical methodologies to the structure of perfume creation
-Provides innovative perfumers with a framework to formulate stable fragrances from the myriad of active ingredients available
-Looks at future trends in the industry and addresses concerns about sustainability and quality management
Fundamentals of Fragrance Chemistry is an ideal resource for students who are new to the subject, as well as for chemists and perfumers already working in this fragrant field of science.
Table of Contents
Preface xi
Introduction xiii
1 The Structure of Matter 1
The Route to the Atomic Theory 1
The Atomic Theory, Atomic Number, and Atomic Weight 4
Atomic Structure 7
Isotopes 8
The Electronic Structure of Atoms 9
Electronic Structure of Transition Metals 11
Hybridisation of Orbitals 11
Chemical Bonding, Ions, Cations, Anions, and Molecules 12
Review Questions 16
2 Carbon 1 - Hydrocarbons 17
Ethane: Conformational Isomers 17
Alkanes: Structural Isomers 20
Alkenes: Geometric Isomers 22
Alkynes 26
Cyclic Structures 26
Polycyclic Structures 28
Greek Letters 30
Aromatic Rings 31
Stereoisomerism 33
Rules for Hydrocarbon Nomenclature 36
Quick Rules for Isomers 37
Stereoisomers 37
Review Questions 38
3 Carbon 2 - Heteroatoms 39
Hydrogen Bonding 39
Alcohols 40
Phenols 43
Ethers 44
Aldehydes 45
Ketones 46
Carboxylic Acids 47
Esters 49
Acid Anhydrides and Chlorides 50
Acetals and Ketals 50
Peroxy Compounds 52
Nitrogen-Amines and Ammonium Salts 53
Nitrogen-Imines, Schiff’s Bases, and Enamines 54
Nitrogen-Amides/Peptides 55
Nitrogen-Nitriles 56
Nitrogen-Nitro Compounds 57
Sulfur 58
Heterocyclic Compounds 60
Review Question 66
4 States of Matter 67
Solids 67
Liquids 71
Gases 71
Phase Changes 71
Two‐Phase Systems 73
Solubility 74
Surfactants 75
Emulsions 79
Micelles 81
Detergency 81
Bilayers 82
Colloids 84
Review Questions 84
5 Separation and Purification 85
Distillation 85
Sublimation 93
Crystallisation 93
Solvent Extraction 94
Recent Developments in Commercial Extraction of Natural Fragrance
Ingredients 95
Chromatography 96
Paper Chromatography 98
Thin Layer Chromatography 98
Column Chromatography 99
High Performance Liquid Chromatography 100
Gas Chromatography 100
Review Questions 105
6 Analysis 107
Physical Methods of Analysis 108
Density 108
Melting Point 108
Boiling Point 108
Refractive Index 109
Optical Rotation 109
Flashpoint 109
Viscosity 109
Colour 109
Chemical Methods of Analysis 110
Titration 110
Acid Content 111
Base Content 111
Peroxide Content 111
Ester Value 111
Aldehyde/Ketone Content 112
Phenol Content 112
Chemical Oxygen Demand (COD) 112
Water Content 112
Atomic Absorption 113
Spectroscopic Methods of Analysis 113
Ultraviolet (UV) 114
Infrared (IR) 118
Nuclear Magnetic Resonance (NMR) 120
Mass Spectrometry (MS) 124
Gas Chromatography-Mass Spectrometry (GC-MS) 127
Eugenol as an Example of Spectroscopic Techniques 127
Quality Control 131
Review Questions 132
7 Chemical Reactivity 133
The Three Laws of Thermodynamics 133
Free Energy 135
Chemical Reactions 136
The Principle of Microscopic Reversibility and Chemical Equilibrium 137
Reaction Profiles 138
Catalysts 140
Types of Organic Reactions 140
Review Questions 145
8 Chemistry and Perfume 1: Acid/Base Reactions 147
Acids and Bases 147
Strong and Weak 149
pH 150
Electrophiles and Nucleophiles 152
Esterification and Ester Hydrolysis 154
The Aldol Reaction and Aldol Condensation 155
Acetals and Ketals 158
Schiff’s Bases and Enamines 160
Nitriles 161
Alcohol Dehydration 162
Acid‐Catalysed Addition to Olefins 163
The Michael Reaction 164
The Grignard Reaction 165
The Friedel-Crafts Reaction 167
Electrophilic Substitutions in Aromatic Molecules 168
Review Questions 170
9 Oxidation and Reduction Reactions 171
Review Questions 185
10 Perfume Structure 187
Notes, Chords, and Discords 187
Ingredients 187
Odour Families and Top, Middle, and Base Notes 188
Persistence/Tenacity 191
Threshold 192
Impact 192
Radiance/Bloom 193
Physical and Chemical Factors 194
Review Questions 196
11 Chemistry in Consumer Goods 197
Introduction 197
Acids in Consumer Goods 198
Bases in Consumer Goods 199
Nucleophiles in Consumer Goods 200
Oxidants in Consumer Goods 201
Reductants in Consumer Goods 202
Surfactants in Consumer Goods 204
Chelating Agents in Consumer Goods 205
Photoactive Agents in Consumer Goods 206
Antibacterial Agents in Consumer Goods 207
Other Reactive Ingredients in Consumer Goods 208
Types of Consumer Goods 209
Fine Fragrance 209
Cosmetics and Toiletries 210
Personal Wash 210
Laundry 211
Household 212
Review Questions 214
12 The Chemistry of Living Organisms 215
Molecular Recognition 215
Classes of Natural Chemicals 218
Carbohydrates 218
Nucleic Acids 221
Lipids 223
Proteins 225
Toxicity and Product Safety 230
Review Questions 239
13 The Mechanism of Olfaction 243
The Role of Olfaction in Biology 243
The Organs Used in Olfaction 244
The Process of Olfaction 246
Transport to the Receptors 246
The Receptor Event 247
The Combinatorial Nature of Olfaction 249
The Perception of Odour 252
Review Questions 256
14 Natural Fragrance Ingredients 257
Why Does Nature Produce Odorous Chemicals? 257
Basic Principles of Biosynthesis: Enzymes and Cofactors 258
General Pattern of Biosynthesis of Secondary Metabolites 261
Polyketide Biosynthesis 262
Lipid Biosynthesis 263
The Shikimic Acid Pathway 265
Terpenoids 267
Degradation Products 277
Malodours 279
Review Questions 281
15 Synthetic Fragrance Ingredients 283
Why the Industry Uses Synthetic Fragrance Ingredients? 283
The Economics of Fragrance Ingredient Manufacture 284
Production of Fragrance Ingredients from Polyketides and Shikimates 288
Terpenoid Production 290
Production of Fragrance Ingredients from Petrochemicals 302
What Is Required of a Fragrance Ingredient? 320
How Novel Fragrance Ingredients Are Designed? 322
Review Questions 326
16 Chemical Information 329
How New Chemical Information Is Generated and Published? 329
Patents 329
Reviews and Books 331
Abstracts 331
How to Find Chemical Information? 333
17 Towards a Sustainable Future 335
What Is Sustainability? 335
Commercial Feasibility 337
Safety in Use 337
Natural Fragrance Ingredients 340
Synthetic Fragrance Ingredients 341
Synthetic Fragrance Ingredients A: Use of By‐Products 341
Synthetic Fragrance Ingredients B: Environmental Impact 342
Synthetic Fragrance Ingredients C: Biotechnology 344
Synthetic Fragrance Ingredients D: Finding the Balance 345
The Symrise Route 347
The Takasago Route 347
The BASF Route 348
Menthol Sustainability 349
Pro‐fragrances 351
Social and Health Factors 353
Understanding Olfaction 353
Malodour Management 354
Health and Well‐Being 355
Information 356
Conclusion 356
Answers to Review Questions 357
Glossary 371
Bibliography 379
Index 381
