Cover
Preface
Introduction
1 The Structure of Matter
1. The Route to the Atomic Theory
2. The Atomic Theory, Atomic Number, and Atomic Weight
3. Atomic Structure
4. Isotopes
5. The Electronic Structure of Atoms
6. Electronic Structure of Transition Metals
7. Hybridisation of Orbitals
8. Chemical Bonding, Ions, Cations, Anions, and Molecules
2 Carbon1 – Hydrocarbons
1. Ethane: Conformational Isomers
2. Alkanes: Structural Isomers
3. Alkenes: Geometric Isomers
4. Alkynes
5. Cyclic Structures
6. Polycyclic Structures
7. Greek Letters
8. Aromatic Rings
9. Stereoisomerism
10. Rules for Hydrocarbon Nomenclature
11. Quick Rules for Isomers
12. Stereoisomers
3 Carbon 2 – Heteroatoms
1. Hydrogen Bonding
2. Alcohols
3. Phenols
4. Ethers
5. Aldehydes
6. Ketones
7. Carboxylic Acids
8. Esters
9. Acid Anhydrides and Chlorides
10. Acetals and Ketals
11. Peroxy Compounds
12. Nitrogen–Amines and Ammonium Salts
13. Nitrogen–Imines, Schiff's Bases, and Enamines
14. Nitrogen–Amides/Peptides
15. Nitrogen–Nitriles
16. Nitrogen–Nitro Compounds
17. Sulfur
18. Heterocyclic Compounds
4 States of Matter
1. Solids
2. Liquids
3. Gases
4. Phase Changes
5. Two‐Phase Systems
6. Solubility
7. Surfactants
8. Emulsions
9. Micelles
10. Detergency
11. Bilayers
12. Colloids
5 Separation and Purification
1. Distillation
2. Sublimation
3. Crystallisation
4. Solvent Extraction
5. Recent Developments in Commercial Extraction of Natural Fragrance Ingredients
6. Chromatography
7. Paper Chromatography
8. Thin Layer Chromatography
9. Column Chromatography
10. High Performance Liquid Chromatography
11. Gas Chromatography
6 Analysis
1. Physical Methods of Analysis
2. Chemical Methods of Analysis
3. Spectroscopic Methods of Analysis
4. Gas Chromatography–Mass Spectrometry (GC–MS)
7 Chemical Reactivity
1. The Three Laws of Thermodynamics
2. Free Energy
3. Chemical Reactions
4. The Principle of Microscopic Reversibility and Chemical Equilibrium
5. Reaction Profiles
6. Catalysts
7. Types of Organic Reactions
8 Chemistry and Perfume 1: Acid/Base Reactions
1. Acids and Bases
2. Electrophiles and Nucleophiles
3. Esterification and Ester Hydrolysis
4. The Aldol Reaction and Aldol Condensation
5. Acetals and Ketals
6. Schiff's Bases and Enamines
7. Nitriles
8. Alcohol Dehydration
9. Acid‐Catalysed Addition to Olefins
10. The Michael Reaction
11. The Grignard Reaction
12. The Friedel–Crafts Reaction
13. Electrophilic Substitutions in Aromatic Molecules
9 Oxidation and Reduction Reactions
10 Perfume Structure
1. Notes, Chords, and Discords
2. Ingredients
3. Odour Families and Top, Middle, and Base Notes
4. Persistence/Tenacity
5. Threshold
6. Impact
7. Radiance/Bloom
8. Physical and Chemical Factors
11 Chemistry in Consumer Goods
1. Introduction
2. Acids in Consumer Goods
3. Bases in Consumer Goods
4. Nucleophiles in Consumer Goods
5. Oxidants in Consumer Goods
6. Reductants in Consumer Goods
7. Surfactants in Consumer Goods
8. Chelating Agents in Consumer Goods
9. Photoactive Agents in Consumer Goods
10. Antibacterial Agents in Consumer Goods
11. Other Reactive Ingredients in Consumer Goods
12. Types of Consumer Goods
13. Fine Fragrance
14. Cosmetics and Toiletries
15. Personal Wash
16. Laundry
17. Household
12 The Chemistry of Living Organisms
1. Molecular Recognition
2. Classes of Natural Chemicals
3. Carbohydrates
4. Nucleic Acids
5. Lipids
6. Proteins
7. Toxicity and Product Safety
13 The Mechanism of Olfaction
1. The Role of Olfaction in Biology
2. The Organs Used in Olfaction
3. The Process of Olfaction
14 Natural Fragrance Ingredients
1. Why Does Nature Produce Odorous Chemicals?
2. Basic Principles of Biosynthesis: Enzymes and Cofactors
3. General Pattern of Biosynthesis of Secondary Metabolites
4. Polyketide Biosynthesis
5. Lipid Biosynthesis
6. The Shikimic Acid Pathway
7. Terpenoids
8. Degradation Products
9. Malodours
15 Synthetic Fragrance Ingredients
1. Why the Industry Uses Synthetic Fragrance Ingredients?
2. The Economics of Fragrance Ingredient Manufacture
3. Production of Fragrance Ingredients from Polyketides and Shikimates
4. Terpenoid Production
5. Production of Fragrance Ingredients from Petrochemicals
6. What Is Required of a Fragrance Ingredient?
7. How Novel Fragrance Ingredients Are Designed?
16 Chemical Information
1. How New Chemical Information Is Generated and Published?
2. How to Find Chemical Information?
17 Towards a Sustainable Future
1. What Is Sustainability?
2. Natural Fragrance Ingredients
3. Synthetic Fragrance Ingredients
4. Pro‐fragrances
5. Social and Health Factors
6. Information
7. Conclusion
Answers to Review Questions
1. Chapter 1
2. Chapter 2
3. Chapter 3
4. Chapter 4
5. Chapter 5
6. Chapter 6
7. Chapter 7
8. Chapter 8
9. Chapter 9
10. Chapter 10
11. Chapter 11
12. Chapter 12
13. Chapter 13
14. Chapter 14
15. Chapter 15
Glossary
Bibliography
1. Books
2. Journal Articles
Index
End User License Agreement

List of Illustrations

Chapter 1
1. Figure 1.1 The periodic table of the elements.
2. Figure 1.2 Shapes of orbitals.
3. Figure 1.3 The electronic configurations of the first 10 elements.
4. Figure 1.4 Carbon atoms with hybridised orbitals.
5. Figure 1.5 Formation of an ionic bond between sodium and chlorine.
6. Figure 1.6 A fragment of the sodium chloride crystal lattice.
7. Figure 1.7 Formation of a covalent bond between two hydrogen atoms.
8. Figure 1.8 Formation of covalent bonds in methane.
9. Figure 1.9 Structural formulae of methane.
Chapter 2
1. Figure 2.1 Formation of a hydrogen molecule.
2. Figure 2.2 Conformations of ethane.
3. Figure 2.3 The isomeric butanes.
4. Figure 2.4 n‐Pentane.
5. Figure 2.5 Formation of a C–C double bond.
6. Figure 2.6 Isomeric butenes.
7. Figure 2.7 An olefin found in galbanum and shapes of long chains.
8. Figure 2.8 Formation of a C–C triple bond.
9. Figure 2.9 Internal angles of regular polygons.
10. Figure 2.10 Conformations of cyclohexane.
11. Figure 2.11 Representations of benzene.
12. Figure 2.12 Structures of the xylenes.
13. Figure 2.13 Numbering systems for naphthalene.
14. Figure 2.14 Non‐superimposability of asymmetric carbon atoms.
15. Figure 2.15 Representations of the enantiomers of limonene.
16. Figure 2.16 Determining (R)‐ and (S)‐nomenclature.
Chapter 3
1. Figure 3.1 Representations of methanol.
2. Figure 3.2 Hydrogen bonding in methanol.
3. Figure 3.3 Names of some C5 alcohols.
4. Figure 3.4 Some alcohols used as perfume ingredients.
5. Figure 3.5 Structures and alternative names for some phenols.
6. Figure 3.6 Some phenols present in essential oils.
7. Figure 3.7 Structures and alternative names of some ethers.
8. Figure 3.8 Some ethers of importance as perfume ingredients.
9. Figure 3.9 Structures and names of some simple aldehydes.
10. Figure 3.10 Some important perfumery aldehydes.
11. Figure 3.11 Naming of simple ketones.
12. Figure 3.12 Some ketones of importance in perfumery.
13. Figure 3.13 Some carboxylic acids.
14. Figure 3.14 Formation of ethyl acetate.
15. Figure 3.15 Some esters used in perfumery.
16. Figure 3.16 Acid anhydrides and chlorides .
17. Figure 3.17 Formation of acetals and ketals.
18. Figure 3.18 Some acetals and ketals of use in perfumery.
19. Figure 3.19 Peroxy functions of importance to perfumery.
20. Figure 3.20 Structures of amines and ammonium salts.
21. Figure 3.21 Inversion of amines.
22. Figure 3.22 Imines (Schiff's bases), enamines, and oximes.
23. Figure 3.23 Two Schiff's bases.
24. Figure 3.24 Formation and canonical forms of an amide.
25. Figure 3.25 Some perfumery nitriles.
26. Figure 3.26 Nitrobenzene and musk ketone.
27. Figure 3.27 Some classes of divalent sulfur compounds.
28. Figure 3.28 Dimethyl sulfoxide.
29. Figure 3.29 Classes of compounds with hexavalent sulfur .
30. Figure 3.30 Two sulfonic acids.
31. Figure 3.31 Some O‐ and S‐containing heterocyclic rings.
32. Figure 3.32 Some N‐containing heterocyclic rings.
33. Figure 3.33 Functional groups with carbon–oxygen single bonds.
34. Figure 3.34Figure 3.34 Functional groups with carbon–oxygen double bonds.
35. Figure 3.35Figure 3.35 Functional groups with oxygen–oxygen single bonds.
36. Figure 3.36Figure 3.36 Functional groups containing divalent sulfur.
37. Figure 3.37Figure 3.37 Functional groups containing tetravalent sulfur.
38. Figure 3.38Figure 3.38 Functional groups containing hexavalent sulfur.
39. Figure 3.39Figure 3.39 Functional groups with carbon–nitrogen single bonds.
40. Figure 3.40 Other nitrogen‐containing functional groups.
41. Figure 3.41 Selected fragrance ingredients.
Chapter 4
1. Figure 4.1 Crystal structure of sodium chloride .
2. Figure 4.2 Structure of Biradex N.
3. Figure 4.3 Actual shape of one molecule of Biradex N .
4. Figure 4.4 Crystal packing of Biradex N.
5. Figure 4.5 Unit cell of the diamond crystal structure.
6. Figure 4.6 Fragment of one sheet of graphite.
7. Figure 4.7 A simple phase diagram.
8. Figure 4.8 Surfactant molecules at an oil/water interface.
9. Figure 4.9 Anionic surfactants.
10. Figure 4.10 Neutral surfactants.
11. Figure 4.11 Cationic surfactants.
12. Figure 4.12 Zwitterionic surfactants.
13. Figure 4.13 Structure of emulsions.
14. Figure 4.14 Surfactants stabilising a droplet in a micelle.
15. Figure 4.15 Detergency in action.
16. Figure 4.16 A simple lipid bilayer.
17. Figure 4.17 Cross section of a mammalian cell wall.
18. Figure 4.18 Some components of the mammalian cell wall.
Chapter 5
1. Figure 5.1 A simple still.
2. Figure 5.2 Distillation under reduced pressure.
3. Figure 5.3 A fractionating still.
4. Figure 5.4 A Dean–Stark apparatus.
5. Figure 5.5 A steam still.
6. Figure 5.6 Natural extracts and isolates.
7. Figure 5.7 Basic principle of chromatography.
8. Figure 5.8 Thin layer chromatography.
9. Figure 5.9 A GC chromatogram of lavender oil.
10. Figure 5.10 GC chromatogram of lavender oil with enlarged vertical axis.
Chapter 6
1. Figure 6.1 A titration in progress.
2. Figure 6.2 The electromagnetic spectrum.
3. Figure 6.3 Spectroscopic techniques.
4. Figure 6.4 Splitting of white light into a spectrum.
5. Figure 6.5 Spectrum of a red dye.
6. Figure 6.6 Basic components of a spectrometer.
7. Figure 6.7 Spectrum of red dye of Figure 6.5 .
8. Figure 6.8 Some vibrations in water molecules.
9. Figure 6.9 Some characteristic infrared frequencies.
10. Figure 6.10 Alignment of magnetic nuclei in the presence of an external magneti...
11. Figure 6.11 Low‐resolution NMR spectrum of ethanol.
12. Figure 6.12 Proton NMR chemical shifts for some common functional groups.
13. Figure 6.13 Effect of neighbouring bonded atoms.
14. Figure 6.14 High‐resolution NMR spectrum of ethanol.
15. Figure 6.15 Chemical shifts in ¹³C NMR spectra.
16. Figure 6.16 Basic elements of a mass spectrometer.
17. Figure 6.17 Fragmentation of ethanol in the mass spectrometer.
18. Figure 6.18 Mass spectrum of ethanol.
19. Figure 6.19 Infrared spectrum of eugenol.
20. Figure 6.20 Ultraviolet spectrum of eugenol.
21. Figure 6.21 Proton NMR spectrum of eugenol.
22. Figure 6.22 13 Carbon DEPT spectrum of eugenol.
23. Figure 6.23 Mass spectrum of eugenol.
Chapter 7
1. Figure 7.1 An esterification/ester hydrolysis equilibrium.
2. Figure 7.2 A typical reaction profile.
3. Figure 7.3 (a) Exothermic and (b) endothermic reactions.
4. Figure 7.4 (a)‘Burning’ of TNT versus (b) burning of coal.
5. Figure 7.5 Formation of ions and radicals from methane.
6. Figure 7.6 Mechanistic illustration of formation of ions and radicals from meth...
7. Figure 7.7 Formation of an enolate anion.
8. Figure 7.8 Stabilisation of anions by hyperconjugation.
9. Figure 7.9 Stabilisation of a carbocation by conjugation.
10. Figure 7.10 Formation of carbocations.
11. Figure 7.11 The Diels–Alder reaction.
12. Figure 7.12 Some pericyclic reactions used to prepare fragrance ingredients.
Chapter 8
1. Figure 8.1 Brønsted acid/base neutralisation reaction.
2. Figure 8.2 Reactions of Lewis acids.
3. Figure 8.3 Franklin acids and bases.
4. Figure 8.4 Strong and weak acids and bases.
5. Figure 8.5 Acids and bases in water.
6. Figure 8.6 pH in consumer products.
7. Figure 8.7 Stability of perfume ingredients at various pH values.
8. Figure 8.8 Hydroxide as base or nucleophile.
9. Figure 8.9 Ester hydrolysis.
10. Figure 8.10 Acid‐catalysed esterification/ester hydrolysis.
11. Figure 8.11 Formation and loss of PTBCHA.
12. Figure 8.12 Tautomeric forms of an enolate anion.
13. Figure 8.13 The aldol reaction and aldol condensation .
14. Figure 8.14 The acid‐catalysed aldol reaction and aldol condensation.
15. Figure 8.15 Wanted and unwanted aldol condensations .
16. Figure 8.16 Formation of acetals.
17. Figure 8.17 (a) Wanted and (b) unwanted acetal formation .
18. Figure 8.18 Mechanism of formation of Schiff's bases and enamines.
19. Figure 8.19 Preparation of nitriles from aldehydes.
20. Figure 8.20 Dehydration of alcohols.
21. Figure 8.21 Acid‐catalysed addition to olefins.
22. Figure 8.22 Acid‐catalysed addition to cyclopropanes.
23. Figure 8.23 Nucleophilic addition to α,β‐unsaturated carbonyls.
24. Figure 8.24 Formation of a Grignard reagent.
25. Figure 8.25 Grignard reactions of carbonyl compounds.
26. Figure 8.26 Acetylide anion as a nucleophile.
27. Figure 8.27 The Friedel–Crafts alkylation reaction.
28. Figure 8.28 The Friedel–Crafts acylation reaction.
29. Figure 8.29 Directive effects of electron‐donating groups in aromatic rings.
30. Figure 8.30 Directive effects of electron‐withdrawing groups in aromatic rings.
31. Figure 8.31 Friedel–Crafts acetylation of anisole.
32. Figure 8.32 Fragrance ingredients for a laundry powder perfume.
33. Figure 8.33 Acid‐stable alcohols.
Chapter 9
1. Figure 9.1 Oxidation and reduction of iron.
2. Figure 9.2 A red‐ox cycle of chromium .
3. Figure 9.3 Oxidation levels of sulfur.
4. Figure 9.4 Oxidation of organosulfur compounds.
5. Figure 9.5 Oxidation levels of chlorine.
6. Figure 9.6 Formation of sodium hypochlorite.
7. Figure 9.7 Structures of sulfur and chlorine oxo‐acids _.
8. Figure 9.8 Peroxy species in organic chemistry.
9. Figure 9.9 Red‐ox states of hydrocarbons.
10. Figure 9.10 Oxidation levels of oxygenated organics.
11. Figure 9.11 The chloroform reaction.
12. Figure 9.12 Formation of peracetic acid from TAED/perborate.
13. Figure 9.13 Reaction of a peracid with an olefin.
14. Figure 9.14 Autoxidation of tetralin – initiation.
15. Figure 9.15 Autoxidation of tetralin – propagation.
16. Figure 9.16 Autoxidation of tetralin – termination.
17. Figure 9.17 Autoxidation in a perfume containing an aldehyde .
18. Figure 9.18 Oxidative decarbonylation of an aldehyde.
19. Figure 9.19 Autoxidation of fats.
20. Figure 9.20 Oxidative coupling of phenols.
21. Figure 9.21 Antioxidants.
Chapter 10
1. Figure 10.1 Perfume structure.
2. Figure 10.2 Odour intensity and concentration.
3. Figure 10.3 From bottle to nose.
Chapter 11
1. Figure 11.1 Acids used for prevention or removal of limescale.
2. Figure 11.2 Reaction of nucleophiles with perfume ingredients.
3. Figure 11.3 Alcohol stability to hypochlorite.
4. Figure 11.4 SNOBS/percarbonate bleach system.
5. Figure 11.5 Reaction of bisulfite with a carbonyl compound.
6. Figure 11.6 Reductants and antioxidants in consumer goods.
7. Figure 11.7 Making and breaking disulfide bridges using thioglycolic acid.
8. Figure 11.8 Chelating agents.
9. Figure 11.9 Photoactive ingredients in consumer goods.
10. Figure 11.10 Antibacterial agents.
11. Figure 11.11 Reactions of DHA with perfume ingredients .
12. Figure 11.12 Composition of fine fragrance.
13. Figure 11.13 Cosmetics and toiletries.
14. Figure 11.14 Personal wash.
15. Figure 11.15 Fabrics.
16. Figure 11.16 Household.
17. Figure 11.17 Stable in antiperspirants.
18. Figure 11.18 Stable in machine dishwashing powder.
Chapter 12
1. Figure 12.1 Polarisation of the O─H bond in methanol.
2. Figure 12.2 Hydrogen bonding in methanol.
3. Figure 12.3 Hydrogen bonding between methanol and benzene.
4. Figure 12.4 Hydrogen bonding in acetic acid.
5. Figure 12.5 Hydrophobic bonding .
6. Figure 12.6 Representations of glucose and fructose .
7. Figure 12.7 Formation of a glycoside.
8. Figure 12.8 Hydrolysis of amygdalin.
9. Figure 12.9 Formation of sucrose from glucose and fructose .
10. Figure 12.10 The four bases of nucleic acids.
11. Figure 12.11 Recognition between nucleotides.
12. Figure 12.12 Biosynthesis of fatty acids .
13. Figure 12.13 Some representative fatty acids.
14. Figure 12.14 Triglycerides .
15. Figure 12.15 Phospholipids and sphingolipids .
16. Figure 12.16 Some amino acids.
17. Figure 12.17 A cross section of a lipid bilayer and transmembrane protein.
18. Figure 12.18 Primary structure.
19. Figure 12.19 Secondary structure of proteins.
20. Figure 12.20 Tertiary structure of proteins.
21. Figure 12.21 Molecular organisation in an enzyme active site.
22. Figure 12.22 Selected LD₅₀ values.
23. Figure 12.23 Reaction of soft electrophiles with an amino function in a protein...
24. Figure 12.24 Bergaptene and allyl isothiocyanate.
25. Figure 12.25 ω‐Oxidation and β‐oxidation.
26. Figure 12.26 Oxidative degradation of benzene rings via epoxidation.
27. Figure 12.27 Degradation of aromatics by initial side chain oxidation.
28. Figure 12.28 Some natural substances.
29. Figure 12.29 Two cyclopentanone derivatives.
30. Figure 12.30 α‐Ionone and α‐damascone.
31. Figure 12.31 Selected alcohols.
Chapter 13
1. Figure 13.1 Key organs involved in human olfaction.
2. Figure 13.2 A seven‐transmembrane G‐protein‐coupled receptor.
3. Figure 13.3 View of an olfactory receptor protein from above the cell wall show...
4. Figure 13.4 The global toggle switch.
5. Figure 13.5 The sequence of events in converting a chemical signal (odorant) in...
6. Figure 13.6 A typical receptor odorant screening map.
7. Figure 13.7 Perception of one odorant.
8. Figure 13.8 Perception of a second odorant.
9. Figure 13.9 Perception of a mixture of two odorants.
10. Figure 13.10 Perception of a mixture of two odorants with interactions at recep...
11. Figure 13.11 Major neural pathways in olfactory perception.
Chapter 14
1. Figure 14.1 An antimicrobial sesquiterpenoid present in myrrh.
2. Figure 14.2 Adenosine triphosphate (ATP).
3. Figure 14.3 Nicotinamide adenine dinucleotide phosphate (NADP).
4. Figure 14.4 Coenzyme A.
5. Figure 14.5 General pattern of biosynthesis of secondary metabolites.
6. Figure 14.6 Polyketide biosynthesis.
7. Figure 14.7 Further steps in polyketide biosynthesis.
8. Figure 14.8 Reduction of a polyketide to form a fatty acid.
9. Figure 14.9 Arachidonic acid and the biosynthesis of jasmonic acid derivatives.
10. Figure 14.10 Key intermediates in the shikimic acid pathway.
11. Figure 14.11 Odorants from prephenic acid and phenylalanine.
12. Figure 14.12 Odorants from cinnamic acid.
13. Figure 14.13 Odorants from ferulic acid.
14. Figure 14.14 Isoprene and the head‐to‐tail linkage in terpenoids.
15. Figure 14.15 Three terpenoids and the isoprene units they contain.
16. Figure 14.16 Three key terpenoid building blocks and some hemiterpenoids.
17. Figure 14.17 The mechanism of coupling of isoprene units.
18. Figure 14.18 Formation of some typical monoterpenoids from geranyl pyrophosphat...
19. Figure 14.19 Some acyclic monoterpenoids.
20. Figure 14.20 Some cyclic monoterpenoids.
21. Figure 14.21 Formation of some typical sesquiterpenoids from farnesyl pyrophosp...
22. Figure 14.22 Tail‐to‐tail coupling and the biosynthesis of carotenoids.
23. Figure 14.23 Ionones and damascones.
24. Figure 14.24 Ambreine and some of its degradation products.
25. Figure 14.25 Formation of α‐irone.
26. Figure 14.26 Some common malodour components and their sources.
Chapter 15
1. Figure 15.1 Driving forces for the use of synthetic fragrance ingredients.
2. Figure 15.2 Hazard labels associated with citrus oils.
3. Figure 15.3 Typical ingredient life cycle.
4. Figure 15.4 Categories of fragrance ingredients.
5. Figure 15.5 Fragrance ingredients from castor oil.
6. Figure 15.6 Ethylene brassylate from rapeseed oil.
7. Figure 15.7 Some shikimate‐derived fragrance ingredients.
8. Figure 15.8 Key routes to citral and the rose alcohols.
9. Figure 15.9 The Barbier–Bouveault–Tiemann route to citral .
10. Figure 15.10 The Arens–van Dorp concept for synthesis of citral.
11. Figure 15.11 The Arens–van Dorp synthesis of citral .
12. Figure 15.12 The use of the Carroll reaction in the synthesis of citral .
13. Figure 15.13 The use of the Claisen rearrangement in the synthesis of citral.
14. Figure 15.14 Citral from isobutylene.
15. Figure 15.15 Fragrance ingredients from α‐pinene via pinane.
16. Figure 15.16 Some other products from α‐pinene.
17. Figure 15.17 Some fragrance ingredients from β‐pinene.
18. Figure 15.18 Fragrance ingredients from citrus oil components.
19. Figure 15.19 Fragrance ingredients from longifolene.
20. Figure 15.20 Fragrance ingredients from cedarwood oil.
21. Figure 15.21 Amber ingredients from clary sage.
22. Figure 15.22 Aliphatic fragrance ingredients from ethylene.
23. Figure 15.23 Butadiene as an intermediate.
24. Figure 15.24 Isobutylene as an intermediate.
25. Figure 15.25 Intermediates from acetone.
26. Figure 15.26 Benzene as feedstock.
27. Figure 15.27 Manufacture of the muguet aldehydes.
28. Figure 15.28 Benzylic oxidation of toluene.
29. Figure 15.29 Toluene as feedstock.
30. Figure 15.30 Naphthalene as feedstock.
31. Figure 15.31 Manufacture of phenol.
32. Figure 15.32 Phenol as feedstock.
33. Figure 15.33 Ingredients from phenol via guaiacol.
34. Figure 15.34 Adipic acid as feedstock.
35. Figure 15.35 Manufacture of methyl dihydrojasmonate.
36. Figure 15.36 Cyclopentadiene as feedstock.
37. Figure 15.37 Some nitro musks.
38. Figure 15.38 Some polycyclic musks.
39. Figure 15.39 Synthesis of Helvetolide.
40. Figure 15.40 Some macrocyclic musks.
41. Figure 15.41 Synthesis of macrocyclic musks by ring expansion.
42. Figure 15.42 Requirements of a fragrance ingredient.
43. Figure 15.43 From bottle to nose.
44. Figure 15.44 Successful fragrance ingredients designed using structure–odour re...
45. Figure 15.45 Büchi's synthesis of jasmone and methyl jasmonate.
Chapter 16
1. Figure 16.1 Specific and generalised structural formulae.
2. Figure 16.2 Chemical information process.
Chapter 17
1. Figure 17.1 Safety and natural chemicals.
2. Figure 17.2 Carene and cineole.
3. Figure 17.3 The β‐oxidation pathway.
4. Figure 17.4 Musk and sandalwood evolution.
5. Figure 17.5 Sclareol to Ambrofix.
6. Figure 17.6 The Symrise route to l‐menthol .
7. Figure 17.7 The Takasago route to l‐menthol .
8. Figure 17.8 The BASF route to l‐menthol .
9. Figure 17.9 Light‐induced release of odorants from a pro‐fragrance.
10. Figure 17.10 Metabolism of an odorant in the nose by known as CYP2A13.
11. Figure 17.11 Incensole acetate.

Introduction

To the layman, the world of perfumery conjures up images of glamour, dreams, romance, expensive oils extracted from exotic plants, and so on. The names that spring to mind are those of the great perfumers and fashion houses such as Jean Patou, Francois Coty, Chanel, Christian Dior, and so on. These names and images are part of our fascinating industry, but, in addition, behind all of this allure is a modern industry with a strong scientific basis, and the core science is chemistry. 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’. And his words are as true today as in 1921 when he created his famous masterpiece. Many Nobel Prize winners mentioned fragrance chemistry in their prizewinning lectures. It is also significant that the times of strongest growth of a fragrance company are associated, more often than not, with the presence of a first‐rate, practicing chemist in a senior position. Thus, to the names of the perfumers, we can add great chemists such as Yves‐Rene Naves (Givaudan), Ernst Theimer (IFF), Leopold Ruziča (Firmenich), Ernst Günther (Fritzsche, Dodge, and Olcott), Ernest Polak (Polak's Frutal Works), Paul José Teisseire (Roure Bertrand Dupont), Günther Ohloff (Firmenich), and George Fráter (Givaudan) as key figures in the history of perfumery. Not everyone needs to be a chemist of such a calibre as these, but for all of those individuals working in the fragrance business and in the consumer goods industries that it serves, knowledge of chemistry is invaluable in understanding how fragrance is produced, how it works, and the factors that control its performance in products.

Perfume molecules are compounds of carbon and hence come under the general heading of organic chemistry. Our bodies are also composed of organic chemicals and so are most of the components of consumer goods such as soaps and detergents. This book therefore concentrates on those aspects of organic chemistry, which are of particular importance to the fragrance industry. It is intended for those who have little or no previous training in chemistry and who would like to know enough in order to improve their understanding of perfume and its interactions with the wide variety of products in which it is used.

Chapter 1 covers the nature of matter, the building blocks from which it is made, and how these building blocks are held together.

Chapter 2 describes the basic concepts of how carbon atoms join together to form the backbones of organic chemicals. It also describes the various shorthand methods that chemists use to indicate the composition of materials and the structure of their molecules and so will enable participants to make sense of the ‘fried eggs and spiders’ that chemists draw. It also gives an insight into the language that chemists use and the names they give chemicals.

Chapter 3 introduces organic materials that contain oxygen, nitrogen, or sulfur as well as carbon and hydrogen. The vast majority of fragrance ingredients fall into this class.

Chapter 4 describes the three states of matter and how one may be converted into another. It also describes how surface‐active agents behave at interfaces between immiscible liquids and this behaviour leads on to cover the basis of detergency and the structure of mammalian cell walls.

In order to analyse and manipulate materials, it is important to be able to isolate them from mixtures and obtain them in pure form. The various methods by which purification can be achieved both for analytical and manufacturing purposes are described in Chapter 5.

Chapter 6 concerns the methods used to identify and characterise perfume molecules, an activity of vital importance for everything from purchasing of raw materials to studying the fate of fragrance materials after use.

Chapter 7 outlines the factors controlling chemical reactivity and provides a basis for understanding of the chemistry to be described in the subsequent chapters. The chemistry of acids and bases and the relevance of this chemistry to perfume chemistry is the subject of Chapter 8, while Chapter 9 covers oxidation and reduction reactions.

Chapter 10 describes the structure of a fragrance and the effects of this on performance in consumer goods. Chapter 11 discusses the chemical interactions that occur between perfume ingredients and the other materials present in consumer goods.

Chapter 12 gives a very basic introduction to the chemistry of living organisms, and this paves the way for a discussion of the mechanism of olfaction in Chapter 13. Chapter 14 moves on to describe the variety of chemicals made by plants and animals and, in particular, those that constitute the essential oils and other fragrant extracts.

Chapter 15 follows on by describing how we copy and improve upon the perfume ingredients of nature in order to provide the perfumers with the palette available to them today.

Chapter 16 provides a brief introduction to chemical literature, and it also contains a list of recommended reading. Thus, it serves as a guide for the reader who wishes to pursue the subject in more detail.

The last chapter, Chapter 17, surveys the trends that are likely to affect the industry in the future and how we can respond to these to make the industry as sustainable as possible.

Fundamentals of Fragrance Chemistry

Copyright

Preface

Introduction