Contents Contents

1. Introduction 1

1.1. TheFieldofOrganic Chemistry 1 1.2. Origin of Natural Compounds 2 1.3. Classes of Natural Compounds 7 1.4. TheCovalent Bond 8 1.5. BondDissociation Energy 9 1.6. BondPolarization andElectronegativity 12 1.7. Dipole Moment 15 1.8. IntermolecularInteractions 17 1.9. Vander Waals Forces 17 1.10. Mechanisms of ChemicalReactions 19 1.11. Kinetics of ChemicalReactions 21 1.12. Stable and Reactive Molecules 31 1.13. Molecular Shape 34 1.14. Isomerism 38 1.15. Functional Groups 39 1.16. Nomenclature of Organic Compounds 40

2. Alkanes 43

2.1. Hydrocarbons 43 2.2. Origin of Petroleum 44 2.3. Isomerism of Alkanes 46 2.4. Nomenclature of Hydrocarbons 46 2.5. Methane 48 2.6. Structure of the MethaneMolecule 49 2.7. Chirality 50 2.8. Chirality and Symmetry 51 2.9. Optical Activity 56 2.10. Specification of MolecularChirality 61 2.11. Diastereoisomers 64 2.12. Experimental Determination of BondEnergies 69 2.13. Determination of the MolecularFormulasofOrganic Compounds 73 2.14. Mechanism of Combustion: Radical Substitution 74

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2.15. Transition States in Chemical Reactions 77 2.16. Respiration 79 2.17. Enzymatic Oxidation of Alkanes 83 2.18. Ethane 87 2.19. ConformationalIsomers 88 2.20. Butane 90 2.21. Cycloalkanes 91 2.22. Cyclohexane 94 2.23. Alkylcyclohexanes 96 2.24. Polycyclic Alkanes 99 2.25. Nomenclature of Polycycloalkanes 100

3. Unsaturated Hydrocarbons 103

3.1. Alkenes 103 3.2. Ethylene 104 3.3. p-Conformers: (Z/E)-Isomerism 106 3.4. Reactivity of Alkenes 107 3.5. Catalytic Hydrogenation 107 3.6. Stereoselectivity of Catalytic Hydrogenation 109 3.7. Stereospecificity 110 3.8. Electrophilic Addition 112 3.9. Regioselectivity of Electrophilic Addition: MarkovnikovsRule 114 3.10. Prochirality 115 3.11. Polymerization 117 3.12. Conjugated Alkenes 121 3.13. Theory of 121 3.14. Resonance Energy 123 3.15. 1,4-Addition 124 3.16. The DielsÀAlder Reaction 125 3.17. TheAllylic Bond 126 3.18. Sigmatropic Rearrangements 126 3.19. Terpenes 129 3.20. Semiochemicals 140 3.21. Pigments 142 3.22. Carotenoids 145 3.23. Reactivity of Photoexcited Molecules 149 3.24. Electrocyclic Reactions 151 3.25. Autoxidation 151 3.26. Cycloalkenes 156 3.27. Allenes andAlkynes 160

4. Aromatic Hydrocarbons 165

4.1. Aromaticity 165

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4.2. Polycyclic Aromatic Hydrocarbons 170 4.3. Valence Isomers 174 4.4. Electrophilic Aromatic Substitution 175 4.5. TheInductive Effect 177 4.6. PericyclicReactions 179 4.7. Biogenesis of Benzene Derivatives 180

5. ,Phenols,and Their Derivatives 183

5.1. Nomenclature of Alcohols 183 5.2. Biosynthesis of Alcohols 184 5.3. Polyalcohols 186 5.4. Reactivity of Alcohols 188 5.5. Hydrogen Bonding 188 5.6. Acidity of Alcohols 189 5.7. Polar and NonpolarSolvents 191 5.8. Phenols 191 5.9. Reactivity of Phenols: the Mesomeric Effect 193 5.10. Oxidation NumbersofCarbon Atoms 198 5.11. Oxidation of Alcohols 199 5.12. Oxidation of Phenols 199

5.13. The SN2Reaction 202 5.14. IntermolecularDehydration of Alcohols: Ether Formation 205 5.15. Unimolecular Nucleophilic Substitution

(SN1Reaction) 206 5.16. The Walden Inversion 209

5.17. The SN1’ Reaction 210 5.18. Reactivity of Carbenium Ions 211 5.19. Dehydration of Alcohols 212 5.20. Regioselectivity of the E1Reaction 213 5.21. Wagner –Meerwein Rearrangement 214 5.22. Pinacol Rearrangement 217 5.23. Ethers 218 5.24. Reactivity of Ethers 220 5.25. AirOxidation of Ethers 221 5.26. Oxonium Salts 222 5.27. Epoxides 223 5.28. Steroids 229

6. Thiols and Their Derivatives 233

6.1. Thiols and Thioethers 233 6.2. Disulfides 235 6.3. Redox Reactions 236

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6.4. Sulfoxides andSulfones 242 6.5. OrganicSulfurAcids 243

7. Amines 245

7.1. Nomenclature of Amines 245 7.2. Structures of Amines 246 7.3. Biogenic Amines 247 7.4. Hormones 251 7.5. Alkaloids 254 7.6. Reactivity of Amines 256 7.7. Basicity of Amines 256 7.8. Nucleophilicity of Amines 258 7.9. The Hofmann Elimination 260 7.10. Aromatic Amines 261 7.11. Formation of DiazoniumIons 263 7.12. Dyes 264 7.13. Chemotherapy 266

8. Carbonyl Compounds 271

8.1. TheCarbonyl Group 271 8.2. Steroid Hormones 272 8.3. Quinones 276 8.4. Quinones in Cell Metabolism 277 8.5. Natural Pigments 279 8.6. Reactivity of the 282 8.7. The 285 8.8. Polymerization of Aldehydes 286 8.9. The a-Ketol Rearrangement 287 8.10. Reactivity of Aldehydes and Ketones 288 8.11. Reduction of the Carbonyl Group 288 8.12. Oxidation of the Carbonyl Group 290 8.13. Nucleophilic Addition of Alcohols: Formation of Acetals 294 8.14. Nucleophilic Addition of Amines: Imine Formation 296 8.15. Reduction of Imines 301 8.16. CÀH-Acidic Compounds: Enolates 302 8.17. Oxidation of Enolates 307 8.18. EnolEthers: Claisen Rearrangement 309 8.19. Imine –Enamine Tautomerism 310 8.20. Aldol Addition 311 8.21. ThePrinciple of Vinylogy: Michael Addition 315 8.22. Cyanohydrins: the Benzoin Condensation 316 8.23. Carbohydrates 318 8.24. FischersSpecification of Chirality 319

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8.25. Structures of Monosaccharides 323 8.26. Conformations of Sugar Molecules 327 8.27. Analytical Tests for Saccharides 328 8.28. Prebiotic Synthesis of Monosaccharides 330 8.29. Metabolism of Monosaccharides 333 8.30. SugarAcids 335 8.31. Disaccharides 338 8.32. Glycosides 341 8.33. Polysaccharides 342

9. Carboxylic and Their Derivatives 351

9.1. Nomenclature of Carboxylic Acids 351 9.2. Acidity of Carboxylic Acids 352 9.3. Saturated Carboxylic Acids 357 9.4. Unsaturated Carboxylic Acids 358 9.5. Hydroxy and Oxo Carboxylic Acids 361 9.6. Amino Acids 370 9.7. Nonproteinogenic Amino Acids 373 9.8. Biosynthesis of Amino Acids 373 9.9. Metabolism of Amino Acids 378 9.10. Aromatic Carboxylic Acids 382 9.11. Reactivity of Carboxylic Acids 385 9.12. Carboxylic Anhydrides 385 9.13. Decarboxylation 386 9.14. Exchange of O-Atoms 393 9.15. Esterification 394 9.16. Lipids 398 9.17. Reactivity of Esters 405 9.18. Hydrolysis of Esters 406 9.19. Transesterification 407 9.20. Ammonolysis of Esters 408 9.21. Ester Enolates: Claisen Condensation 409 9.22. Thiocarboxylic Acids 413 9.23. Metabolism of Fatty Acids 414 9.24. Acetogenins 418 9.25. Amides 423 9.26. Amide-Like Functional Groups 425 9.27. Reactivity of Amides 429 9.28. Peptides 431 9.29. Structures of Peptides 433 9.30. Oligopeptides 437 9.31. Proteins 442 9.32. Enzymes 451 9.33. Metabolism of Proteins 458

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9.34. Nitriles 461 9.35. Prebiotic Synthesis of Amino Acids 463

10. Heterocyclic Compounds 465

10.1.Nomenclature of Heterocycles 465 10.2.Heteroaromatic Compounds 467 10.3.Azoles 468 10.4.Pyrrole Pigments 472 10.5.1H-Indole 476 10.6.Indole Alkaloids 481 10.7.Oxazoles 484 10.8.Imidazoles 484 10.9.Thiazoles 486 10.10. Azines 488 10.11. Benzopyridines 495 10.12. Tautomerism of Heteroaromatic Compounds 502 10.13. Diazines 504 10.14. Pteridines 506 10.15. Purines 513 10.16. Nucleosides and Nucleotides 517 10.17. Nucleic Acids 524 10.18. TheRole of Nucleic Acids 529 10.19. Biosynthesis of Nucleic Acids 541 10.20. Prebiotic Synthesis of Nucleotides 544 10.21. Catabolism of Nucleotides 547

Exercises 555

Chapter 1 555 Chapter 2 556 Chapter 3 557 Chapter 4 560 Chapter 5 561 Chapter 6 565 Chapter 7 566 Chapter 8 568 Chapter 9 574 Chapter 10 582

Answers 585

Chapter 1 585 Chapter 2 586 Chapter 3 588

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Chapter 4 590 Chapter 5 592 Chapter 6 596 Chapter 7 597 Chapter 8 601 Chapter 9 606 Chapter 10 614

Glossary 617

Index 629

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