Stereochemistry of Organic Compounds

Contents
About the Author
Part I Introduction
1 Introduction
	1.1 Introduction
Part II Stereochemistry of Organic Compounds
2 Stereochemistry of Organic Compounds Containing Carbon–Carbon Single Bonds (Hydrocarbons)
	2.1 Introduction
	2.2 Projection Formula of Conformers
	2.3 Conformations of Ethane
	2.4 Conformations of Butane
	2.5 Conformations of Cycloalkanes
		2.5.1 Stability of Cycloalkanes
		2.5.2 Conformations of Cyclopropane
		2.5.3 Conformations of Cyclobutane
		2.5.4 Conformations of Cyclopentane
		2.5.5 Conformations of Cyclohexane
		2.5.6 Conformations of Fused Six-Membered Rings
3 Stereochemistry of Organic Alicyclic Compounds Containing Carbon–Carbon Double Bonds (Alkenes and Cycloalkenes)
	3.1 Introduction
	3.2 Restricted Rotation Around a Carbon–Carbon Double Bond
	3.3 Cis–Trans Isomerism
	3.4 E and Z System of Nomenclature
	3.5 Relative Stabilities of Cis and Trans Alkenes
		3.5.1 From Heat of Hydrogenation
		3.5.2 Heat of Combustion
	3.6 Synthesis of Cis and Trans Alkenes
		3.6.1 Synthesis of Cis Alkenes (Catalytic Reduction)
		3.6.2 Synthesis of Trans Alkenes (Chemical Reduction)
	3.7 Characterisation of Cis and Trans Isomers
		3.7.1 Physical Properties
		3.7.2 Chemical Reactions
	3.8 Interconversion of Cis–Trans Isomers
		3.8.1 Photoisomerisation of Cis and Trans Isomers
		3.8.2 Conversion of One Isomer (Cis or Trans) into Another Isomer (Trans or Cis)
	3.9 Cis–Trans Isomerism in Conjugated Dienes
	3.10 Cis–Trans Isomerism in Cumulenes
	3.11 Cis–Trans Isomerism Due to Restricted Rotation About C–N Bonds
	3.12 Cis–Trans Isomerism in Terphenyl Compounds
	3.13 Stereochemistry of Cycloalkenes
4 Stereochemistry of Organic Compounds Containing Asymmetric Carbon
	4.1 Introduction
	4.2 Origin of Optical Activity
	4.3 Measurement of Optical Activity
	4.4 Optical Isomerism
		4.4.1 Chirality
		4.4.2 Optical Isomerism in Compounds Having One Stereogenic Centre
		4.4.3 Optical Isomerism in Compounds Having Two Asymmetric Centres (Stereogenic Centres)
		4.4.4 Relative Configuration of Stereoisomers (D and L System of Nomenclature)
		4.4.5 Absolute Configuration of Stereoisomers (R and S-system of Nomenclature)
		4.4.6 Optical Isomerism in Compounds Having More Than Two Stereogenic Centres
	4.5 Racemic Mixture
		4.5.1 Formation of Racemic Mixtures
		4.5.2 Resolution of Racemic Mixture
	4.6 Optical Purity of Enantiomers
5 Symmetry Elements
	5.1 Introduction
	5.2 Elements of Symmetry
		5.2.1 Plane of Symmetry
		5.2.2 Centre of Symmetry
		5.2.3 Alternating Axis of Symmetry
6 Stereochemistry of Optically Active Compounds Having no Asymmetric Carbon Atoms
	6.1 Stereochemistry of Biphenyls
		6.1.1 Absolute Configuration of Biphenyls
		6.1.2 Atropisomerism
		6.1.3 Racemisation of Biphenyls
	6.2 Stereochemistry of Optically Active Compounds Due to Intramolecular Crowding
	6.3 Stereochemistry of Allenes
	6.4 Stereochemistry of spirans
	6.5 Ansa Compounds
	6.6 Cyclophanes
	6.7 Benzocycloalkanes
	6.8 Helicenes
	6.9 Annulenes
7 Stereochemistry of Trivalent Carbon
	7.1 Introduction
	7.2 Carbocations
		7.2.1 Structure and Stability of Carbocations
		7.2.2 Generation of Carbocations
		7.2.3 Reactions of Carbocations
		7.2.4 Stereochemistry of Rearrangements Involving Carbocations
	7.3 Carbanions
		7.3.1 Stability of Carbonians
		7.3.2 Structure of Carbanions
		7.3.3 Generation of Carbanions
		7.3.4 Reactions of Carbanions
		7.3.5 Reactions Involving Carbanions
	7.4 Free Radicals
		7.4.1 Structure and Stability of Free Radicals
		7.4.2 Heteroradicals
		7.4.3 Generation of Free Radicals
		7.4.4 Reaction of Free Radicals
		7.4.5 Reactions Involving Free Radicals
8 Stereochemistry of Fused, Bridged and Caged Rings and Related Compounds
	8.1 Introduction
	8.2 Fused Rings
		8.2.1 Fused Ring Compounds Containing Two Rings (Bicyclic Compounds)
		8.2.2 Fused Polycyclic Compounds
	8.3 Bridged Compounds
		8.3.1 Stereochemical Implications of Bridged Compounds
	8.4 Catenanes, Rotaxanes and Knots
		8.4.1 Catenanes
		8.4.2 Rotaxanes
	8.5 Cubane, Prismane, Adamantane, Twistane, Buckminsterfullerene and Tetra-Tert-Butyl Tetrahedrane
		8.5.1 Cubane
		8.5.2 Prismane
		8.5.3 Adamantane
	8.6 Proposed Mechanism
		8.6.1 Twistane
		8.6.2 Buckminsterfullerene
		8.6.3 Tetra-Tert-Butyltetrahedrane
9 Optical Rotatory Dispersion and Circular Dichroism
	9.1 Introduction
	9.2 Circular Birefringence
	9.3 Circular Dichroism
	9.4 Cotton Effect
	9.5 Optical Rotatory Dispersion (ORD)
		9.5.1 Types of Optical Rotatory Dispersion Curves
	9.6 Comparison of ORD and CD Curves
	9.7 Axial Haloketone Rule
	9.8 The Octant Rule
	9.9 Instrumentation for ORD and CD Measurements
		9.9.1 Instruments for ORD Measurements
		9.9.2 Instrumentation for CD Measurements
	9.10 Applications of Optical Rotatory Dispersion and Circular Dichroism
Part III Stereochemistry of Reactions
10 Stereochemistry of Addition Reactions
	10.1 Introduction
	10.2 Electrophilic Addition Reactions
		10.2.1 Electrophilic Addition Reactions of Alkenes
		10.2.2 Electrophilic Addition Reactions of Alkynes
	10.3 Nucleophilic Addition Reactions
		10.3.1 Nucleophilic Addition of –CN
		10.3.2 Nucleophilic Addition of Water
		10.3.3 Nucleophilic Addition of Hydrogen Halides
		10.3.4 Addition of Wittig Reagent
	10.4 Addition Reactions of Conjugated Dienes
		10.4.1 Addition of HBr
		10.4.2 Cycloaddition Reactions
		10.4.3 Addition of Halogens
	10.5 Free Radical Addition Reactions
		10.5.1 Introduction
		10.5.2 Electrophilic Addition of HBr to Unsymmetrical Alkenes
	10.6 Free Radical Polymerisation
11 Stereochemistry of Elimination Reactions
	11.1 Introduction
	11.2 Bimolecular Elimination Reactions (E2)
		11.2.1 Stereochemistry of E2 Reaction
	11.3 Unimolecular Elimination Reaction (E1)
	11.4 Elimination Reactions in Alcohols
	11.5 Elimination of HBr from Bromobenzene (Formation of Benzyne as an Intermediate)
	11.6 Eliminations Involving Ammonium Compounds
		11.6.1 Hofmann Elimination
		11.6.2 Cope Elimination
	11.7 Elimination Reaction of -Hydroxycarbonyl Compounds
	11.8 Comparison of E1 and E2 Mechanisms
	11.9 Synthesis of Alkynes
12 Stereochemistry of Substitution Reactions
	12.1 Introduction
	12.2 Free Radical Substitution Reactions
		12.2.1 Conversion of Methane into Carbon Tetrachloride
		12.2.2 Conversion of Benzene into Benzene Hexachloride
		12.2.3 Conversion of Toluene into Benzyl Chloride
		12.2.4 Conversion of Propene into n-Propyl Bromide
		12.2.5 Allylic Substitution
		12.2.6 Vinylic Substitution
		12.2.7 Benzylic Bromination
	12.3 Electrophilic Substitution Reaction of Monosubstituted Benzenes
		12.3.1 Nitration
		12.3.2 Halogenation
		12.3.3 Sulfonation
		12.3.4 Alkylation
		12.3.5 Acylation
		12.3.6 Effect of Substitutions in the Electrophilic Substitutions in Monosubstituted Benzenes
	12.4 Electrophilic Substitutions in Disubstituted Benzenes
	12.5 Nucleophilic Substitution Reactions
		12.5.1 Bimolecular Nucleophilic Substitution (SN2)
		12.5.2 Unimolecular Nucleophilic Substitution (SN1)
		12.5.3 Nucleophilic Substitutions in Allylic and Benzylic Halides
	12.6 Substitution Reaction of Alcohols
		12.6.1 Conversion of OH of Alcohols into +OH2
		12.6.2 Conversion of Alcohols into Tosylates or Mesylates
		12.6.3 Mitsunobu Reaction
	12.7 Substitution Reactions of Ethers
	12.8 Substitution Reactions of Epoxides
	12.9 Substitution Reaction of Thiols
	12.10 Substitution Reactions of Thioethers
	12.11 Aromatic Substitution
		12.11.1 Nucleophilic Aromatic Substitution
		12.11.2 Electrophilic Aromatic Substitution
	12.12 Substitution Reactions of Aryl Diazonium Salts
		12.12.1 Substitution by OH
		12.12.2 Substitution by Cl, Br and CN
		12.12.3 Substitution by I
		12.12.4 Substitution by H
		12.12.5 Substitution by F
	12.13 Substitution of Sulphonic Acid Group in Benzene Sulphonic Acid
		12.13.1 Substitution by OH
		12.13.2 Substitution by NH2
		12.13.3 Substitution of CN
		12.13.4 Substitution by SH
		12.13.5 Substitution by NO2 Group
		12.13.6 Substitution by Br
	12.14 Substitution of Active Hydrogen by Alkyl and Acyl Groups
	12.15 Substitution of Hydroxyl Group of Alcohols by Cl or Br
		12.15.1 Reaction with HX
		12.15.2 Reaction with Thionyl Chloride
		12.15.3 Reaction with Phosphorus Halide
	12.16 Substitutions in Carboxylic Acids
		12.16.1 Substitution of OH of Carboxyl Group by Cl, OR or NH2
		12.16.2 Substitution of COOH Group by Bromine
		12.16.3 Substitution of α-hydrogen in Carboxylic Acids by Br
13 Stereochemistry of Rearrangement Reactions
	13.1 Introduction
	13.2 Classification of Rearrangement Reactions
		13.2.1 Classification as Intramolecular or Intermolecular Rearrangements
		13.2.2 Rearrangements Reactions Involving Carbon–Carbon Rearrangements
		13.2.3 Rearrangement Reactions Involving Carbon–Nitrogen Rearrangements
		13.2.4 Rearrangement Reactions Involving Carbon–Oxygen Rearrangements
		13.2.5 Rearrangement Reactions
14 Stereochemistry of Pericyclic Reaction
	14.1 Introduction
	14.2 Types of Pericyclic Reactions
	14.3 Stereochemistry of Pericyclic Reactions
	14.4 Some Useful Concepts that Come from Quantum Mechanics
	14.5 Molecular Orbital Theory
		14.5.1 Molecular Orbitals of Ethene
		14.5.2 Molecular Orbitals of Butadiene
		14.5.3 Molecular Orbitals of 1, 3, 5-Hexatriene
		14.5.4 Symmetry Properties of Orbitals
	14.6 Electrocyclic Reactions
		14.6.1 Frontial Molecular Orbital (FMO) Method
	14.7 Cycloaddition Reactions
		14.7.1 [2 + 2] Cycloadditions
		14.7.2 [4 + 2] Cycloadditions
		14.7.3 1,3-Dipolar Cycloadditions
	14.8 Sigmatropic Rearrangements
		14.8.1 Hydrogen Shifts
		14.8.2 Analysis of Sigmatropic Rearrangements
		14.8.3 Carbon Shifts
Part IV Stereochemistry of Heterocyclic Compounds
15 Stereochemistry of Some Compounds Containing Heteroatoms
	15.1 Stereochemistry of Nitrogen Compounds
		15.1.1 Stereochemistry of Amines
		15.1.2 Stereochemistry of Quaternary Ammonium Salts
		15.1.3 Stereochemistry of Tertiary Amine Oxides
		15.1.4 Stereochemistry of Oximes
		15.1.5 Stereochemistry of Some Tetravalent Nitrogen Compounds Containing a Double Bond
		15.1.6 Stereochemistry of Some Heterocyclic Compounds Containing Nitrogen
	15.2 Stereochemistry of Organophosphorus Compounds
		15.2.1 Stereochemistry of Tertiary Phosphines
		15.2.2 Stereochemistry of Quaternary Phosphonium Salts
		15.2.3 Stereochemistry of Tertiary Phosphine Oxides
	15.3 Stereochemistry of Cyclic Phosphorus Compounds
	15.4 Stereochemistry of Sulphur Compounds
		15.4.1 Stereochemistry of Sulphonium Salts
		15.4.2 Stereochemistry of Sulphinic Esters
		15.4.3 Stereochemistry of Sulphoxides
	15.5 Stereochemistry of Sulphilimines
		15.5.1 Stereochemistry of Sulphines
16 Stereochemistry of Some Heterocyclic Compounds
	16.1 Three-Membered Heterocyclic Compounds
		16.1.1 Three-Membered Saturated Heterocyclic Compounds
		16.1.2 Three-Membered Unsaturated Heterocyclic Compounds
		16.1.3 Three-Membered Heterocyclic Compounds with Two Heteroatoms
	16.2 Four-Membered Heterocyclic Compounds
		16.2.1 Oxetanes
		16.2.2 Azetidines
		16.2.3 Thietanes
	16.3 Five-Membered Heterocyclic Compounds with One Heteroatom
		16.3.1 Benzo-Fused Five-Membered Heterocyclic Compounds with One Heteroatom
		16.3.2 Dibenzoheterocyclic Compounds with One Heteroatom
		16.3.3 Five-Membered Heterocyclic Compounds with Two Heteroatoms
	16.4 Six-Membered Heterocyclic Compounds
		16.4.1 Pyridine
		16.4.2 Piperidine
		16.4.3 Decahydroquinolines
		16.4.4 1,3-Dioxans
		16.4.5 1,4-Dioxans
17 Stereochemistry of Biomolecules
	17.1 Carbohydrates
		17.1.1 Glucose
		17.1.2 Fructose
		17.1.3 Sucrose
		17.1.4 Lactose
		17.1.5 Maltose
		17.1.6 Trehalose
		17.1.7 Raffinose
		17.1.8 Gentibiose
		17.1.9 Cellulose
		17.1.10 Starch
	17.2 Proteins
		17.2.1 Biologically Important Peptides
		17.2.2 Stereochemistry of Proteins
	17.3 Nucleic Acids
		17.3.1 Nucleotides
	17.4 Nucleic Acids
		17.4.1 Primary Structure
		17.4.2 Secondary Structure of Nucleic Acids (DNA)
		17.4.3 Tertiary Structure of DNA
Part V Stereoselective Synthesis and Organic Reactions
18 Stereoselective Synthesis
	18.1 Introduction
	18.2 Importance of Stereoselective Synthesis
	18.3 Enantioselective Synthesis
		18.3.1 Using a Chiral Starting Synthon
		18.3.2 Enantioselectie Epioxidations
		18.3.3 Epoxides as Synthons for Stereoselective Sysnthesis
		18.3.4 Dihydroxylation of Alkenes
		18.3.5 Stereoselective Reduction of Alkynes
		18.3.6 Enantioselective Hydrogenations of Alkenes
		18.3.7 Enantioselective Hydroboration
		18.3.8 Enantioselectivity Using Organometallic Reagents
		18.3.9 Enantioselective Reduction of Carbonyl Groups
19 Enantioselective-Stereoselective Organic Reactions
	19.1 Aldol Reaction
		19.1.1 Directed Aldol Reaction
		19.1.2 Stereoselective Aldol Reaction
		19.1.3 Enantioselective Aldol Reaction
	19.2 Baeyer–Villiger Reaction
		19.2.1 Enzymatic Baeyer–Villiger Reaction
	19.3 Diels Alder Reaction
		19.3.1 Regio Selectivity in Diels Alder Reaction
		19.3.2 Stereoselectivity in Diels–Alder Reaction
		19.3.3 Catalystic Diels–Alder Reaction
		19.3.4 Asymmetric Diels–Alder Reaction
	19.4 Ene Reaction
		19.4.1 Catalytic Ene Reaction
		19.4.2 Stereoselectivity in Ene Reaction
		19.4.3 Intramolecular Ene Reaction
		19.4.4 Chiral Ene Reaction
	19.5 Enamine Reaction
		19.5.1 Asymmetric Enamine Synthesis
	19.6 Friedel Crafts Reaction
		19.6.1 Asymmetric Induction in Friedel Crafts Reaction
		19.6.2 Regioselectivity in Friedel Crafts Synthesis
	19.7 Grignard Reaction
		19.7.1 Asymmetric Induction in Grignard Reaction
		19.7.2 Stereoselectivity in the Formation of Vinyl Magnesium Halides from Appropriate Alkenes
	19.8 Corey-Posner, Whites-House Synthesis
	19.9 Sharpless Epoxidation Reaction
	19.10 Wittig Reaction
	References
Index