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