Buch, Englisch, 1382 Seiten, Format (B × H): 225 mm x 284 mm, Gewicht: 3602 g
Theory, Reactivity and Mechanisms in Modern Synthesis
Buch, Englisch, 1382 Seiten, Format (B × H): 225 mm x 284 mm, Gewicht: 3602 g
ISBN: 978-3-527-34532-8
Verlag: Wiley-VCH GmbH
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Weitere Infos & Material
Preface xv
Foreword xxix
1 Equilibria and thermochemistry 1
1.1 Introduction 1
1.2 Equilibrium-free enthalpy: reaction-free energy or Gibbs energy 1
1.3 Heat of reaction and variation of the entropy of reaction (reaction entropy) 2
1.4 Statistical thermodynamics 4
1.4.1 Contributions from translation energy levels 5
1.4.2 Contributions from rotational energy levels 5
1.4.3 Contributions from vibrational energy levels 6
1.4.4 Entropy of reaction depends above all on the change of the number of molecules between products and reactants 7
1.4.5 Additions are favored thermodynamically on cooling, fragmentations on heating 7
1.5 Standard heats of formation 8
1.6 What do standard heats of formation tell us about chemical bonding and ground-state properties of organic compounds? 9
1.6.1 Effect of electronegativity on bond strength 10
1.6.2 Effects of electronegativity and of hyperconjugation 11
1.6.3 p-Conjugation and hyperconjugation in carboxylic functions 12
1.6.4 Degree of chain branching and Markovnikov’s rule 13
1.7 Standard heats of typical organic reactions 14
1.7.1 Standard heats of hydrogenation and hydrocarbation 14
1.7.2 Standard heats of C–H oxidations 15
1.7.3 Relative stabilities of alkyl-substituted ethylenes 17
1.7.4 Effect of fluoro substituents on hydrocarbon stabilities 17
1.7.5 Storage of hydrogen in the form of formic acid 18
1.8 Ionization energies and electron affinities 20
1.9 Homolytic bond dissociations; heats of formation of radicals 22
1.9.1 Measurement of bond dissociation energies 22
1.9.2 Substituent effects on the relative stabilities of radicals 25
1.9.3 p-Conjugation in benzyl, allyl, and propargyl radicals 25
1.10 Heterolytic bond dissociation enthalpies 28
1.10.1 Measurement of gas-phase heterolytic bond dissociation enthalpies 28
1.10.2 Thermochemistry of ions in the gas phase 29
1.10.3 Gas-phase acidities 30
1.11 Electron transfer equilibria 32
1.12 Heats of formation of neutral, transient compounds 32
1.12.1 Measurements of the heats of formation of carbenes 32
1.12.2 Measurements of the heats of formation of diradicals 33
1.12.3 Keto/enol tautomerism 33
1.12.4 Heat of formation of highly reactive cyclobutadiene 36
1.12.5 Estimate of heats of formation of diradicals 36
1.13 Electronegativity and absolute hardness 37
1.14 Chemical conversion and selectivity controlled by thermodynamics 40
1.14.1 Equilibrium shifts (Le Chatelier’s principle in action) 40
1.14.2 Importance of chirality in biology and medicine 41
1.14.3 Resolution of racemates into enantiomers 43
1.14.4 Thermodynamically controlled deracemization 46
1.14.5 Self-disproportionation of enantiomers 48
1.15 Thermodynamic (equilibrium) isotopic effects 49
1.A Appendix, Table 1.A.1 to Table 1.A.24 53
References 92
2 Additivity rules for thermodynamic parameters and deviations 109
2.1 Introduction 109
2.2 Molecular groups 110
2.3 Determination of the standard group equivalents (group equivalents) 111
2.4 Determination of standard entropy increments 113
2.5 Steric effects 114
2.5.1 Gauche interactions: the preferred conformations of alkyl chains 114
2.5.2 (E)- vs. (Z)-alkenes and ortho-substitution in benzene derivatives 117
2.6 Ring strain and conformational flexibility of cyclic compounds 117
2.6.1 Cyclopropane and cyclobutane have nearly the same strain energy 118
2.6.2 Cyclopentane is a flexible cycloalkane 119
2.6.3 Conformational analysis of cyclohexane 119
2.6.4 Conformational analysis of cyclohexanones 121
2.6.5 Conformational analysis of cyclohexene 122
2.6.6 Medium-sized cycloalkanes 122
2.6.7 Conformations and ring strain in p