The synthetic chemist thrives on the ability to take a seemingly simple molecule and create something more complex and more valuable. In general, substances which are readily available and highly abundant serve as the starting materials while the identity of the product is left to the imagination of the chemist (or market demands). Hydrocarbon feedstocks such as petroleum and natural gas have dominated the chemical industry for the last 50 years; not only because they have dramatic implications for the energy sector, but also because they represent plentiful precursors which the synthetic chemist can transform into value-added products.
Mechanistic aspects of organometallic transformations such as polymerization, C-H activation, and protonolysis have been examined. Relationships between catalyst geometry and polymer microstructure were defined. The mechanism of an intramolecular C-H activation process was found to involve two competing pathways.
The protonolysis of platinum methyl complexes was investigated for kinetic isotope effects and observation of intermediates. Bisphenolate ligands with pyridine- and benzene-diyl linkers were synthesized and metalated with group 4 and 5 transition metals. The solid state structures of some of the group 4 complexes were solved. The titanium, zirconium, hafnium, and vanadium complexes were tested for propylene, 1-hexene, and ethylene/1-octene polymerization activities with methylaluminoxane as co-catalyst. Titanium and zirconium (IV) precatalysts with pyridine-diyl linkers provided mixtures of isotactic and a tactic polypropylene while titanium (IV) precatalysts with benzene-diyl linkers gave atactic polypropylene only.
The hafnium (IV) precatalyst with a pyridine-diyl linker generated moderately isotactic polypropylene. A titanium dibenzyl complex featuring a ligand with two phenolates linked by a benzene-diyl was found to undergo thermal decomposition to give toluene and a cyclometalated dimeric complex. The thermal decomposition followed first order kinetics and was studied at a number of temperatures to determine the activation parameters. Deuterated isotopologs were synthesized to measure the kinetic isotope effects. The complexes with deuterium in the benzyl methylene positions decomposed slower than the protio analogs. Isotopologs of toluene with multiple deuteration positions were observed in the product mixtures. These data are consistent with competing a-abstraction and o-bond metathesis. The protonolysis of bipyrimidine-ligated platinum (II) complexes was explored.
The bipyrimidine platinum dimethyl complex (bpm)PtMe2 was shown to undergo protonation at the metal upon addition of trifluoroacetic acid (tfa) to give a platinum (IV) hydride intermediate which reductively eliminated methane to give (bpm)PtMe(tfa). Using a mixture of deutero- and protio-acid, all isotopologs of methane were observed.
The protonation of (bpm)PtMe(tfa) was less straightforward as no intermediates were found, and CH4 , CH3D, and CH2D2 were observed upon addition of a mixture of deuteroand protio-acid. The protonation of a nitrogen of the bpm ligand was also examined and determined improbable under the present conditions.
The book has been designed to cover the syllabus of this subject. Care has been taken to make the treatment of the subject simple and accessible to the average students.

Preface vii

1. Rate Law and Mechanism 1

Reaction Mechanisms - Derive Rate Laws • Elementa ry Processes or Steps • Deriving Rate Laws from Mechanisms • Reaction Mechanism - Elementary Process • Elementary Reaction Steps - Molecularity • Chain Reactions • Enzy me Kinetics • Rates and Rate Laws

2. Principles of Chemical Dynamics 30

Factors Affecting Reaction Rate; the Rate Law ·Finite Difference Methods of Numerical Analysis • Elementary Processes and Reaction Mechanism • Rate Law and Reaction Mechanism • Requirements for Collision to Lead to Reaction • The Mode of Catalyst Function ·The Production of Sulfuric Acid • Parallel Reactions • Consecutive Reactions • Reversible Reactions • Enzymes as Catalysts ·Mechanisms of Substitution Reactions • The Second-Order Pathway • Substitution in Transition Metal Complexes • Fundamental Substitution Mechanisms

3. Stereochemical Change 101

Atropisomer • Cis-Trans Isomerism • Diazenes • Diastereomer • Naming Conventions • Properties of Enantiomers • Criterion of Enantiomerism • Enantioselective Preparations • Protein Rotamer Libraries

4. Ligand Substitution Reactions 136

Strong Field and Weak Feld Ligands • Crystal Field Theory Analysis • Types of Magnetic Behaviour • Volume Susceptibility • Magnetism, Electricity, and Special Relativity • Diamagnetism • Demonstrations of Diamagnetism • Theory of Diamagnetism • Paramagnetism • Exchange Interactions between Localised Electron Magnetic Moments • Main Group Elements and Orga nic Compounds • Crystal Field Stabilisa tion Energy • Denticity ·Hapticity • Ligand Motifs • Ambidentate Ligand • Conventions • Specialised Ligand Types • Associative Substitution

5. Oxidation-Reduction Reactions 225

Redox • Hydroboration -Oxidation Reaction • Related Reactions • Reducers • Oxidation-Reduction Reactions • Assigning Oxidation Numbers

6. Inorganic Photochemistry 248

Oxidation States • Gneral Chemistry of Oxygen • Reaction of Superoxides • Classes of Pbotochromic Materials

Bibliogrαphy 259

Index 263

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