Theoretical Organometallic Chemistry

This chapter aims to cover theoretical studies on organometallic molecules. Sections 2 and 3 cover the s- and p-block metals including clusters, carbonyls and metal-metal bonded systems containing M-C bonds. Standard abbreviations for computational methods and basis sets are employed. 

Organometallic Chemistry, Volume 30 The Royal Society of Chemistry, 2002 

The mechanism of Bu Li/TMEDA mediated arene ortholithiation has been studied by B3LYP/6-31G optimisations of reactants and proposed transition structures. Activation energies using MeLi as a computational model for Bu Li have been obtained for different proposed mechanisms including transition structures based upon triple ions of the form [RiLi] [Li(TMEDA)2]. It is shown that alkoxy-lithium interactions are of only minor importance. 

The structures of intermediates and the transition state in the enantioselective deprotonation of iV-boc-pyrrolidine with isopropyllithium/(—)-sparteine have been investigated using HF/3-21G and B3P86/6-31G geometry optimisations. An activation enthalpy of ca. 46 kJ mol is obtained for the lowest energy pathway for H atom transfer. 

HF calculations of the structures and vibrational frequencies of monomers and dimers of lithium alkyl carbonates (methyl, ethyl, and propyl carbonate lithium) and lithium alkoxides (lithium methoxide, lithium ethoxide, lithium propoxide, and lithium butoxide) indicate that they adopt dimeric structures. Dimerisation energies of 214 kJ mol for lithium alkyl carbonates and 266 kJ mol for lithium alkoxides are calculated and are found to be approximately independent of the chain length. 

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Recent Developments in Theoretical Organometallic Chemistry. 15, I Redistribution Equilibria of Organometallic Compounds, 6, 171 Redistribution Reactions of Transition Metal Organometallic Complexes, 23, 9S Redistribution Reactions on Silicon Catalyzed by Transition Metal Complexes, 19, 213 Remarkable Features of (7] -Conjugated Diene) zirconocene and -hafnocene Complexes, 24, I Selectivity Control in Nickel-Catalyzed Olefln Oligomerization, 17, lOS Silyl. Germyl, and Stannyl Derivatives of Azenes. N H Part I. Derivatives of Diazene, N,H2, 23, 131... 

Recent Developments in Theoretical Organometallic Chemistry , D. M. P. Mingos,... 

It is quite clear that molecular hydrogen complexes open a new field in experimental and theoretical organometallic chemistry. Only future exploration will show if this new, promising land is merely an island or if it is, on the contrary, an entire continent, open to organometallic chemistry. 

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