Organocuprate conjugate additions, role

The role of chlorotrimethylsilane (TMSCl) in accelraating organocuprate conjugate additions continues to arouse much discussion. It has been proposed that TMSCl acts as a Lewis acid in complexing the enone. However, high level ab initio calculations have shown that such complexation is only a weak dipole-dipole inteaction, and cannot... 

Group 11 and 12 Reagents. Reviews of the role of organocuprate clusters in organic chemistry and organocuprate conjugate addition chemistry both... 

Copper has long played a dominant role in stoichiometric organometallic reactions in synthesis. Organocuprate mediated conjugate addition reactions are a cornerstone of carbon-carbon bond-forming reactions. Its preeminence has not been overlooked in the search for asymmetric versions of the reaction (134-136). However, the requirement for stoichiometric amounts of the metal has dampened efforts to introduce chirality into this process. 

Conjugate addition of organocuprates to , -unsaturated carbonyl compounds, including ketones, esters, and amides, are accelerated by addition of TMSCl to provide good yields of the 1,4-addition products (eq 31). The effect of additives such as HMPA, DMAP, and TMEDA have also been examined. The role of the TMSCl on 1,2- and 1,4-addition has been explored by several groups, and a recent report has been published by Lipshutz." His results appear to provide evidence that there is an interaction between the cuprate and TMSCl which influences the stereochemical outcome of these reactions. 

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