Organocuprates conjugate addition reactions

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. 

The many uses of organocuprates have been the subject of numerous reviews,1 3 4 6-10 especially the conjugate addition reaction which has received the most attention1 and is the subject of this discussion. 

J. A. Kozlowski, Organocuprates in the Conjugate Addition Reaction, in Comprehensive Organic Synthesis (B. M. Trost, I. Fleming, Eds.), Vol. 4, 169, Pergamon Press, Oxford, 1991. 

The copper-catalyzed 1,4-addition of Grignard reagents to enones has been described by Kharasch in 1941, that is, one decade before the discovery of Gilman cuprates (1952) and more than two decades before the first use of organocuprates in conjugate addition reactions. Consequently, numerous variations and applications of the method have been reported over the years.3 5,7 7a 23 Not surprisingly, several of the advances made in the last decade with... 

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