Copper-Mediated Enantioselective Substitution Reactions

In the 1952 paper mentioned above [3], Gilman reported on the formation of lithium dimethylcuprate from polymeric methylcopper and methyllithium. These so-called Gilman cuprates were later used for substitution reactions on both saturated [6] and unsaturated [7, 8, 9] substrates. The first example of a cuprate substitution on an allylic acetate (allylic ester) was reported in 1969 [8], while Schlosser reported the corresponding copper-catalyzed reaction between an allylic acetate and a Grignard reagent (Eq. 2) a few years later [10]. 

or lithium or magnesium homocuprates R CuM (M = Li, MgX), are frequently used, but a number of catalytic processes have also been developed. These processes normally utilize a catalytic amount of a copper salt CuY and a stoichiometric amount of an organometallic reagent R M (M = Li, MgX, ZnX, etc.). The leaving groups used include halides, esters, sulfonates, and epoxides, among others. 

Copper-catalyzed asymmetric substitution reactions can be classified into three major types  

From the data available it is clear that diastereoselective reactions of type (1) are very useful for control over absolute stereochemistry, but they require stoichiometric amounts of the chiral auxiliary. Reactions of type (3), on the other hand, have so far 

As discussed in Chapt. 6, copper-mediated diastereoselective addition and substitution reactions are vell studied methods for the construction of chiral centers in organic molecules. The development of copper-mediated enantioselective substitution reactions, ho vever, is still at an early stage. 

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Karlstrom, A. S. E. Backvall, J.-E. Copper-mediated Enantioselective Substitution Reactions. In Modem Organocopper Chemistry Krause, N., Ed. Wiley-VCH Weinheim, 2002 pp 259-288. 

Karlstrom ASE, Backvall JE (2002) In Krause N (ed) Copper-Mediated Enantioselective Substitution Reactions. Modem organocopper chemistry. Wiley, Weinheim, pp 259-288... 

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