Copper-mediated conjugate reductions

Copper-mediated conjugate reductions of enones and enoates were reported in 1988 by Stryker and co-workers (188). Stryker and Mahoney (189) showed that the reaction could be made catalytic in copper under an atmosphere of hydrogen gas however, under these conditions, overreduction was observed. In 1998, Lipshutz... 

Many of the copper-mediated transformations summarized in the previous sections of this chapter can also be performed efficiently with catalytic amounts of copper salts or reagents. Indeed, some of the copper-catalyzed reactions have been discovered before the development of stoichiometric organocopper reagents. The focus of the last decade has been put on new copper-catalyzed transformations (e.g., conjugate reductions) and in particular on the discovery of chiral copper catalysts for highly enantioselective 1,4-addition and S -substitution reactions of prochiral substrates. 

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