KCS

1,1-diarylalkyl moieties are important units in a number of physiologically active compounds. We have developed an efficient enantioselective conjugate reduction of β,β-diaryl-substituted-α,β-unsaturated nitriles with copper(II)-Josiphos catalyst in the presence of polymethylhydrosiloxane(PMHS) as the stoichiometric reducing agent. We synthesized a range of substrates with bearing sterically similar aryl groups via copper-catalyzed hydroarylation reaction, and successfully reduced them in high yields with excellent enantioselectivity (up to 97% ee).