Asymmetric Conjugate Reduction of 3,3-Diarylacrylonitriles

Significance

The report represents an important extension to a reaction recently disclosed by the same group (Angew. Chem. Int. Ed. 2006, 45, 2785). The previous communication described addition to related conjugated systems flanked with small alkyl groups instead of the Ar group shown in 1. The authors show that the copper-catalyzed conjugate hydride addition occurs with excellent enantiotopic selectivity even in the absence of large steric difference between the aryl substituents of 1.