Direct Catalytic Asymmetric Addition of Alkylnitriles to Aldehydes with Designed Nickel–Carbene Complexes.

A direct catalytic asymmetric addition of acetonitrile to aldehydes that realizes over 90 % ee is the ultimate challenge in alkylnitrile addition chemistry. Herein, we report achieving high enantioselectivity by the strategic use of a sterically demanding NiII pincer carbene complex, which afforded highly enantioenriched β‐hydroxynitriles. This highly atom‐economical process paves the way for exploiting inexpensive acetonitrile as a promising C2 building block in a practical synthetic toolbox for asymmetric catalysis. [ABSTRACT FROM AUTHOR]