Nickel/Enamine Cooperative Catalysis Enables Highly Enantioselective Allylic Alkylation of α-Branched Aldehydes

All-carbon quaternary stereocenters constitute a significant portion of natural products and bioactive compounds. Here we disclose a nickel and chiral amine cooperative catalysis to enable a highly enantioselective allylic alkylation reaction between α-branched aldehydes and a wide scope of allyl esters, allowing the all-carbon quaternary stereocenter to be accessed with excellent enantioselectivity (up to 98% ee) and structural diversity. The general synthetic applicability has been showcased by the enantioselective synthesis of key chiral building blocks to access (+)-eptazocine, (−)-aphanorphine, and other two bioactive compounds.