Cooperative Ni/Cu-Catalyzed Asymmetric Propargylic Alkylation of Aldimine Esters.

A novel Ni/Cu dual catalysis gives rise to fundamentally new cooperative reactivity and enables the regio- and enantioselective propargylic alkylation reaction. A diverse set of α-quaternary propargylated amino ester derivatives were synthesized in good yields with excellent enantioselectivity (up to 99 % ee). This work highlights the power of cooperative catalysis, which can be expected to have broad implications in homogeneous catalysis beyond the highly valuable synthetic intermediates.