Cu-Catalyzed Asymmetric Olefinative Conjugate Addition of Dialkylzinc Reagents

The asymmetric olefinative conjugate addition (AOCA) of dialkylzinc reagents is presented. This involves the Cu-catalyzed enantioselective conjugate addition of dialkylzinc reagents to α-phosphonyl acrylonitrile derivatives, which then allows for an olefinative quench with an aldehyde via Horner-Wadsworth-Emmons reaction. This one-pot sequence efficiently produces chiral internal olefins, addressing a common limitation of Cu-catalyzed enantioselective allylic substitutions, which typically only generate terminal alkenes. Various structurally diverse products are obtained with high yields, complete diastereocontrol, and an er of up to 98:2.