Cu-Catalyzed Asymmetric Olefinative Conjugate Addition of Aryl and Alkenyl Boronic Esters

The asymmetric olefinative conjugate addition (AOCA) has been previously introduced as a telescoped approach for the synthesis of chiral internal olefins with high stereoselectivities. Here, this strategy is extended by the implementation of aryl and alkenyl boronic esters as C(sp2) nucleophiles, thus notably expanding the range of accessible products by the AOCA. A variety of relatively complex chiral products are reported, which were obtained in high yields, diastereoselectivities, and enantioselectivities up to 97:3 er. These include dienes and trienes that are otherwise difficult to access in a single step.