Copper-Catalyzed Asymmetric Borylallylation of Vinyl Arenes.

A copper-catalyzed, enantioselective method for the borylallylation of vinyl arenes is reported. The reaction produces enantioenriched and functionalized organoboron compounds by sequentially incorporating boryl and allyl groups onto the C═C bond of vinyl arenes. Copper-catalyzed borylative coupling of vinyl arenes with allyl phosphates successfully proceeds in a regio- and enantioselective manner in the absence of a palladium cocatalyst.