Copper-Catalyzed Diastereoselective Borylative α-(N-Aryl)aminoalkylation of Vinyl Arenes with Nitrones

A copper-catalyzed three-component coupling of vinyl arenes, bis(pinacolato)diboron, and nitrones has been developed, which offers access to a diverse range of γ-(N-aryl)amino boronates via reductive workup, exhibiting good-to-excellent diastereoselectivities. This new protocol, which can be performed at a gram scale, utilizes nitrones as simple precursors and provides γ-amino boronates having versatile utilities in downstream applications. Additionally, oxidative pathway control allows the selective generation of 3-substituted α,β-unsaturated imines, expanding the synthetic utility of this catalytic system.