Simultaneous Dual Cu/Ir Catalysis: Stereodivergent Synthesis of Chiral ?-Lactams with Adjacent Tertiary/Quaternary/Tertiary Stereocenters

A stereodivergent synthesis of chiral beta-lactams with contiguous tertiary/quaternary/tertiary stereocenters has been achieved by a Cu/Ir-catalyzed three-component interrupted Kinugasa allylic alkylation reaction. The two catalysts independently exert high local stereocontrol, providing access to four of the eight possible stereoisomers in high yields with >99% ee. The features of this strategy are the asymmetric simultaneous dual metal-catalyzed cascade reactions with stereoselective coupling of highly transient organometallic intermediates.