Catalytic Asymmetric Michael Reactions with Enamides as Nucleophiles

Under its own steam: No external proton source is required for catalytic turnover in the copper-catalyzed title reaction with alkylidenemalonates, as proton transfer occurs rapidly in an intramolecular manner. The desired 1,5-dicarbonyl adducts were formed in moderate to high yield with high enantioselectivity (see scheme). R1=alkyl; R2=alkyl, aryl; Tf=trifluoromethanesulfonyl.