Catalytic asymmetric Michael reactions with enamides as nucleophiles

Article abstract of DOI:10.1002/anie.200702517

(Chemical Equation Presented) 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.