Enantioselective α-Arylation of Cyclic β-Ketoamides with a Quinone Monoimine

摘要

A facile and direct method for the construction of enantioenriched α-arylated quaternary β-ketoamides was developed. By employing a chiral bifunctional thiourea-tertiary amine as catalyst, enantioselective α-arylation of cyclic β-ketoamides with a quinone monoimine proceeded smoothly to afford various α-arylated quaternary β-ketoamides in good yields (up to 97%) with moderate to good enantioselectivities (up to 85% ee). Generally, benzo six-membered cyclic b-ketoamides exhibited better enantioselection than benzo five-membered cyclic β-ketoamides.