N‐Heterocyclic Carbene‐Catalyzed Cyclization of Unsaturated Acyl Chlorides and Ketones

Abstract

Abstract A straightforward synthesis of optically active trifluoromethyl dihydropyranones and spirocyclic oxindole‐dihydropyranones has been realized by the chiral N‐heterocyclic carbenes‐catalyzed cyclization of α,β‐unsaturated β‐methylacyl chlorides with activated trifluoromethyl ketones or isatin derivatives.