Pd/Cu Synergistic Catalysis for Difluorocarbene-Mediated Synthesis of Carbamoyl-Substituted Oxindoles.
Abstract
A palladium-catalyzed tandem Heck cyclization of N-(2-iodoaryl)acrylamides with N-methylanilines and ClCF2COONa has been developed for the synthesis of carbamoyl-substituted oxindoles bearing an all-carbon quaternary stereocenter, wherein difluorocarbene serves as the carbonyl source. This method operates under mild conditions, exhibits a broad substrate scope, and features operationally simple and safe procedures. Moreover, it expands the synthetic utility of difluorocarbene-involved domino Heck cyclizations and enables the efficient construction of diverse amide-functionalized molecular architectures containing an all-carbon quaternary center.