A sustainable synthesis of 3,3-disubstituted oxindoles via CuBr-catalysed capture of carboxylic oxonium ylides with isatylidene malononitrile

We herein reported a sustainable synthesis of 3,3-disubstituted oxindoles via a Michael-type reaction based on the CuBr-catalysed capture of carboxylic oxonium ylides with isatylidene malononitrile. The reaction is characterized by a high atom economy and low economic constraints. The catalyst CuBr could be conveniently recyclized. The products of the reaction were found to be inhibitory against Na ion channels. We expect the reaction to shed the light on synthesis of biologically interesting molecules directed by principles of green chemistry.