Selective cyclization of arylnitrones to indolines under external oxidant-free conditions: Dual role of Rh(III) catalyst in the C-H activation and oxygen atom transfer

Abstract

The first example of Rh(III)-catalyzed cyclization of arylnitrones to indolines under external oxidant-free conditions is presented. An intermolecular coupling of arylnitrones with internal alkynes is made possible by the dual role of the Cp∗Rh(III) catalyst mediating both the C-H bond activation and O-atom transfer. Synthetically important and pharmacologically privileged indoline derivatives were obtained in good yields with high diastereoselectivity. © 2015 American Chemical Society