Palladium-catalyzed alkyne insertion and rearrangement reaction to synthesize oxindoles from o-iodonitroheteroarenes and alkynes

Abstract

A novel tandem reaction involving Pd(II)-catalyzed ortho-C–I bond functionalization, O-atom transfer, [1,2]-aryl shift and deoxygenation of o-iodonitroheteroarenes with alkynes for the synthesis of 3,3-disubstituted oxindoles is described. This protocol features excellent functional group tolerance and allows for the preparation of 3,3-disubstituted oxindoles with a quaternary carbon stereocenter using nonsymmetrical 1,2-diarylalkynes. Besides, DCE acts as both a reaction component and a reductant. Furthermore, this method is amenable to gram-scale synthesis.