Pd(ii) pincer type complex catalyzed tandem C–H and N–H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

Abstract

One-pot, tandem C–H and N–H activation of acetanilides with aryl boronic acids to realize functionalized carbazoles was conveniently performed under aerobic conditions using a novel NNO pincer type Pd(II) complex [Pd(L)Cl] (where L = nicotinic acid (phenyl-pyridin-2-yl-methylene)-hydrazide or furan-2-carboxylic acid (phenyl-pyridin-2-yl-methylene)-hydrazide) as a catalyst in neat water and a very low (0.01 mol%) amount of catalyst. It is worth noting that recyclability up to six consecutive runs and column chromatography free isolation of the title heterocycles in an excellent yield are achieved.