Transition‐Metal‐Free Alkylation of N‐Heterocycles with Nitriles via Heteroarylphosphonium Intermediates

Abstract

AbstractHeteroarylphosphonium salts are easily accessible, versatile intermediates in functionalization of N‐heterocycles. Direct C−C bond formation by net substitution of the phosphine has so far required transition metal catalysts, the use of strongly basic reagents or redox catalysis. Here we describe a C−C bond formation in direct reactions of benzothiazol‐2‐yl‐phosphonium and pyridin‐4‐yl‐phosphonium salts and nitrile anions which, together with the direct synthesis of phosphonium salts from benzothiazoles and pyridines, constitutes an efficient and simple two‐step protocol for C−H functionalization of these heterocycles under mild conditions.