Double C─H Phosphorylation of Quinoxalines Under Catalyst-Free Conditions

Abstract

An efficient protocol for synthesis of 2,3-bisphosphoryltetrahydroquinoxalines via double C−H phosphorylation of quinoxalines under catalyst and light-free conditions was developed. The described protocol could deliver a series of bisphosphonylated products in moderate to excellent yields. Moreover, the methodology is highly efficient and tolerant of a number of functional groups such as nitro, ester, carboxy, halogen, and hydroxyl groups. The reported methodology provided an extremely simple and efficient approach to obtain a variety of biphosphorylated quinoxalines as promising pharmaceutical skeletons and ligands in catalysis systems.