Silica supported dodecatungstophosphoric acid (DTP/SiO2): An efficient and recyclable heterogeneous catalyst for rapid synthesis of quinoxalines

Abstract

A facile synthesis of quinoxalines by the cyclocondensation of substituted phenacyl bromides with o-pheneylenediamines using silica-supported dodecatungstophosphoric acid (DTP/SiO2) as a recyclable heterogeneous catalyst is unveiled in this research work. This method is practicable due to environmentally benign, easy workup, high yield, less reaction time, low cost, mild reaction condition, and recyclable heterogeneous catalyst. The catalyst can be easily recovered from the reaction mixture only by filtration and reused up to five catalytic cycles without significant loss of catalytic activity and product yield. This leads to making the process more affordable.