One-pot synthesis of 2-substituted quinoxalines using K10-montmorillonite as heterogeneous catalyst
摘要:
An efficient one-pot synthesis of 2-substituted quinoxalines from 1,2-diamines and phenacyl bromides is developed using K10-montmorillonite (K10 clay) as a catalyst at 50 degrees C in acetonitrile medium. This method offers an easy route for the synthesis of substituted quinoxalines in high yields. A plausible mechanism is proposed in which quinoxalines are formed via dehydration-dehydrohalogenationcyclization sequence. Further, the K10 clay catalyst is recovered by simple filtration and reused six times without any loss in its catalytic activity. (C) 2014 Elsevier Ltd. All rights reserved.