Synthesis and application of polyvinylimidazole-based Br nsted acidic ionic liquidgrafted silica as an efficient heterogeneous catalyst in the preparation ofquinoxaline derivatives

Abstract

Two types of polymer-grafted silica based on polyvinylimidazole Br nsted acidic ionic liquids were preparedand used as new heterogeneous catalysts for the preparation of pharmaceutically important quinoxaline derivatives.These catalysts were characterized by thermogravimetric analysis, FT-IR spectroscopy, and titration. They could berecycled without considerable loss in their catalytic activity. High efficiency of the catalysts along with short reactiontimes, high yields, easy puri cation, recyclability, and simple procedure are among the advantages of these catalyticsystems.