A sustainable route toward the synthesis of highly substituted imidazole and quinoxaline derivatives using CuO@g‐C3N4 as an efficient and reusable heterogeneous catalyst

Abstract

This work demonstrates the preparation, characterization, and catalytic application of CuO@g‐C3N4 nanoparticles in synthesizing biologically and pharmaceutically important tetrasubstituted imidazole and quinoxaline derivatives. Highly substituted imidazoles of wide functionalities were synthesized in good yields (71%–85%) using EtOH as a solvent under refluxed conditions within 3–4 h. Similarly, a diverse range of quinoxaline derivatives were synthesized, which rendered moderate to good yield (65%–90%) of the products within 5–60 min in solvent‐free reaction conditions. The practical applicability of the developed protocol is shown by performing a gram‐scale reaction of quinoxaline. Furthermore, the reusability of the catalyst was studied up to the fifth consecutive cycle without much significant decrease in the activity of the catalyst. Additionally, the use of cheap metal and supported materials, shorter reaction time, high substrate scope, and easy recyclability of the catalyst are some of the salient features of the developed protocol.