An environmentally benign attribute for the expeditious synthesis of quinoxaline and its derivatives

A simple, efficient, and environmentally friendly ionic liquid mediated protocol for the synthesis of quinoxaline derivatives using carbonyl substrate and phenylenediamines has been described. A range of ionic liquids were synthesized, characterized via IR, H-1 and C-13 NMR and used as a solvent as well as catalyst for above protocol. The catalytic activities of ILs were evaluated and the relationship between the catalytic activity and acidity was discussed. It was also found that among the all ILs, [Bmim]CF3SO3 was the most effective, eco-friendly and less expensive solvent and catalyst for the above etiquette. This method is of significant value due to the eco-friendly nature of ionic liquid and non usage of separate catalyst to drive the reaction forward. The protocol proves to be efficient and environmentally benign in terms of good to excellent yields, low reaction times, simple work-up, ease of recovery, and reusability of ionic liquid for six times. (C) 2019 Published by Elsevier B.V.