Cascade Strategy for Atmospheric Pressure CO2 Fixation to Cyclic Carbonates via Silver Sulfadiazine and Et4NBr Synergistic Catalysis

Abstract

It is of great significance and challenge for highly efficient catalytic transformation of carbon dioxide into cyclic carbonates especially under low pressure and energy input conditions. In this regard, an efficient silver sulfadiazine/Et4NBr synergistic catalytic system was developed for the three-component cascade reaction of propargylic alcohols, CO2, and vicinal diols. The reaction was performed in the absence of any solvent under atmospheric CO2 pressure to afford splendid yields of cyclic carbonates. The excellent performance was ascribed to the simultaneous activation of hydroxyl group in propargylic alcohols/vicinal diols by silver sulfadiazine and synergistic effect between silver species and bulkier Et4N+ in the procedure of intramolecular nucleophilic cyclization confirmed by control experiments and NMR spectra.