Synthesis of 1,2,4,5-Tetrasubstituted imidazoles using sulfuric acid ([3-(3-Silicapropyl)sulfanyl]propyl]ester as a recyclable solid acid

Article abstract of DOI:10.1002/jhet.847

Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl]ester (SASPSPE) is used as a recyclable catalyst for the synthesis of 1,2,4,5-tetrasubstituted imidazoles. A range of various polysubstituted imidazoles was synthesized via four-component condensation of benzil, aldehydes, amines, and ammonium acetate in the presence of SASPSPE under solvent-free conditions at 140°C. The heterogeneous catalyst was recycled for five runs on the reaction of benzil, 4-methylbenzaldehyde, benzyl amine, and ammonium acetate without losing its catalytic activity.