Benzethonium Chloride Catalyzed one Pot Synthesis of 2,4,5-Trisubstituted Imidazoles and 1,2,4,5-Tetrasubstituted Imidazoles in Aqueous Ethanol As A Green Solvent

Abstract

A simple, efficient procedure has been developed using N-cationic surfactant namely Benzethonium chloride (BzthCl, 10 mol%) as novel catalyst for the synthesis of 2,4,5-trisubstituted imidazoles by condensation of aldehyde, ammonium acetate and benzil using EtOH-H2O (1:1) as a green solvent at 700C. Same reaction condition was applied successfully to demonstrate the synthesis of various 1,2,4,5-tetrasubstitued imidazoles using aromatic amine as fourth component. The use of benzethonium chloride as a catalyst with dual functionality as surfactant and ionic liquid catalyst is the main novelty of described method. The significant feature of this greener protocol includes high product yields, procedural simplicity and lesser reaction time.