Thiamine Hydrochloride: A Highly Efficient Organo-Catalyst for the One-Pot Synthesis of 2, 4, 5-Triaryl Imidazole Derivatives

In this study, we have developed an expeditious and efficient method for the synthesis of 2,4,5-triaryl imidazole derivatives using thiamine hydrochloride as a catalyst. The one-pot, solvent-free-multicomponent reaction of an aromatic/heterocyclic aldehyde with benzyl and ammonium acetate at reflux conditions leads to the formation of title compounds in extremely good yields. This protocol offers several features, such as safe, simple, atom efficient, economical, mild conditions, minimum waste, easy work-up procedures, shorter reaction time (40-45 min), catalyst recyclability, etc. The developed methodology is operationally simple and eco-friendly.