Synthesis of 2,4,5-Triphenyl Imidazole Derivatives Using Diethyl Ammonium Hydrogen Phosphate as Green, Fast and Reusable Catalyst

A simple highly versatile and efficient synthesis of 2,4,5-trisubstituted imidazoles is achieved by three component cyclocondensation of 1,2-dicarbonyl compounds, aldehydes and ammonium acetate as ammonia source in thermal solvent free condition using Brønsted acidic ionic liquid diethyl ammonium hydrogen phosphate as catalyst. The key advantages of this process are cost effectiveness of catalyst, reusability of catalyst, easy work-up and purification of products by non-chromatographic methods, excellent yields and very short time reactions. Multicomponent reactions enjoy an outstanding status in organic and medicinal chemistry for their high degree of atom economy and application in the diversity-oriented convergent synthesis of complex organic molecules from simple and readily available substrates in a single vessel.