Highly efficient one-pot synthesis of trisubstituted imidazoles under catalyst-free conditions

Operationally simple, atom economical, and scalable synthesis of 2,4,5-trisubstituted imidazoles from benzil, aldehydes, and ammonium acetate is shown to proceed readily in methanol with high yield. The scope of the reaction is quite broad; a variety of aromatic and aliphatic activated and unactivated aldehydes have all been shown to be viable substrates for this reaction. Excellent yields and purity were obtained by washing the products with hot ethanol.