SYNTHESIS OF 2,4,5-TRIARYLATED IMIDAZOLES USING CO(ACAC)2

A simple highly versatile and efficient synthesis of 2,4,5-triarylated imidazoles is achieved by three component cyclocondensation of benzyl or benzoin, aldehydes and NH4OAc, as ammonia source using Co(acac)2 as catalyst in ethanol under reflux condition. Moreover, the utility of this protocol is explored conveniently for the one-pot preparation of 2,4,5-triarylated imidazoles in excellent yields, simple work-up and purification of products by recrystallization method. The catalysts can be recycled for the subsequent reactions without any appreciable loss of their efficiency.