A practical metal-free route to 1,2,4,5-tetrasubstituted imidazoles derivatives from the annulation of amidines and β-keto esters

A new practical carbon-nitrogen bond formation reaction of amidines with ethyl acetoacetate to synthesize imidazoles via oxidative cyclization in the presence of bromide. The reactions were occured under mild and metal-free conditions. (C) 2017 The Authors. Published by Elsevier Ltd.