Catalyst-free four-component protocol for the synthesis of substituted pyrroles under reusable reaction media

An efficient four-component protocol is described for the synthesis of diversely functionalized pyrroles under catalyst-free condition by using ionic liquid as a reaction media. The developed method is mild, high yielding, and amenable for a variety of amines as well as aldehydes. Moreover the procedure is of environmentally benign nature in which ionic liquid 1-n-butylimidazolium tetrafluoroborate [Hbim]BF4 is used as a reusable and efficient reaction medium without using any additional catalyst or promoter. (C) 2013 Published by Elsevier Ltd.