Polyethylene glycol embedded tribromide as an efficient and reusable catalyst for the library synthesis of nitrogen containing heterocycles

Potassium tribromide wrapped around polyethylene glycol ({K+PEG400}Br3-) was easily prepared by two step reaction of PEG400 with KBr followed by the addition of molecular bromine to give PEG embedded potassium tribromide as a dark viscous oil. The synthesized material was found to be an efficient, cost effective, environmentally benign and recyclable catalyst for the library synthesis of nitrogen containing heterocyclic compounds via multicomponent coupling reaction. The method offers a set of advantages such as facile synthesis, low cost, recycling ability and high product yields.