Lewis Acid Zn(OTf)2 Catalyzed Synthesis ofImidazo[1,2‐a]pyridines by [3+2] Annulation of 2‐Amino Pyridines and Propargylic Alcohols

Abstract

AbstractA novel synthetic protocol for functionalized imidazo[1,2‐a]pyridines were accomplished in one pot by reacting 2‐amino pyridines and propargylic alcohols promoted by lewis acid catalyst. The protocol presented herein, proceeds via Meyer‐Schuster type of rearrangement leading to in situ generation of electron deficient allene and subsequent nucleophilic attack of amines followed by intramolecular cyclization in [3+2] cycloaddition fashion leading to title compounds. Simple reaction conditions, excellent yields and high compatibility are the advantages of this protocol.