Pd(OAc)2 catalyzed synthesis of 2-aryl- and 2-heteroaryl-benzoxazoles and benzothiazoles in imidazolium ionic liquids (ILs) without additives and with recycling/reuse of the IL

A facile, high yielding, method for the synthesis of a library of 2-aryl- and 2-heteroaryl-benzoxazoles and benzothiazoles from readily available Schiff bases is reported employing catalytic amounts of Pd(OAc)2 in imidazolium ionic liquids (bmim)BF4 and (bmim)PF6 without ligands and/or additives. Simple product isolation and recycling/re-use of the IL are additional advantages of this method.