KAl (SO4)2.12H2O (Alum): An Efficient Catalyst for Synthesis of SomeBenzimidazoes and Benzoxazoles Derivatives under Microwave Irradiation

An efficient synthesis of some derivatives of benzimidazoles and benzoxazoles by the condensation of 1, 2-phenylenediamine and 2-aminophenol with orthoesters in the presence of KAl (SO4)2.12H2O (Alum) under microwave irradiation is reported. The advantages of this method includes application of an inexpensive and readily available catalyst, short reaction times, easy workup, improved yields, and solvent-free conditions that is considered to be relatively environmentally friendly.