Sonochemical Hot-spot Assisted One-pot Synthesis of 4-arylmethylidene - 2-phenyl-4H-oxazol-5-ones Using Nano-MgO as an Efficient Catalyst

Twelve 4-arylmethylidene-2-phenyl-4H-oxazol-5-ones were prepared in excellent yield by sonicating a mixture of an araldehyde, hippuric acid and acetic anhydride in the presence of a green heterogeneous NanoMgO as a basic catalyst. The catalytic activity of NanoMgO was found to be higher compared with bulk MgO powder under the same conditions. This method provides several advantages such as short reaction time, high yields, cleaner reaction condition, involves simple and easy workup procedure makes this protocol economically viable.