A mild and facile method for one pot synthesis of 2,5-di-substituted 1,3,4-oxadiazoles at room temperature

2,5-Di-substituted 1,3,4-oxadiazoles 3a-n have been synthesized as a one pot procedure from the reaction of acid hydrazide 1, acyl halides 2 and phosphorus pentoxide in acetonitrile at room temperature. High yield, short reaction time (10–15 min), mild condition, and easy work-up are advantages of this methodology.