A new and efficient method for the synthesis of 2-N-(aryl)-1,3,4-oxadiazole-2,5-diamine derivatives

摘要

We report a series of cyclic analogues of 2,5-diamino-1,3,4-oxadiazoles which were prepared in a simple and general protocol. This method involves easy cyclisation of N-(aryl)-1,2-hydrazinedicarboxamides and mediated by tosylchloride/pyridine in ethanol (solvent) under a reflux condition (79-80 A degrees C), over a time period of 20 h. We prepared different examples in a higher range of yields (80-98 %) by using this protocol.