The new route of preparing 1.3,4-oxadiazoles from aromatic acids and semicarbazide hydrochloride in the presence of PPA was described.

• 本文报道了多聚磷酸作用下芳香族羧酸和盐酸氨基脲生成2,5-二取代1,3,4-(口恶)二唑的新方法。