Although 2, 5-disubstituted-l, 3, 4-oxadiazoles have been prepared by dehydration of 1, 2- diacylhydrazines,'no reference to 2-substituted-1, 3, 4-oxadiazoles of the type represented by I, appears in the literature. These latter compounds have now been made in good yield by the condensation of an aromatic carboxylic acid hydrazide with excess ethyl orthoformate. Extension of this reaction to higher orthoesters has led to the formation of 2- ...
