A convenient one-pot method for the preparation of substituted 2-amino-1, 3, 4-oxadiazoles has been developed. The method is a significant improvement over previously reported syntheses. Reaction of carboxylic acids with thiosemicarbazides afforded the corresponding oxadiazoles in moderate to good yields. In general, the products precipitated from the reaction mixture, and were collected by filtration. In most of the cases, no chromatographic ...