In this research we prepared about 28 derivatives of five-membered heterocyclic compounds (1,3,4-oxadizoles) in two lines , in the first line we used phenylhydrazide and in the second line we used 4-hydroxy phenylhydrazide as starting material for cyclization, By using eco-friendly efficient synthesis of oxadiazole derivatives through the reaction of aromatic hydrazide with different substituted aromatic aldehydes by grinding them in the presence of catalytical amounts of iodine.