Conversion of 3-Substituted 1,2,4-Oxadiazoles in the present of Fe3O4 to symmetric 1,2,4-Oxadiazole

The chemistry of heterocyclic compounds is an important research area in organic chemistry due to their use in pharmaceuticals and their presence in natural products as well as new materials[1].Oxadiazoles are five-membered heterocyclic compounds that occupy a special place due to thegrowing importance of these heterocycles for the design ofbiologically active compounds and for materials construction [2]. Among oxadiazoles 1,2,4-oxadiazole derivatives have gained importance inmedicinal chemistry.Several methods havebeen reported in the literature for the synthesis of 1,2,4- oxadiazoles. In general, synthesis of 1,2,4-oxadiazoles involves first the O-acylation step of an amidoximeby an activated carboxylic acid derivatives, followed by cyclodehydration. It has been found that cyclizationcould be effected by treating an O-acylamidoxime withNaH or NaOEt at room temperature, pyridine withheating [3]. This work we syntheses symmetric oxadiazole with Fe3O4 as an catalyst.