Convenient synthesis of the 2,5-di-substituted 1,3,4- oxadiazole derivatives under microwave

We have reported some novel 1,3,4-oxadiazole synthesized by conventional method as well as microwave assisted method. The reaction of different substituted cinnamic acid 2a-o with 2-(4chlorophenyl) acetohydrazide by using phosphoric anhydride as catalyst, yielded a series of 2,5-disubstituted 1,3,4-oxadiazole 6a-o. The structures of all synthesized compounds are well characterized by Mass, FT-IR, 1 H NMR, 13 C NMR and elemental analysis. After obtaining experimental data regarding the yield and the time taken for the synthesis by both the methods, conventional and microwave assisted method, it was proved that the microwave assisted method is convenient for synthesis of this type of 2,5-di-substituted 1,3,4-oxadiazole 6a-o.