Synthesis of 3-[5-(Substituted Phenyl)-[1,3,4] Oxadiazol-2-yl]-1H-Indazole

In the present investigation, we have reported the synthesis of a series of novel 3-(5-substituted-[1,3,4] oxadiazol-2-yl)-1H-indazole in good yields. 1H-indazole-3-carboxylic acid is converted to their respective esters, which on reaction with hydrazine hydrate afford 1H-indazole-3-carboxylic acid hydrazide. The reaction between 1H-indazole-3-carboxylic acid hydrazide with different substituted benzoic acids in the presence of cyclization agent phosphorus oxychloride gave aimed products in good yields.