Dichlofenac (2-[(2,6-Dichloroanilino)Phenyl]Acetic Acid) As A Precursor To New Heterocyclic Compounds

A new series of five and six membered ring heterocyclic compounds were synthesized using 2-[(2,6-dichloroanilino) phenyl] acetic acid (Dichlofenac) (1) as starting material. This compound was converted to its ethyl ester derivative (2) via the acid catalyzed esterification. The ester (2) was converted to the hydrazide derivative (3) through its reaction with hydrazine hydrate. The hydrazide (3) was used as precursor to synthesize the heterocycle containing compounds. Moreover, the hydrazide (3) was converted to the thiosemicarbazide derivatives (5-7) by their reaction with isothiacyanate compounds. The compounds (5-7) were converted to five membered ring heterocyclic compounds, such as, 1,3,4-triazols (8, 9, 12, 13), 1,3,4-thiadiazoles (10, 11) and 1,3,4-oxadiazol (14) under the influence of a miscellaneous of reagents. The cabohydrazide (3) was incorporated in to 1,3,4-oxadiazol (4), phthalimido derivative (15), tetrazine compound (17), pyrazolines (18-22) and isocyanate compound (24). All the synthesized compounds were characterized by physical and spectral data.