Abstract The kinetics and oxidation of diclofenac sodium (DFS) by diperiodatoargentate (III)(DPA) in alkaline medium at 298 K and at a constant ionic strength of 0.60 mol dm− 3 were studied spectrophotometrically. The oxidation products were [2-(2, 6-dicloro- phynylamino)-phenyl]-methenol and Ag (I), identified by LC-ESI-MS and IR spectral studies. The reaction between DFS and DPA in alkaline medium exhibits 1: 1 stoichiometry. The ...