Oxidation of atenolol by diperiodatoargentate(III) in aqueous alkaline medium – a multimechanistic reaction

Article type: Research Article

Authors: Jose, Timy P. | Angadi, Mahantesh A. | Salunke, Manjalee S. | Tuwar, Suresh M.

Affiliations: Department of Chemistry, Karnatak Science College, Dharwad-580 001, Karnataka, India

Note: [] Corresponding author. Email: sureshtuwar@yahoo.co.in

Abstract: The kinetics of oxidation of antihypertensive drug, atenolol by diperiodatoargentate(III) (DPA) in a wide range of alkali has been studied spectrophotometrically. In a lower range of [OH−], the periodate had a retarding effect whereas at higher range of [OH−] the rate of reaction was accelerated. In the higher range of [OH−], the periodate had no effect whereas at lower range of [OH−], periodate and product, [Ag(I)] retarded the rate of the reaction. In the entire range of [OH−], the reaction was unit order in [DPA] and fractional order in [ATN]. Mechanisms consistent with the observed kinetic data for both lower and higher ranges of [OH−] were proposed and discussed. The active species of [Ag(III)] was found to be mono periodatoargentate(III) in lower range of [OH−] and dihydroxymonodiperiodatoargentate(III) in the higher range of [OH−]. The hydrolyzed species of atenolol was found to be the active form of atenolol. Mechanisms for both higher and lower range of [OH−] have been proposed. A composite rate law has been derived and verified for different experimental conditions.

Keywords: kinetics, oxidation, atenolol, mechanism, diperiodatoargentate(III)

DOI: 10.1080/10241220802213902

Journal: Main Group Chemistry, vol. 7, no. 2, pp. 109-122, 2008