A Kinetic and Mechanistic Approach for Oxidation of Isoprenaline by Potassium Dichromate
Keywords:
Pharmaceuticals, Kinetics, Oxidation, Aqueous, EnthalpyAbstract
The oxidation of Isoprenaline, a pharmaceutical compound was studied kinetically in an aqueous medium using potassium dichromate as the oxidant using spectrophotometer at 520 nm. The reaction rate was found to be first order with respect to both the substrate and the oxidant while it is independent of acid concentration. Stoichiometric analysis revealed that one mole of potassium dichromate is required to oxidize three moles of Isoprenaline. Initially a complex intermediate i.e. chromate ester is formed in the rate determining step which later oxidized to form the product. The activation parameters like change in enthalpy ?H, change in entropy ?S and Gibbs free energy change ?G, were calculated based on the results. The positive value of enthalpy change indicates the reaction is endothermic while the negative value of change in entropy indicates highly ordered reaction. The reaction product was found Isoprenaline N-oxide which is easy to remove from the aqueous system. The research will be very helpful for the degradation of Isoprenaline in aqueous medium by dichromate in bulk and maintaining the environmental balance.
References
Bailey, N., Carrington, A., Lott, K. A. K., & Symons, M. C. R. 55. Structure and reactivity of the oxyanions of transition metals. Part VIII. Acidities and spectra of protonated oxyanions. Journal of the Chemical Society (Resumed), pp.290–297, 1960.
Chimatadar, S. A., Madawale, S. V., &Nandibewoor, S. T., Mechanism of oxidation of hexamine by quinoliniumdichromate (QDC) in aqueous perchloric acid, 2007.
Feigl, F. (1955). Organic Spot Test Analysis. Analytical Chemistry, 27(8), pp.1315–1318, 2007. https://doi.org/10.1021/ac60104a031
Gupta, K. K. S., & Chakladar, J. K. Kinetics of the chromic acid oxidation of arsenic (III). Journal of the Chemical Society, Dalton Transactions, 2, pp.222–225, 1974.
Hussain, S., Agrawal, B. R., Pakhare, S. B., & Farooqui, M., Kinetic and mechanistic study of oxidation of ester by K2Cr2O7. International Journal of Chemistry Research, pp.8–10, 2011.
Hussain, S., & Hussain, S. Y. (n.d.). Oxidation Of Alcohols By Tetramethylammonium Fluorochromate?: A Kinetic Study, 2016.
Jiménez, M., García-Cánovas, F., García-Carmona, F., Iborra, J. L., & Lozano, J. A., Isoprenaline oxidation by tyrosinase: Intermediates characterization and kinetic study. Biochemistry International, 11(1), pp.51–59, 1985.
Joseph, J., & Nair, T. R. Effect of Substituents on the Kinetics of the Oxidation of Benzyl Chloride Using Acid-Dichromate. Asian Journal of Chemistry, 19(6), 4733, 2007.
Rangappa, K. S., Anitha, N., & Made Gowda, N. M. Mechanistic Investigations Of The Oxidation Of Substituted Phenethyl Alcohols By Manganese(Iii) Sulfate Catalyzed By Ruthenium(Iii) In Acid Solution. Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 31(8), pp.1499–1518, 2001. https://doi.org/10.1081/SIM-100107212
Sasaki, Y., Bjerrum, J., Timm, D., Sim, G. A., Theander, O., & Flood, H. Equilibrium Studies on Polyanions. 9. The First Steps of Acidification of Chromate Ion in 3 M Na (ClO4) Medium at 25 degrees C. Acta Chemica Scandinavica, 16, pp.719–734, 1962.
Waters, W. A. Mechanisms of oxidation by compounds of chromium and manganese. Quarterly Reviews, Chemical Society, 12(4), pp.277–300, 1958.
Downloads
Published
How to Cite
Issue
Section
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors contributing to this journal agree to publish their articles under the Creative Commons Attribution 4.0 International License, allowing third parties to share their work (copy, distribute, transmit) and to adapt it, under the condition that the authors are given credit and that in the event of reuse or distribution, the terms of this license are made clear.
