Kinetics and Mechanism of meso-Tetraphenyl-porphyriniron (III) Chloride Catalyzed Oxidation of Aniline and Its Substituents by Oxone in Aqueous Acetic Acid Medium
Article first published online: 24 JUL 2013
© 2013 Wiley Periodicals, Inc.
International Journal of Chemical Kinetics
Volume 45, Issue 9, pages 580–587, September 2013
How to Cite
Raja, M. and Karunakaran, K. (2013), Kinetics and Mechanism of meso-Tetraphenyl-porphyriniron (III) Chloride Catalyzed Oxidation of Aniline and Its Substituents by Oxone in Aqueous Acetic Acid Medium. Int. J. Chem. Kinet., 45: 580–587. doi: 10.1002/kin.20795
- Issue published online: 24 JUL 2013
- Article first published online: 24 JUL 2013
- Manuscript Revised: 2 MAR 2013
- Manuscript Accepted: 2 MAR 2013
- Manuscript Revised: 3 JAN 2013
- Manuscript Received: 2 MAY 2012
Metalloporphyrins are present naturally in cytochromes and hemoglobins. Perhaps the most interesting feature of heme-enzymes, such as cytochromes P450, is their ability to perform extremely difficult oxidations with high selectivity. The present work is undertaken with the aspiration of designing the mechanistic studies on meso-tetraphenylporphyriniron(III) chloride catalyzed oxidation of anilines by potassium peroxymonosulfate (oxone) in aqueous acetic acid medium. The study of oxidation with respect to the catalyst reveals that there is degradation of the catalyst. The concentration-protonated aniline (a less reactive species) increases due to the increase in [H+], which inhibits the rate of the reaction. The thermodynamic parameters for the oxidation have been determined and discussed. It confirms the Exner relationship and also the activation parameters to the isokinetic relationships. The oxone oxidation with 12 meta- and para-substituted anilines complies with the isokinetic relationship but not with any of the linear free energy relationships. The solvent interaction plays a major role in governing the reactivity. A suitable mechanism is proposed for this reaction.