Current address: Department of Chemistry, University of Rochester, Rochester, NY 14627-0216, USA.
Kinetic Determinations of Accurate Relative Oxidation Potentials of Amines with Reactive Radical Cations†
Article first published online: 30 APR 2007
Photochemistry and Photobiology
Volume 82, Issue 1, pages 104–109, January 2006
How to Cite
Gould, I. R., Wosinska, Z. M. and Farid, S. (2006), Kinetic Determinations of Accurate Relative Oxidation Potentials of Amines with Reactive Radical Cations. Photochemistry and Photobiology, 82: 104–109. doi: 10.1562/2005-06-14-RA-571
This paper is part of a special issue dedicated to Professor J. C. (Tito) Scaiano on the occasion of his 60th birthday.
- Issue published online: 30 APR 2007
- Article first published online: 30 APR 2007
- Received 14 June 2005; accepted 17 July 2005; published online 1 September 2005
Accurate oxidation potentials for organic compounds are critical for the evaluation of thermodynamic and kinetic properties of their radical cations. Except when using a specialized apparatus, electrochemical oxidation of molecules with reactive radical cations is usually an irreversible process, providing peak potentials, Ep, rather than thermo-dynamically meaningful oxidation potentials, Eox. In a previous study on amines with radical cations that underwent rapid decarboxylation, we estimated Eox by correcting the Ep from cyclic voltammetry with rate constants for decarboxylation obtained using laser flash photolysis. Here we use redox equilibration experiments to determine accurate relative oxidation potentials for the same amines. We also describe an extension of these experiments to show how relative oxidation potentials can be obtained in the absence of equilibrium, from a complete kinetic analysis of the reversible redox kinetics. The results provide support for the previous cyclic voltammetry/laser flash photolysis method for determining oxidation potentials.