Kinetic determinations of accurate relative oxidation potentials of amines with reactive radical cations

Ian Gould, Zofia M. Wosinska, Samir Farid

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

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 thermodynamically meaningful oxidation potentials, Eox. In a previous study on amines with radical cations that underwent rapid decarboxylation, we estimated E ox 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.

Original languageEnglish (US)
Pages (from-to)104-109
Number of pages6
JournalPhotochemistry and Photobiology
Volume82
Issue number1
DOIs
StatePublished - Jan 2006

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Amines
Cations
amines
Decarboxylation
Photolysis
cations
Oxidation
oxidation
Kinetics
Oxidation-Reduction
kinetics
Lasers
decarboxylation
Cyclic voltammetry
Thermodynamics
flash
photolysis
Electrochemical oxidation
irreversible processes
Organic compounds

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Biochemistry
  • Biophysics

Cite this

Kinetic determinations of accurate relative oxidation potentials of amines with reactive radical cations. / Gould, Ian; Wosinska, Zofia M.; Farid, Samir.

In: Photochemistry and Photobiology, Vol. 82, No. 1, 01.2006, p. 104-109.

Research output: Contribution to journalArticle

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