Triarylimidazole redox catalysts: electrochemical analysis and empirical correlations.
J Org Chem
; 78(5): 2104-10, 2013 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-23186059
ABSTRACT
A series of triarylimidazoles was synthesized and characterized electrochemically. The synthetic route is general, providing a pathway to 30 redox mediators that exhibit a > 700 mV range of accessible potentials. Most of the triarylimidazoles display three oxidation peaks where the first redox couple is quasi-reversible. The electronic character of the substituents affects the oxidation potential. This is exemplified by a linear correlation between the first oxidation potential and the sum of the Hammett σ(+) substituent constants, as well as with a series of calculated ionization potentials. We close by putting forward a rule of thumb stating that for a given mediator, the upper limit of accessible potentials can be extended by at least 500 mV beyond the largest recorded value. A rationale, the conditions under which the rule is likely to apply, and an example are provided.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article