Kinetics of the reaction between 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) derived radical cations and phenols

✍ Scribed by A. M. Campos; E. A. Lissi

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 105 KB
• Volume: 29
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/(sici)1097-4601(1997)29:3<219::aid-kin9>3.0.co;2-x

✦ Synopsis

The reaction between the radical cation derived from 2,2Ј-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and phenols follows a kinetic law given by

with stoichiometric coefficients between one and two. The rate constant is almost unrelated to the structure of the phenol, while the number of ABTS radicals scavenged by each phenol molecule increases with para-substitution. These results are explained in terms of a fast, reversible electron transfer ABTSи ϩ ϩ PhOH VJ ABTS ϩ PhO и ϩ H ϩ followed by the self-combination of the phenoxy radicals and/or their reaction with another ABTS derived radical cation. The relative rate of these processes determine the value of the stoichiometric coefficient.