Study of the oxidation of some catechols in the presence of 4-amino-3-thio-1,2,4-triazole by digital simulation of cyclic voltammograms

✍ Scribed by Lida Fotouhi; Solmaz Taghavi Kiani; Davood Nematollahi; Majid M. Heravi

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 176 KB
• Volume: 39
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.20246

✦ Synopsis

Abstract

Electrochemical oxidation of catechol and its derivatives (1a–d) has been studied in the presence of 4‐amino‐3‐thio‐1,2,4‐triazole (3) at various pHs. Some electrochemical techniques such as cyclic voltammetry using the diagnostic criteria derived by Nicholson and Shain for various electrode mechanisms and controlled‐potential coulometry were used. Results indicate the participation of catechols (1a–d) with 3 in an intramolecular cyclization reaction to form the corresponding 1,2,4‐triazino[5,4‐b]‐1,3,4‐thiadiazine derivatives. In various scan rates, based on an electron transfer–chemical reaction–electron transfer–chemical reaction mechanism, the observed homogeneous rate constants (k~obs~) for Michael addition reaction were estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results. The oxidation reaction mechanism of catechols (1a–d) in the presence of 4‐amino‐3‐thio‐1,2,4‐triazole (3) was also studied. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 340–345, 2007