Autoxidation of 2,6-di- tert-butylphenol catalyzed by 5,10,15,20-tetrakis[4-(diethylmethylammonio)phenyl]porphyrinatocobalt(II) tetraiodide in water

• Published in: Journal of molecular catalysis. A, Chemical Vol. 268; no. 1; pp. 24 - 28
• Main Authors: Hassanein, M., Gerges, S., Abdo, M., EL-Khalafy, S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2007; Elsevier
• Subjects: Catalysis; Cationic cobalt(II) porphyrin complex; Chemistry; Exact sciences and technology; General and physical chemistry; Oxidation of 2,6-di- tert-butylphenol; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Oxidation of 2,6-di- tert-butylphenol; Cationic cobalt(II) porphyrin complex; Catalysis; Water; Catalytic reaction; Nitrogen heterocycle; Cobalt complex; Autoxidation; Oxidation of 2,6-di-tert-butylphenol; Phenols; Benzenic compound; Oxidation; Metalloporphyrin; Cobalt II Complexes
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2006.11.045

Cationic cobalt(II) tetraarylporphyrin 1 has been prepared and was used as an efficient catalyst for autoxidation of 2,6-di- tert-butylphenol. ▪ The cationic cobalt(II) porphyrin complex: 5,10,15,20-tetrakis[4-(diethylmethylammonio)phenyl]porphyrinatocobalt(II) tetraiodide has been found to be an efficient catalyst for the oxidation of 2,6-di- tert-butylphenol by dioxygen in aqueous medium. The oxidation reaction afforded mainly the corresponding diphenoquinone and some of the 2,6-di- tert-butyl-1,4-benzoquinone. The initial rate constant of autoxidation reaction was found to increase with increasing pH from 7.0 to 10.0. The rate of autoxidation reaction showed linear dependence on catalyst concentration and dioxygen pressure. The rate of autoxidation reaction was found to fit a Michealis–Menten kinetic model for saturation of catalyst sites with increasing 2,6-di- tert-butylphenol concentration. The catalyst showed reduced activity in repeat oxidation reactions.