Kinetics and Mechanism of the Oxidation of 2,3,6-Trimethylphenol with Hydrogen Peroxide in the Presence of Ti-Monosubstituted Polyoxometalates Full article
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Kinetics and Catalysis
ISSN: 0023-1584 , E-ISSN: 1608-3210 |
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| Output data | Year: 2008, Volume: 49, Number: 3, Pages: 371-378 Pages count : 8 DOI: 10.1134/S0023158408030087 | ||
| Tags | MeCN; Catalytic Oxidation; Kinetic Isotope Effect; Phenoxyl Radical; Stoichiometric Reaction | ||
| Authors |
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| Affiliations |
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Funding (2)
| 1 | Russian Foundation for Basic Research | 04-03-32113 |
| 2 | Zamaraev International Charitable Scientific Foundation |
Abstract:
The product composition and reaction kinetics are reported for 2,3,6-trimethylphenol (TMP) oxidation with hydrogen peroxide in acetonitrile catalyzed by a Ti-monosubstituted polyoxometalate (Ti-POM) with a Keggin structure ([Bu4N]4[PTi(OMe)W11O39]) and for the stoichiometric reaction between TMP and the peroxo complex [Bu4N]4[HPTi(O)2W11O39] (I). The main products of the stoichiometric reaction are 2,3,5-trimethyl-1,4-benzoquinone (TMBQ) and 2,2′,3,3′,6,6′-hexamethyl-4,4′-biphenol (BP). The TMBQ yield increases as the TMP/I molar ratio is decreased. The catalytic reaction is first-order with respect to H2O2 and the catalyst and has a variable order (1-0) with respect to TMP. The rate of the reaction increases as the water concentration in the reaction mixture is raised. The stoichiometric reaction is first-order with respect to peroxo complex I and has a variable order (1-0) with respect to TMP. There is no kinetic isotope effect for this reaction (k ArOH/k ArOD = 1). A TMP oxidation mechanism is suggested, which includes the coordination of a TMP molecule and peroxide on a Ti site of the catalyst with the formation of a reactive intermediate. The one-electron oxidation of TMP in this intermediate yields a phenoxyl radical. The subsequent conversions of these ArO° radicals yield the reaction products.
Cite:
Trubitsyna T.A.
, Kholdeeva O.A.
Kinetics and Mechanism of the Oxidation of 2,3,6-Trimethylphenol with Hydrogen Peroxide in the Presence of Ti-Monosubstituted Polyoxometalates
Kinetics and Catalysis. 2008. V.49. N3. P.371-378. DOI: 10.1134/S0023158408030087 WOS Scopus РИНЦ ANCAN OpenAlex
Kinetics and Mechanism of the Oxidation of 2,3,6-Trimethylphenol with Hydrogen Peroxide in the Presence of Ti-Monosubstituted Polyoxometalates
Kinetics and Catalysis. 2008. V.49. N3. P.371-378. DOI: 10.1134/S0023158408030087 WOS Scopus РИНЦ ANCAN OpenAlex
Original:
Трубицына Т.А.
, Холдеева О.А.
Кинетика и механизм окисления 2,3,6-триметилфенола пероксидом водорода в присутствии Ti-монозамещенных полиоксометаллатов
Кинетика и катализ. 2008. Т.49. №3. С.392-399. РИНЦ
Кинетика и механизм окисления 2,3,6-триметилфенола пероксидом водорода в присутствии Ti-монозамещенных полиоксометаллатов
Кинетика и катализ. 2008. Т.49. №3. С.392-399. РИНЦ
Dates:
| Submitted: | May 29, 2007 |
| Published print: | May 1, 2008 |
| Published online: | Jun 14, 2008 |
Identifiers:
| Web of science: | WOS:000256778200008 |
| Scopus: | 2-s2.0-45749133902 |
| Elibrary: | 13587348 |
| Chemical Abstracts: | 2008:727130 |
| Chemical Abstracts (print): | 150:34848 |
| OpenAlex: | W1971110275 |