Titanium-Substituted Heteropolytungstates as Model Catalysts for Studying the Mechanisms of Selective Oxidation by Hydrogen Peroxide Full article
Journal |
Kinetics and Catalysis
ISSN: 0023-1584 , E-ISSN: 1608-3210 |
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Output data | Year: 2001, Volume: 42, Number: 2, Pages: 217-222 Pages count : 6 DOI: 10.1023/A:1010465317943 | ||
Tags | Oxidation; Titanium; Hydrogen Peroxide; Catalytic Activity; Complex Formation | ||
Authors |
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Affiliations |
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Funding (1)
1 | Russian Foundation for Basic Research | 96-03-34215 |
Abstract:
The 31P NMR method shows that four forms of titanium(IV)-monosubstituted Keggin-type heteropolytungstate
(Ti–HPA) exist in MeCN: the dimer (Bu4N)7[{PTiW11O39}2OH] (in the abbreviated form, (PW11Ti)2OH or H1), its conjugate base (PW11Ti)2O (1), and two monomers, PW11TiO (2) and PW11TiOH (H2). The ratio between the forms depends on the concentrations of H+and H2O. Dimer H1is produced from 2 in MeCN when H+(1.5 mol) is added, and monomer H2is the key intermediate in this process. The catalytic activity of Ti–HPA in the oxidation of thioethers by H2O2 correlates with their activity in peroxo complex formation and decreases in the order H2> H1> 2. The reaction of 2 with H2O2 in MeCN occurs slowly to form the inactive peroxo complex PW11TiO2(A). The addition of H2O2 to H1 and H2 most likely results in the formation of the active hydroperoxo complex PW11TiOOH (B). Complexes A and B transform into each other when H+ or OH–(1 mol) is added per 1 mol of A or B, respectively. The activity of B toward thioethers in the stoichiometric reaction is proven by 31P NMR and optical spectroscopy.
Cite:
Kholdeeva O.A.
, Maksimovskaya R.I.
, Maksimov G.M.
, Kovaleva L.A.
Titanium-Substituted Heteropolytungstates as Model Catalysts for Studying the Mechanisms of Selective Oxidation by Hydrogen Peroxide
Kinetics and Catalysis. 2001. V.42. N2. P.217-222. DOI: 10.1023/A:1010465317943 WOS Scopus РИНЦ
Titanium-Substituted Heteropolytungstates as Model Catalysts for Studying the Mechanisms of Selective Oxidation by Hydrogen Peroxide
Kinetics and Catalysis. 2001. V.42. N2. P.217-222. DOI: 10.1023/A:1010465317943 WOS Scopus РИНЦ
ArticleLinkType.TRANSLATED_TO_ORIGINAL:
Холдеева О.А.
, Максимовская Р.И.
, Максимов Г.М.
, Ковалева Л.А.
Титанзамещенные гетерополивольфраматы как модельные катализаторы для исследования механизмов селективного окисления пероксидом водорода
Кинетика и катализ. 2001. Т.42. №2. С.242-248. РИНЦ
Титанзамещенные гетерополивольфраматы как модельные катализаторы для исследования механизмов селективного окисления пероксидом водорода
Кинетика и катализ. 2001. Т.42. №2. С.242-248. РИНЦ
Dates:
Submitted: | Jul 20, 2000 |
Published print: | Mar 1, 2001 |
Identifiers:
Web of science | WOS:000168618500011 |
Scopus | 2-s2.0-0009601678 |
Elibrary | 13363266 |
Chemical Abstracts | 2001:378323 |
Chemical Abstracts (print) | 135:137148 |
OpenAlex | W242286011 |