Hexazirconium- and Hexahafnium-Containing Tungstoarsenates(III) and Their Oxidation Catalysis Properties
Научная публикация
| Общее |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
Опубликована,
Оригинальность:
Оригинальная
|
| Журнал |
Chemistry - A European Journal
ISSN: 0947-6539
, E-ISSN: 1521-3765
|
| Вых. Данные |
Год: 2010,
Том: 16,
Номер: 39,
Страницы: 11797-11800
Страниц
: 4
DOI:
10.1002/chem.201000786
|
| Ключевые слова |
hafnium, homogeneous catalysis, oxidation, polyoxometalates, zirconium |
| Авторы |
Al-Kadamany Ghada
1
,
Mal Sib Sankar
1,3
,
Milev Borislav
1
,
Donoeva Baira G.
2
,
Maksimovskaya Raisa I.
2
,
Kholdeeva Oxana A.
2
,
Kortz Ulrich
1
|
| Организации |
| 1 |
International University Bremen
|
| 2 |
Институт катализа им. Г.К. Борескова СО РАН
|
| 3 |
University of Ottawa
|
|
Информация о финансировании (4)
|
1
|
Российский фонд фундаментальных исследований
|
09-03-91333
|
|
2
|
International University Bremen
|
|
|
3
|
German Research Foundation
|
KO 2288/9-4
|
|
4
|
Verband der Chemischen Industrie
|
|
In summary, the two novel polyanions [M6O4(OH)4-(H2O)2(CH3COO)5(AsW9O33)2]11 (M=Zr, 1; Hf, 2) contain
an unprecedented octahedral Zr6/Hf6 assembly that is stabilized by two (B-a-AsW9O33) groups and five bridging acetate ligands. Both compounds were characterized by several techniques in the solid state. NMR studies in solution were also conducted on 1 and 2 in H2O/D2O and MeCN solutions, respectively. The spectra suggest C2v symmetry for the polyanions in solution, most likely due to fluxional behavior of the labile acetate groups. The TBA salts of both 1 and 2 revealed high catalytic activity and selectivity in the liquidphase oxidation of organic compounds with aqueous H2O2.
A heterolytic oxidation mechanism is manifested by the high yields of epoxide and diol in the oxidation of cyclohexene.
We plan to perform additional mechanistic studies to better understand the catalytic behavior of 1 and 2, and also
to prepare other carboxylate and perhaps also peroxo derivatives of the title polyanions.