Аннотация
Citrate complexes of niobium(V) formed in the interaction of [Nb 6 O 19 ] 8− hexaniobate with citric acid are used for transferring the {NbO} 3+ niobium group to the pseudo-trilacunary [α-B-As III W 9 O 33 ] 9− anion with the formation of sandwich-type [(AsW 9 O 33 ) 2 (NbO) 3 (H 2 O)] 9− complexes. Slow evaporation of the reaction mixture in the presence of dimethylammonium chloride yields crystalline product (NMe 2 H 2 ) 9 [(AsW 9 O 33 ) 2 (NbO) 3 (H 2 O)]·44H 2 O (1) whose structure is determined by single crystal XRD. When the (NBu 4 ) + salt (obtained by the exchange reaction between 1 and tetrabutylammonium bromide) of [(AsW 9 O 33 ) 2 (NbO) 3 (H 2 O)] 9− is dissolved in DMF, As 3+ is oxidized to As 5+ with the formation of a mixture of the Keggin-type [AsW 11 NbO 40 ] 4− and [AsW 10 Nb 2 O 40 ] 5− anions. In an aqueous solution 1 is oxidized by hydrogen peroxide with the formation of a mixture of Keggin anions with different numbers of niobium atoms in the structure.
Язык оригинала | английский |
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Страницы (с-по) | 623-629 |
Число страниц | 7 |
Журнал | Journal of Structural Chemistry |
Том | 60 |
Номер выпуска | 4 |
DOI | |
Состояние | Опубликовано - 1 апр 2019 |