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La asociación y la disociación impulsadas por el disolvente de los decavanadatos protonados con enlaces de hidrógeno
Tatsuhiro Kojima1, Mark R Antonio, Tomoji Ozeki
1Department of Chemistry and Materials Science, Tokyo Institute of Technology, 2-12-1-H-63 O-okayama, Tokyo 152-8551, Japan.
Journal of the American Chemical Society
|April 29, 2011
Resumen
Los aniones decavanadato forman dímeros enlazados con hidrógeno en soluciones ricas en acetona, que se disocian de forma reversible en monómeros en el 1,4-dioxano. Este comportamiento está controlado por el disolvente.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Química de la Solución Química de la Solución
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los aniones decavanadato ([H{n}V{10}O{28) ]{6}-n{-)) muestran agregación compleja en la solución.
- Comprender su comportamiento en disolventes no acuosos es crucial para controlar su reactividad.
Objetivo del estudio:
- Para investigar la agregación molecular asistida por enlaces de hidrógeno de aniones de decavanadato en mezclas de disolventes no acuosos.
- Para aclarar el papel de las propiedades del disolvente en la conducción de la asociación y disociación de la descavanadata.
Principales métodos:
- Mediciones sistemáticas de dispersión de rayos X de ángulo pequeño (SAXS).
- Protón ((1) H) y Vanadio-51 ((51) V) Espectroscopia de Resonancia Magnética Nuclear (RMN).
- Experimentos realizados con mezclas de acetona y 1,4-dioxano.
Principales resultados:
- Los aniones de decavanadato forman dímeros autoasociados con enlaces de hidrógeno ({[H(3) V(10) O(28) ](2)}(6-)) bajo condiciones ricas en acetona.
- Estos dímeros se disocian en especies monoméricas a medida que aumenta la proporción de 1,4-dioxano.
- El comportamiento de asociación/disociación observado es reversible.
Conclusiones:
- El estado de agregación de los aniones decavanadato es sensible a la composición del disolvente.
- La asociación reversible está impulsada por la naturaleza protofóbica / protofílica de la mezcla de disolventes.
- Este estudio proporciona información sobre la química de la solución de los polioxovanadatos.
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