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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Mecanismos de la oxidación del agua catalizada por el ion cis,cis-[(bpy) 2Ru(OH2)]2O4+
Hiroshi Yamada1, William F Siems, Tohru Koike
1Department of Chemistry, National Defense Academy, 1-10-20 Hashirimizu, Yokosuka, Kanagawa 239, Japan.
Journal of the American Chemical Society
|August 5, 2004
Resumen
Este estudio revela dos vías para la oxidación del agua catalizada por un complejo de rutenio. Una vía utiliza oxígeno rutenilico y agua solvente, mientras que la otra utiliza exclusivamente moléculas de agua solvente.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- La catálisis es la catálisis.
- Oxidación del agua por oxidación.
Sus antecedentes:
- El complejo de coordinación dimérico cis,cis-[(bpy)(2)Ru(III)(OH2)]2O4+ micro-oxo es un catalizador eficaz para la oxidación del agua.
- La oxidación del agua es un proceso crítico en la conversión de energía y en los sistemas biológicos.
Objetivo del estudio:
- Para dilucidar las vías de reacción y los mecanismos de la oxidación del agua catalizada por el complejo cis,cis-[(bpy)(2)Ru(III)(OH2)]2O4+.
- Investigar el papel del disolvente y el catalizador oxígeno en el proceso de oxidación del agua.
Principales métodos:
- Se utilizó un catalizador etiquetado con (18) O y espectrometría de masas para analizar la distribución isotópica del producto O ((2)).
- Se midieron los parámetros de activación aparente (DeltaH++, DeltaS++) y los efectos del isótopo cinético del deuterio disolvente (KIE).
Principales resultados:
- Se han identificado dos vías de reacción distintas para la formación de O2 .
- La ruta 1 incluye oxígeno rutenilico y agua solvente; la ruta 2 utiliza exclusivamente agua solvente.
- Los efectos de los isótopos cinéticos y los parámetros de activación sugieren la adición de agua para formar hidratos covalentes como un paso crítico.
Conclusiones:
- Los mecanismos propuestos que implican la adición de H2O para formar hidratos covalentes son críticos para ambas vías identificadas.
- La vía 1 implica la adición de H2O a través de átomos de oxígeno rutenilico adyacentes.
- La vía 2 implica la adición de H a un oxígeno rutenilico y la adición de OH a un anillo de bipiridina.
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