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Química redox del complejo triple (PNP) Co (I)
Michael J Ingleson1, Maren Pink, Hongjun Fan
1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.
Journal of the American Chemical Society
|March 12, 2008
Resumen
La reacción de los complejos de cobalto con varios reactivos conduce a diversos productos, incluyendo una especie no plana S = 3/2, compuestos de fósforo oxidado e hidratos de cobalto. Los cálculos de DFT ayudaron a racionalizar la formación de complejos de hidruro de cobalto.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Coordinación Química de la Coordinación
- Síntesis Inorgánica y Síntesis Inorgánica.
Sus antecedentes:
- Los complejos de cobalto con ligandos polidentales son cruciales en la catálisis y la ciencia de los materiales.
- Comprender la reactividad de los centros de cobalto con diferentes estados de oxidación es clave para diseñar nuevas moléculas funcionales.
- El ligando (tBu2PCH2SiMe2)2N- (PNP) ofrece un entorno de coordinación único para los centros metálicos.
Objetivo del estudio:
- Para explorar la reactividad de un complejo de cobalto con el ligando PNP.
- Para sintetizar y caracterizar nuevas especies de cobalto con diferentes estados de oxidación y modificaciones de ligando.
- Para investigar la influencia de diferentes reactivos en el centro de cobalto y el andamio del ligando PNP.
Principales métodos:
- Síntesis de complejos de cobalto a través de reacciones con varios reactivos orgánicos e inorgánicos.
- Caracterización de productos utilizando técnicas espectroscópicas y cristalografía de rayos X. Caracterización de productos utilizando técnicas espectroscópicas y cristalografía de rayos X. Caracterización de productos utilizando técnicas espectroscópicas y cristalografía de rayos X. Caracterización de productos utilizando técnicas espectroscópicas y cristalografía de rayos X.
- Cálculos de la Teoría Funcional de Densidad (DFT) para racionalizar las vías de reacción y la estabilidad del producto.
Principales resultados:
- La reacción con el radical galvinoxilo produjo una especie no plana S = 3/2 cobalto (II).
- Las reacciones con haluros de alquilo y yodo produjeron haluros de cobalto (II), mientras que el exceso de yodo condujo a la oxidación del fósforo.
- La hidrogenación con H2 formó un dihidruro de cobalto, y la reacción con PhSiH3 resultó en un complejo de cobalto (V) con nuevos enlaces N/SiPh y P/Si.
- Las reacciones con azidas y dioxígeno/iodosilbenceno llevaron a la extrusión de nitrógeno, modificación de ligando y oxidación de fósforo, respectivamente.
Conclusiones:
- El complejo de cobalto PNP exhibe una rica reactividad, formando diversos productos con estados de oxidación alterados y estructuras de ligandos.
- Las reacciones pueden conducir a resultados inesperados como la oxidación del fósforo y la formación de especies de cobalto de alta valencia.
- Los cálculos de DFT proporcionan información valiosa sobre la viabilidad termodinámica de las transformaciones observadas, en particular para la formación de hidruro.
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