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La activación reversible de H2 mediada por borilo en cobalto: hidrogenación catalítica, deshidrogenación y
1Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|October 2, 2013
Resumen
Un nuevo complejo de cobalto (I) -N2 con un ligando bis-fosfino-borilo permite la activación reversible del dihidrógeno. Este sistema muestra potencial para la hidrogenación catalítica de olefinas y la deshidrogenación de amina-borano.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Síntesis Inorgánica y Síntesis Inorgánica.
Sus antecedentes:
- Los complejos de cobalto se investigan para aplicaciones catalíticas.
- El diseño de los ligandos es crucial para ajustar la reactividad.
- Los ligandos que contienen boro ofrecen propiedades electrónicas y estructurales únicas.
Objetivo del estudio:
- Para sintetizar y caracterizar un complejo de cobalto (I) -N2 apoyado por un ligando meridional de bis-fosfino-borilo (PBP).
- Para investigar la reactividad del complejo de cobalto con dihidrógeno y amina-borano.
- Explorar el potencial catalítico del sistema borilo-cobalto en las reacciones de hidrogenación y deshidrogenación.
Principales métodos:
- Síntesis de un complejo de cobalto (I) -N2 utilizando un ligando PBP.
- Reacción del complejo de cobalto con el dihidrógeno para formar una especie de dihidruro.
- Caracterización de productos intermedios y productos mediante métodos espectroscópicos.
- Evaluación de la actividad catalítica en la hidrogenación de las olefinas y la deshidrogenación de las aminas-borano.
Principales resultados:
- Se sintetizó un complejo estable de cobalto ((I) -N2) (2).
- El complejo 2 reacciona reversiblemente con el dihidrógeno para formar un dihidridoboratocobalto dihidruro (3).
- El sistema borilo-cobalto demostró actividad catalítica en la hidrogenación de olefinas y en la deshidrogenación/hidrogenación de transferencia de amina-borano.
Conclusiones:
- El ligando bis-fosfino-borilo facilita la activación reversible del dihidrógeno por el cobalto.
- El sistema borilo-cobalto es una plataforma prometedora para las reacciones de hidrogenación y deshidrogenación catalítica.
- Este trabajo pone de relieve la utilidad de la incorporación de boro en los marcos de ligandos para controlar la reactividad del metal.
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