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Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Reducción estequiométrica sin metales del CO en el gas de síntesis
Roman Dobrovetsky1, Douglas W Stephan
1Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario, M5S 3H6 Canada.
Journal of the American Chemical Society
|March 26, 2013
Resumen
Este estudio muestra cómo un compuesto de boro y una fosfina reaccionan con el gas de síntesis (CO y H2) para formar nuevos compuestos heterocíclicos. El calentamiento adicional conduce a la escisión de los enlaces C-O, produciendo un derivado de borano-oxiborato.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química del boro y su química.
- La catálisis de la catálisis.
Sus antecedentes:
- La activación y la transformación de pequeñas moléculas como el monóxido de carbono (CO) son fundamentales para la química sintética.
- Los compuestos de boro, particularmente aquellos con centros de boro con déficit de electrones, se exploran cada vez más por su reactividad única.
- Los ligandos de fosfina juegan un papel crucial en la estabilización de los intermediarios reactivos y la modulación de la actividad catalítica.
Objetivo del estudio:
- Para investigar la reacción de un ácido de Lewis de boro específico, el tris (pentafluorofenil) borano (B (C6F5) 3), con la tri-ter-butilfosfina (tBu3P) en presencia de gas de síntesis (gas de síntesis).
- Para dilucidar la vía de reacción, incluyendo la formación de productos intermedios y los productos finales.
- Explorar el potencial para la escisión de bonos C-O y las transformaciones subsiguientes.
Principales métodos:
- Reacción estequiométrica de B(C6F5)3 y tBu3P (relación 2:1) con el gas de síntesis.
- Caracterización de los intermedios y productos de reacción mediante técnicas espectroscópicas.
- Tratamiento térmico de la mezcla de reacción para inducir nuevas transformaciones.
Principales resultados:
- La reacción reduce estequiométricamente el CO para formar un derivado del formilo.
- Se forma un intermedio epoxi-borato, que captura otra molécula de CO para producir un alkoxiborato heterocíclico.
- El calentamiento del producto conduce a la reacción con H2, lo que resulta en la escisión del enlace C-O y la formación de un derivado de borano-oxiborato.
Conclusiones:
- El estudio demuestra una nueva vía para la transformación de CO mediada por una combinación de un ácido de Lewis fuerte y una fosfina voluminosa.
- La formación de un alkoxiborato heterocíclico y su posterior transformación pone de relieve la versatilidad de los sistemas basados en boro en la activación de moléculas pequeñas.
- La escisión del enlace C-O observada proporciona información sobre las vías reductivas relevantes para la utilización del CO.
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