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Trimerización cooperativa del monóxido de carbono mediante borilos de litio y samario
Baoli Wang1, Gen Luo1, Masayoshi Nishiura1
1Organometallic Chemistry Laboratory and RIKEN Center for Sustainable Resource Science, RIKEN , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|October 31, 2017
Resumen
Los complejos moleculares de litio y samario borilo trimerizan cooperativamente el monóxido de carbono (CO), formando un esqueleto único de diborilalenetriolato. Este mecanismo de reacción ofrece nuevos conocimientos sobre la oligomerización del CO y la catálisis industrial.
Área de la Ciencia:
- Química organometálica
- Catálisis
- Química inorgánica
Sus antecedentes:
- La reacción de Fischer-Tropsch, crucial para la conversión del monóxido de carbono (CO) en hidrocarburos y oxigenados, se basa en catalizadores heteromultimetálicos.
- La comprensión de los mecanismos de conversión de CO a nivel molecular en estos catalizadores sigue siendo un desafío importante.
Objetivo del estudio:
- Investigar la trimización cooperativa del monóxido de carbono (CO) utilizando complejos moleculares de litio y borilo de samario.
- Para aclarar el mecanismo de reacción a nivel molecular.
Principales métodos:
- Utilizó la trimización cooperativa de CO por complejos de samario y litio borilo coexistentes.
- Empleó experimentos etiquetados con 13C para rastrear la vía de reacción.
- Realizó estudios computacionales para comprender los detalles mecanicistas.
Principales resultados:
- La trimización selectiva de CO se produjo en presencia de complejos de litio y samario borilo, dando lugar a un esqueleto de diborilalenetriolato.
- El mecanismo de reacción implica el acoplamiento de una especie de oxicarbeno borílico de samario con una especie de cetenolato de litio.
- Ni el litio ni los compuestos de borilo de samario por sí solos facilitaron esta trimización del CO.
Conclusiones:
- Se ha demostrado una comprensión sin precedentes de la oligomerización del CO promovida por componentes heteromultimetálicos.
- Los resultados pueden mejorar la comprensión del proceso industrial Fischer-Tropsch.
- Proporciona una base para el diseño de nuevos catalizadores para la conversión de CO.
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