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Los catalizadores confinados en poros de marco programados permiten nuevas transformaciones y ajustan la eficiencia y
Tian-You Zhou1, Bernhard Auer1, Seok J Lee1
1MacDiarmid Institute for Advanced Materials and Nanotechnology, Institute of Fundamental Sciences , Massey University , Palmerston North , 4442 New Zealand.
Journal of the American Chemical Society
|January 16, 2019
Resumen
Los investigadores desarrollaron nuevos catalizadores heterogéneos porosos ajustando con precisión el microambiente de las estructuras metal-orgánicas. Estos catalizadores avanzados mejoran la eficiencia y la selectividad de la reacción química, superando a los métodos tradicionales.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Química orgánica
Sus antecedentes:
- El control de las reacciones químicas con catalizadores heterogéneos porosos es un desafío debido a las dificultades para crear sitios activos uniformes y ajustables con precisión.
- Las bolsas catalíticas similares a las enzimas pueden mejorar la eficiencia y la selectividad de la reacción a través de interacciones complementarias con los reactivos.
Objetivo del estudio:
- Desarrollar una nueva familia de catalizadores basados en estructuras metal-orgánicas (MOF) con microambientes catalíticos controlados con precisión.
- Investigar el impacto de la modificación del grupo funcional en la actividad catalítica y la selectividad.
Principales métodos:
- Sintetizó una familia isoreticular de catalizadores utilizando el marco metálico orgánico multicomponente MUF-77.
- Programado el microambiente catalítico mediante la introducción de grupos funcionales (moduladores) a los enlaces orgánicos alejados de la unidad catalítica.
Principales resultados:
- Se logró una mejora simultánea de la reactividad y la selectividad estereocímica en las reacciones aldólicas.
- Reacciones de Henry catalizadas, que no son factibles con análogos homogéneos.
- Se ha demostrado la discriminación entre las vías de reacción en competencia (Henry versus aldol) para un sustrato común.
Conclusiones:
- La funcionalidad de los MOF remotamente desde el sitio catalítico permite un control preciso del microambiente catalítico.
- Este enfoque conduce a un rendimiento catalítico superior, incluida una mayor reactividad, selectividad y control de la vía.
- Los catalizadores MOF desarrollados ofrecen una plataforma prometedora para la síntesis química avanzada.
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