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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Funcionalización basada en la topología de marcos orgánicos metálicos robustos basados en quiral Zr para la
Hong Jiang1, Wenqiang Zhang1, Xing Kang1
1School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Journal of the American Chemical Society
|May 5, 2020
Resumen
Desarrollamos marcos metálicos orgánicos estables basados en zirconio quiral (MOF) para apoyar a los catalizadores de iridio para una hidrogenación asimétrica eficiente. La topología MOF dicta el rendimiento catalítico, ofreciendo una nueva estrategia para la catálisis heterogénea.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Química orgánica
Sus antecedentes:
- El desarrollo de catalizadores con soporte robusto es crucial para la síntesis ecológica de productos químicos finos y farmacéuticos.
- Las estructuras quirales metal-orgánicas (MOF) ofrecen estructuras sintonizables para soportar catalizadores metálicos.
- Los MOF a base de zirconio (Zr) son prometedores debido a su estabilidad y versatilidad sintética.
Objetivo del estudio:
- Diseñar y sintetizar MOFs quirales estables basados en Zr con topologías variables.
- Investigar el rendimiento catalítico asimétrico dependiente de la estructura de la red de los complejos de iridio (Ir) soportados.
- Avanzar en la catálisis asimétrica heterogénea utilizando soportes MOF estables.
Principales métodos:
- Se emplearon estrategias de síntesis modulada y expansión isoreticular para construir cinco Zr-MOF quirales.
- Los Zr-MOF se caracterizaron por su estabilidad química en diversas soluciones acuosas.
- Se utilizó una modificación post-sintética para incorporar catalizadores de iridio-fosforo en los MOF.
Principales resultados:
- Dos MOFs quirales con una topología * flu *, con jaulas abiertas, catalizaron eficientemente la hidrogenación de ésteres de ácido α-dehidroamino con un exceso enantiomérico de hasta el 98% (ee).
- Tres MOFs quirales con una topología *ith*, con pequeñas jaulas, no pudieron soportar eficazmente el catalizador de iridio.
- La incorporación de catalizadores de Ir-fosforo en Zr-MOFs mejoró la estabilidad, durabilidad y estereoselectividad.
Conclusiones:
- Los Zr-MOF quirales pueden servir como soportes altamente estables para catalizadores metálicos labiles en la catálisis asimétrica heterogénea.
- La topología del marco MOF influye significativamente en la actividad catalítica y la selectividad.
- Este estudio proporciona información sobre el diseño de centros quirales altamente activos basados en la topología de marco para aplicaciones catalíticas avanzadas.
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