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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Encuadros quirales nanoporosos de metal-metalosaleno para la resolución cinética hidrolítica de los epoxidos
Chengfeng Zhu1, Guozan Yuan, Xu Chen
1School of Chemistry and Chemical Technology and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China.
Journal of the American Chemical Society
|May 2, 2012
Resumen
Las estructuras quirales metal-orgánicas con ligandos salinos de cobalto catalizan de manera eficiente la resolución del epoxido. Este catalizador reciclable logra una alta enantioselectividad (99,5% ee) a través de interacciones bimetálicas cooperativas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La catálisis es la catálisis.
- Química orgánica es la química orgánica.
Sus antecedentes:
- Las estructuras quirales metal-orgánicas (MOF) ofrecen propiedades sintonizables para la catálisis.
- Los complejos salino-metálicos son catalizadores conocidos, pero a menudo sufren de baja reciclabilidad.
- El desarrollo de catalizadores heterogéneos eficientes para la síntesis enantioselectiva es crucial.
Objetivo del estudio:
- Para construir estructuras metal-orgánicas quirales nanoporosas utilizando ligandos quirales salientes.
- Para evaluar el rendimiento catalítico de un MOF basado en salino de cobalto en resolución cinética hidrolítica (HKR).
- Investigar el papel de la estructura de MOF en la mejora de la actividad catalítica y la enantioselectividad.
Principales métodos:
- Síntesis de estructuras metal-orgánicas quirales nanoporosas utilizando ligandos quirales Ni (salina) y Co (salina) funcionalizados con dicarboxilo.
- Aplicación del MOF basado en Co (salina) como catalizador heterogéneo para HKR de epoxidos racémicos.
- Análisis del exceso enantiomérico (ee) utilizando cromatografía quiral.
- Comparación con catalizadores homogéneos de carbonato de sodio.
Principales resultados:
- El MOF basado en Co (salina) demostró una catálisis heterogénea eficiente y reciclable para HKR.
- Se logró una enantioselectividad de hasta un 99,5% ee.
- La estructura de MOF facilitó la disposición densa y la proximidad de las unidades de Co, aumentando las interacciones cooperativas bimetálicas.
- Se observó una mejora de la actividad catalítica y la enantioselectividad en comparación con los análogos homogéneos, particularmente a bajas cargas de catalizador.
Conclusiones:
- Los MOFs basados en sales quirales son catalizadores heterogéneos efectivos para la resolución enantioselectiva del epoxido.
- La arquitectura MOF única promueve efectos bimetálicos cooperativos, aumentando el rendimiento catalítico.
- Este enfoque ofrece una alternativa reciclable y altamente enantioselectiva a los catalizadores homogéneos para la resolución cinética.
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