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Cargas moduladoras de sitios duales en marcos metálico-orgánicos multivariados para aumentar la epoxidación aeróbica
Hanlin Liu1,2, Wei Liu1,2, Guangxin Xue1
1CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
Journal of the American Chemical Society
|May 10, 2023
Resumen
En el presente estudio se introducen sitios únicos de Cu (I) en un marco metálico-orgánico (CuCo-MOF-74) para la epoxidación selectiva de alquenos utilizando aire. Este catalizador logra una alta selectividad y estabilidad de óxido de estireno, superando los desafíos en la funcionalización de alquenos.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Química orgánica
Sus antecedentes:
- La epoxidación aeróbica selectiva de alquenos es crucial para las aplicaciones industriales.
- Lograr una alta selectividad y evitar reacciones secundarias como la escisión de enlaces CC sigue siendo un desafío significativo.
Objetivo del estudio:
- Desarrollar un nuevo sistema catalítico para la epoxidación aeróbica altamente selectiva de alquenos.
- Para fabricar e investigar el rendimiento de Cu (I) en sitios individuales dentro de un marco metálico-orgánico multivariado (CuCo-MOF-74).
Principales métodos:
- Síntesis solvotermal de CuCo-MOF-74 con reducción parcial del Cu (II) al Cu (I).
- Caracterización de las localizaciones individuales de Cu (I), Cu (II) y Co (II) en el marco.
- Prueba de la actividad catalítica y la selectividad de la epoxidación del estireno utilizando el aire como oxidante.
- Realizar experimentos de contraste y cálculos teóricos para aclarar el mecanismo catalítico.
Principales resultados:
- CuCo-MOF-74 demostró una excelente selectividad para el óxido de estireno (87,6%) en una alta conversión de estireno.
- El catalizador exhibió una mayor selectividad en comparación con el Co-MOF-74 y una buena estabilidad catalítica.
- Los cálculos teóricos indicaron que los sitios Cu ((I) promueven la activación de O2 en los sitios duales Co ((II) y Cu ((I), mejorando la selectividad de la epoxidación.
- El catalizador también mostró una excelente selectividad para la epoxidación de otros alquenos.
Conclusiones:
- La incorporación de Cu(I) en sitios individuales en CuCo-MOF-74 mejora significativamente la selectividad de la epoxidación aeróbica.
- El efecto sinérgico entre los sitios Cu (I) y Co (II) es clave para activar el oxígeno y promover la reacción deseada.
- Este enfoque ofrece una estrategia prometedora para la fabricación de catalizadores eficientes para la epoxidación de alquenos en otras estructuras metal-orgánicas.
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