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Construcción de complejos monofosfino-metálicos en marcos orgánicos covalentes privilegiados basados en difosfina

Zehao Zheng¹, Chen Yuan¹, Meng Sun¹

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, China.

Journal of the American Chemical Society

|March 10, 2023

Resumen

Los catalizadores quirales monofosfina-metálicos inmovilizados en marcos orgánicos covalentes (COF) permiten una hidrogenación asimétrica eficiente. Estos catalizadores heterogéneos privilegiados a base de fosfina ofrecen un excelente rendimiento y reciclabilidad en condiciones suaves.

Área de la Ciencia:

Química organometálica
Ciencias de los materiales
Catálisis

Sus antecedentes:

Los ligandos privilegiados de difosfina forman complejos metálicos estables que son cruciales para la catálisis.
La actividad del catalizador a menudo no está clara debido a la posible reorganización a complejos monofosfina-metálicos.

Objetivo del estudio:

Para construir complejos quirales monofosfina-metal dentro de las estructuras orgánicas covalentes (COF).
Evaluar su eficacia como catalizadores heterogéneos de un solo sitio para la hidrogenación asimétrica.

Principales métodos:

Se han sintetizado COFs homoquirales 2D mediante la condensación de tetraaldehído de MeO-BIPHEP enantiopuro con diaminas.
Preparación de catalizadores de una sola ubicación de Ir/Ru-monofosfina mediante la metalización posintética de los COF.
Los catalizadores probados en la hidrogenación asimétrica de las quinolinas y los β-cetoéster.

Principales resultados:

Se obtiene hasta un 99,9% de exceso enantiomérico en hidrogenación asimétrica.
Se ha demostrado una excelente actividad catalítica y reciclabilidad de los catalizadores soportados por COF.
Reacciones habilitadas bajo presión de hidrógeno ambiente/medio debido a la naturaleza porosa de los COF.

Conclusiones:

Los complejos monofosfino-metálicos de difosfinas son centros activos para la hidrogenación asimétrica.
Desarrolló una nueva estrategia para la preparación de catalizadores heterogéneos privilegiados a base de fosfina.
La inmovilización de COF proporciona una plataforma robusta para el diseño y la aplicación de catalizadores en un solo sitio.

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