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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Las fosfinas que contienen alenos quirales en catálisis asimétrica
Feng Cai1, Xiaotao Pu, Xiangbing Qi
1Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75398-9038, United States.
Journal of the American Chemical Society
|October 7, 2011
Resumen
Los alenos quirales con grupos básicos pueden actuar como ligandos para metales de transición. Un ligando aleno-bisfosfina con rodio permite la adición altamente enantioselectiva de ácidos arilborónicos a los ésteres α-ceto.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Catalización asimétrica por catálisis asimétrica.
Sus antecedentes:
- Los allenos, específicamente los quirales 1,2-dienos, son moléculas orgánicas versátiles.
- El desarrollo de nuevos ligandos es crucial para avanzar en la catálisis de metales de transición.
Objetivo del estudio:
- Demostrar que los alenos añadidos con funcionalidad básica pueden servir como ligandos efectivos para metales de transición.
- Desarrollar y utilizar un ligando de bisfosfina que contenga aleno para la catálisis asimétrica.
Principales métodos:
- Síntesis de un ligando de bisfosfina que contiene aleno.
- Coordinación del ligando al complejo de Rodio (I).
- Aplicación del catalizador resultante en la adición asimétrica de ácidos arilborónicos a los ésteres α-ceto.
- Solución y análisis estructural del estado sólido.
Principales resultados:
- El ligando aleno-bisfosfina se coordinó con éxito con el Rh{I}.
- El complejo Rh (I) catalizó la adición de ácidos arilborónicos a los ésteres α-ceto con alta enantioselectividad.
- El análisis estructural confirmó la coordinación de una olefina del aleno con el centro metálico, formando ligandos bi y tridentados.
Conclusiones:
- Los alénidos con funcionalidad básica son ligandos viables para metales de transición.
- El ligando de aleno-bisfosfina desarrollado es eficaz para promover las adiciones de conjugados altamente enantioselectivos.
- El modo de coordinación del ligando alleno ofrece oportunidades para diseñar nuevos sistemas catalíticos.
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