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A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Centros cuaternarios de todo el carbono a través de la hidrovinilación asimétrica catalítica. Nuevos enfoques para el
1Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
Journal of the American Chemical Society
|April 28, 2006
Resumen
Este estudio introduce una eficiente hidrovinilación catalizada por níquel de 1-alquilestirenos utilizando etileno. La reacción produce productos valiosos con centros cuaternarios, que muestran excelentes rendimientos y enantioselectividad para otras aplicaciones sintéticas.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Catalización asimétrica por catálisis asimétrica.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La hidrovinilación es una reacción clave para la formación de enlaces C-C.
- Desarrollar sistemas catalíticos eficientes y enantioselectivos sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar una hidrovinilación catalizada por níquel altamente eficiente y enantioselectiva de los 1-alquilestirenos.
- Explorar la utilidad sintética de los productos resultantes.
Principales métodos:
- Se utilizó un catalizador de níquel preparado a partir de [(alil) NiBr]2 y Na+BAr4-.
- Se emplean ligandos de fosforamidita derivados de enantiopuro de binaftoles y 1-metilbenzilaminas.
- Los 1-alquilistirenos reaccionados con el etileno.
Principales resultados:
- Se logró una hidrovinilación eficiente de los 1-alquilestirenos con etileno.
- Los productos obtenidos tienen excelentes rendimientos y altas enantioselectividades.
- Los productos cuentan con un centro cuaternario con un areno y un grupo de vinilo.
Conclusiones:
- El sistema catalítico desarrollado es altamente eficaz para la hidrovinilación enantioselectiva.
- Los productos sirven como versátiles bloques de construcción para futuras transformaciones sintéticas.
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