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Hidrosilación altamente enantioselectiva de alquenos catalizada por cobalto
Biao Cheng1, Peng Lu1, Heyi Zhang1
1Department of Chemistry, Zhejiang University , Hangzhou 310058, China.
Journal of the American Chemical Society
|June 28, 2017
Resumen
Un nuevo método catalizado por cobalto sintetiza eficientemente dihidrosilanos quirales a partir de alquenos. Esta hidrosilación enantioselectiva es simple, atómica y tolera varios grupos funcionales.
Área de la Ciencia:
- Química organometálica
- Catálisis asimétrica
- Química orgánica sintética
Sus antecedentes:
- Los dihidrosilanos quirales son valiosos intermedios sintéticos.
- El desarrollo de métodos catalíticos eficientes y enantioselectivos para su síntesis sigue siendo un desafío.
- La hidrosilación de alquenos ofrece una ruta directa a los compuestos que contienen silicio.
Objetivo del estudio:
- Desarrollar una nueva hidrosilación enantioselectiva catalizada por cobalto de alquenos.
- Para lograr una alta selectividad tipo Markovnikov para la síntesis de dihidrosilanos quirales.
- Establecer un protocolo sencillo y económico desde el punto de vista de la operación, utilizando materiales fácilmente disponibles.
Principales métodos:
- Reacción de hidrosilación catalizada por cobalto.
- Alquenos utilizados (arilo y alifático) y una fuente de silicio.
- Condiciones de reacción optimizadas para la enantioselectividad y el rendimiento.
Principales resultados:
- Se ha logrado una síntesis altamente de tipo Markovnikov y enantioselectiva de dihidrosilanos quirales.
- Se ha demostrado una excelente tolerancia al grupo funcional para una amplia gama de alquenos.
- El protocolo es operacionalmente simple, de economía atómica, escalable a escala de gramos, con un alto número de rotación (TON) y una frecuencia de rotación (TOF) de hasta 860 y 1800, respectivamente.
Conclusiones:
- Se ha desarrollado una hidrosilación enantioselectiva práctica y eficiente de alquenos catalizados por cobalto.
- El método proporciona acceso a valiosos dihidrosilanos quirales con alta selectividad y tolerancia de grupo funcional.
- Este protocolo representa un avance significativo en la catálisis asimétrica para compuestos a base de silicio.
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