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Published on: June 21, 2017
Adición directa de Michael de alquenos a través de una reacción de funcionalización vinílica C-H mediada por
Chen Zhao1, F Dean Toste, Robert G Bergman
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|June 25, 2011
Resumen
Este estudio introduce una funcionalización directa C-H de alquenos utilizando complejos cobalto-nitrosilo. El método de una sola olla sintetiza eficientemente compuestos cíclicos insaturados, mostrando un potencial catalítico.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Síntesis orgánica La síntesis orgánica.
- La catálisis es la catálisis.
Sus antecedentes:
- La funcionalización directa C-H ofrece una ruta más atómica y económica para moléculas complejas.
- Los complejos cobalto-nitrosilo proporcionan una reactividad única en las transformaciones orgánicas.
- La síntesis eficiente de compuestos cíclicos insaturados sigue siendo un desafío clave en la química orgánica.
Objetivo del estudio:
- Para desarrollar una reacción de funcionalización directa C-H de un solo bote de alquenos.
- Para utilizar los complejos de cobalto-nitrosilo como mediadores para esta transformación.
- Para sintetizar compuestos cíclicos tetra-alquilo-sustituidos, γ,δ-insaturados.
Principales métodos:
- Se empleó un procedimiento de reacción de una sola olla.
- La funcionalización directa de C-H de los alquenos fue mediada por [CpCo (((NO) ((2)) ] (ciclopentadienilcobalt dinitrosil).
- Se realizó la caracterización de todos los intermedios de reacción.
Principales resultados:
- La reacción produjo con éxito compuestos cíclicos tetra-alquil-sustituidos, γ,δ-insaturados.
- Una variedad de aceptores de Michael fueron compatibles con el procedimiento.
- Se lograron buenos rendimientos del producto.
Conclusiones:
- El método de un solo bote desarrollado proporciona una ruta eficiente a valiosos compuestos insaturados cíclicos.
- La reacción demuestra la utilidad de [CpCo(NO)(2) ] en la funcionalización directa C-H.
- Los resultados preliminares indican el potencial de la rotación catalítica, lo que sugiere futuras aplicaciones en la síntesis sostenible.
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