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Rhodium ((II) - Catalyzed C-H Functionalization of Electron-Deficient Methyl Groups (Funcionalización C-H catalizada

Liangbing Fu¹, David M Guptill¹, Huw M L Davies¹

¹Department of Chemistry, Emory University , 1515 Dickey Drive, Atlanta, Georgia 30322, United States.

Journal of the American Chemical Society

|April 12, 2016

Resumen

Este estudio introduce la funcionalización C-H enantioselectiva para los grupos metilo con deficiencia de electrones utilizando nuevos catalizadores de dirodio y diazoacetatos. El método proporciona un amplio alcance de sustrato y una alta enantioselectividad, produciendo compuestos 1,6-dicarbonilo versátiles.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

La funcionalización C-H es una estrategia clave en la síntesis orgánica.
El desarrollo de métodos enantioselectivos para los sitios de metilo con deficiencia de electrones sigue siendo un desafío.
Los catalizadores de dirodio son efectivos para las reacciones de transferencia de carbenos.

Objetivo del estudio:

Desarrollar un método de funcionalización C-H enantioselectivo para los sitios metilo con deficiencia de electrones.
Explorar el uso de arildiazoacetatos de 2,2,2-tricloroetil y catalizadores de dirodio en esta transformación.
Demostrar el amplio alcance del sustrato y la alta enantioselectividad del método desarrollado.

Principales métodos:

Se utilizan como precursores el 2,2,2-tricloroetil arildiazoacetato.
Se emplean catalizadores de tetracis (triarilciclopropanocarboxilato) de dirodio para la funcionalización enantioselectiva de C-H.
Investigó la reacción con varios sustratos con deficiencia de electrones.

Principales resultados:

Se ha logrado la funcionalización C-H enantioselectiva de los sitios metilo con deficiencia de electrones.
Demostró un amplio alcance de sustrato para la transformación.
Se obtienen productos de funcionalización C-H con una excelente enantioselectividad.
Derivados de crotonato expuestos que producen compuestos valiosos de 1,6-dicarbonilo.

Conclusiones:

El método desarrollado proporciona una ruta eficiente para la funcionalización C-H enantioselectiva de grupos metilo con déficit de electrones.
Los compuestos 1,6-dicarbonilo resultantes son productos intermedios versátiles para una mayor diversificación química.
Este trabajo amplía el conjunto de herramientas para la síntesis asimétrica a través de la activación de C-H.

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