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Conversión catalizada por paladio de triflados de arilo y vinilo a bromuros y cloruros

Xiaoqiang Shen¹, Alan M Hyde, Stephen L Buchwald

¹Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.

Journal of the American Chemical Society

|September 23, 2010

Resumen

Un nuevo método catalizado por el paladio convierte eficientemente los triflados de arilo y vinilo en haluros correspondientes utilizando ligandos especializados de fosfina. Este avance proporciona una ruta versátil para sintetizar varios haluros de arilo, heteroarilo y vinilo con altos rendimientos.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Química organometálica Química orgánica de los metales.

Sus antecedentes:

Las reacciones de acoplamiento cruzado catalizadas por paladio son fundamentales en la síntesis orgánica.
Los haluros de arilo y vinilo son bloques de construcción cruciales para la síntesis de moléculas complejas.
El desarrollo de métodos eficientes para la síntesis de halogenuros sigue siendo un área activa de investigación.

Objetivo del estudio:

Desarrollar un nuevo método catalizado por paladio para la síntesis de haluros de vinilo y de arilo.
Para utilizar dialkylbiaryl ligandos de la fosfina para mejorar la actividad catalítica y la selectividad.
Establecer un protocolo versátil aplicable a una amplia gama de sustratos.

Principales métodos:

Reacción catalizada por el paladio de triflados de arilo y vinilo.
Con el uso de ligandos de dialquilbiarilfosfina.
Optimización de las condiciones de reacción (carga del catalizador, temperatura, disolvente).

Principales resultados:

Conversión exitosa de triflados de arilo y vinilo a haluros de arilo y vinilo (bromuros y cloruros).
Logró rendimientos buenos a excelentes para una amplia gama de haluros de arilo, heteroarilo y vinilo.
Demostró la eficacia de los ligandos de dialquilbiarilfosfina en esta transformación.

Conclusiones:

Se ha establecido un método robusto y eficiente catalizado por paladio para la síntesis de halogenuros.
El protocolo desarrollado ofrece una herramienta valiosa para acceder a diversos compuestos orgánicos halogenados.
Este método expande la utilidad sintética de los precursores triflados en la química orgánica.

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