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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
Pd(II) - catalizado por la activación de C-H / acoplamiento arilo-arilo de los ésteres de fenol
1Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Journal of the American Chemical Society
|December 22, 2009
Resumen
Este estudio introduce una nueva reacción catalizada por el paladio para los ésteres de fenol, permitiendo la activación ortho C-H y el acoplamiento arilo-arilo. Este método ofrece una nueva vía para sintetizar de manera eficiente valiosos derivados del fenol.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
Sus antecedentes:
- La cicloaladación dirigida por nitrógeno está bien establecida.
- La activación del enlace C-H a través de grupos directivos de oxígeno solamente es menos común.
- Los ésteres de fenol no se han explorado ampliamente como sustratos en la cicloaladación.
Objetivo del estudio:
- Informar sobre el primer complejo de cicloaladación derivado de un simple éster fenol.
- Desarrollar un protocolo novedoso y robusto para la activación ortho C-H y el acoplamiento arilo-arilo de ésteres de fenol.
- Para demostrar la utilidad sintética de esta nueva reacción para crear derivados del fenol.
Principales métodos:
- La cristalografía de rayos X se utilizó para caracterizar el nuevo complejo de ciclo-aladación.
- Desarrollo de un sistema de reacción catalizado por paladio para la activación de C-H/acoplamiento arilo-arilo.
- Optimización de las condiciones de reacción para la eficiencia y el alcance del sustrato.
Principales resultados:
- Caracterización del primer complejo de cicloaladación a partir de un simple éster de fenol.
- Establecimiento de un protocolo robusto para la activación ortho C-H y el acoplamiento arilo-arilo de los ésteres de fenol.
- Demostración de la tolerancia de la reacción al aire y a la humedad.
- Síntesis exitosa de varios derivados útiles del fenol.
Conclusiones:
- Este trabajo amplía el alcance de las reacciones de cicloaladación para incluir grupos de dirección basados en oxígeno en los ésteres de fenol.
- Se ha desarrollado un método práctico y eficiente para el acoplamiento orto C-arilo de ésteres de fenol.
- La metodología proporciona una herramienta valiosa para la síntesis de complejos derivados del fenol.
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