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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
Un catalizador extremadamente activo para la reacción de acoplamiento cruzado Negishi
Jacqueline E Milne1, Stephen L Buchwald
1Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Journal of the American Chemical Society
|October 8, 2004
Resumen
Un nuevo sistema de catalizador permite una síntesis eficiente de biarilos estéricamente obstaculizados a través del acoplamiento de Negishi. Este método catalizado por paladio funciona con baja carga de catalizador y diversos sustratos, incluidos los heterociclos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Las reacciones de acoplamiento cruzado catalizadas por paladio son cruciales para la formación de enlaces C-C.
- El acoplamiento Negishi, que utiliza reactivos organozinc, es una herramienta poderosa en la síntesis orgánica.
- La síntesis de biarilos estéricamente obstaculizados sigue siendo un desafío debido al obstáculo estérico.
Objetivo del estudio:
- Desarrollar un nuevo sistema de catalizador para el acoplamiento de Negishi catalizado con paladio.
- Para permitir la síntesis eficiente de biarilos tri- y tetra-orto-sustituidos.
- Para investigar la influencia de la estructura del ligando en la actividad del catalizador y el alcance del sustrato.
Principales métodos:
- Desarrollo de un nuevo sistema de catalizador de paladio.
- Aplicación del sistema catalizador al acoplamiento cruzado de reactivos organozinc con haluros de arilo.
- Variación sistemática de las estructuras de ligandos para optimizar el rendimiento del catalizador.
- Evaluación de la eficiencia del catalizador, el alcance del sustrato y la tolerancia a los grupos funcionales.
Principales resultados:
- El nuevo sistema de catalizador preparaba de manera eficiente los biarilos obstaculizados.
- Se logró una catálisis efectiva a baja carga de paladio.
- El sistema demostró un amplio grupo funcional y tolerancia al sustrato heterocíclico.
- La estructura del ligando se correlacionó significativamente con la actividad del catalizador.
Conclusiones:
- Se ha establecido un sistema de catalizador robusto y eficiente para el acoplamiento Negishi.
- Este método proporciona acceso a complejos compuestos de biarilo estéricamente obstaculizados.
- Los hallazgos ofrecen información valiosa sobre el diseño de ligandos para reacciones de acoplamiento cruzado catalizadas por paladio.
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