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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
La eliminación reductora "inducida por oxidación" del dioxígeno de un complejo de eta2-peroxopaladio (II) promovida
Brian V Popp1, Shannon S Stahl
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA.
Journal of the American Chemical Society
|March 2, 2006
Resumen
Este estudio informa el primer desplazamiento asociativo de dioxígeno de un complejo de peroxopalladio (II) utilizando alquenos con déficit de electrones. Esta reacción forma complejos de paladio (((0) -alqueno a través de un mecanismo de sustitución de ligando asociativo.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Mecanismos de reacción Mecanismos de reacción
Sus antecedentes:
- Los complejos de peroxopaladio (II) son intermediarios clave en las reacciones de oxidación.
- La comprensión de los mecanismos de desplazamiento de ligandos es crucial para el diseño del catalizador.
- La reactividad de los alquenos con déficit de electrones con los complejos metálicos es de gran interés.
Objetivo del estudio:
- Informar el primer ejemplo de desplazamiento asociativo de dioxígeno de un complejo de peroxopalladio.
- Para investigar el mecanismo de reacción y la influencia de las propiedades electrónicas de los alquenos.
- Para sintetizar nuevos complejos de paladio ((0)) -alqueno.
Principales métodos:
- Reacción de varios p-X-trans-beta-nitrostirenos con (bc) Pd(eta2-O2) (bc = bathocuproína).
- Caracterización espectroscópica de los complejos palladio-alqueno resultantes.
- Estudios mecanicistas para elucidar la vía de reacción.
Principales resultados:
- Los alquenos con deficiencia de electrones desplazaron cuantitativamente el oxígeno del complejo de peroxopaladio (II).
- La reacción se produce a través de un mecanismo de sustitución de ligando asociativo.
- Las propiedades electrónicas de los alquenos influyen en la vía de reacción, consistente con una eliminación reductiva inducida oxidativamente.
Conclusiones:
- El desplazamiento asociativo del dioxígeno de los complejos de peroxopaladio (II) es factible.
- La reacción ofrece una nueva ruta a los complejos palladio-alqueno.
- Los hallazgos proporcionan información sobre los mecanismos de las reacciones catalizadas por el paladio.
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