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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
Acoplamientos homo y heterodehidro selectivos de fosfinas catalizadas por complejos de fosfido de rodio
1Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|October 19, 2006
Resumen
Los complejos de rodio catalizan las reacciones de deshidrodimerización y deshidroacoplamiento de la fosfina. El estudio identifica las especies de rodio mononuclear como catalizadores activos para la síntesis eficiente de difosfina.
Área de la Ciencia:
- Química organometálica de las sustancias orgánicas.
- La catálisis es la catálisis.
- Química del fósforo en la química del fósforo
Sus antecedentes:
- Los complejos de rodio son catalizadores versátiles en la síntesis orgánica.
- La funcionalización de la fosfina es crucial para el desarrollo de nuevos materiales y ligandos.
- La comprensión de los mecanismos de reacción es clave para el diseño de catalizadores.
Objetivo del estudio:
- Para investigar la reactividad de un complejo específico de rodio con las arilfosfinas.
- Para explorar la actividad catalítica de los complejos de fosfido de rodio en las reacciones de deshidrodimerización.
- Para dilucidar el mecanismo de las reacciones de acoplamiento de fosfina catalizadas por rodio.
Principales métodos:
- Síntesis y caracterización de complejos de rodio.
- Pruebas catalíticas para la deshidrodimerización y el deshidroacoplamiento de las fosfinas.
- Reacciones estequiométricas para aislar los intermediarios.
- Análisis espectroscópico de productos de reacción.
Principales resultados:
- El complejo de rodio 1 reacciona con ArPH2 y Ph2PH para formar complejos de fosfido.
- Los complejos 3a-c y 4 catalizan la deshidrodimerización de las fosfinas a difosfanos.
- El complejo 1 demuestra una alta actividad como catalizador de deshidroacoplamiento, con evidencia de una especie activa mononuclear.
- Se logró un deshidroacoplamiento eficiente con fosfinas estéricamente obstaculizadas.
- El complejo de rodio 1 también cataliza el heteroacoplamiento de fosfinas y tiolos.
Conclusiones:
- El complejo de rodio (dippe) Rh ((eta3-CH2Ph) es un catalizador eficaz para la deshidrodimerización y el deshidroacoplamiento de la fosfina.
- Es probable que las especies de rodio mononucleares sean los catalizadores activos en estas transformaciones.
- El sistema catalítico muestra una amplia aplicabilidad, incluso con sustratos estéricamente exigentes y para reacciones de heteroacoplamiento.
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