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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
Hierro ((I) en las reacciones de acoplamiento cruzado de Negishi
Christopher J Adams1, Robin B Bedford, Emma Carter
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
Journal of the American Chemical Society
|June 15, 2012
Resumen
Los complejos de hierro (I) son cruciales para las reacciones de acoplamiento cruzado de Negishi. Los investigadores aislaron y caracterizaron los intermediarios clave del hierro, con uno que se muestra prometedor como un catalizador en ciclo para estas importantes reacciones de síntesis orgánica.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Las reacciones de acoplamiento cruzado Negishi son vitales para la formación de enlaces carbono-carbono.
- El papel de las especies de hierro de baja valencia en estas reacciones sigue siendo un área activa de investigación.
Objetivo del estudio:
- Para demostrar la importancia del hierro (I) en las reacciones de acoplamiento cruzado de Negishi.
- Para aislar y caracterizar los intermediarios catalíticamente activos del hierro.
Principales métodos:
- Síntesis y aislamiento de nuevos complejos de hierro: [FeX (dpbz) 2].
- Caracterización mediante cristalografía de rayos X.
- Evaluación de la actividad catalítica en las reacciones de acoplamiento cruzado Negishi.
Principales resultados:
- Aislamiento de complejos de hierro (I) con ligandos variados (4-tolyl, Cl, Br).
- Los datos cristalográficos confirmaron la estructura de los complejos.
- El complejo 8b (bromuro de hierro) exhibió un rendimiento catalítico consistente con un intermediario en el ciclo.
- El complejo 7 (hierro(I) 4-tolyl) parecía ser una especie fuera del ciclo.
Conclusiones:
- El hierro ((I) juega un papel crítico en el ciclo catalítico de las reacciones de acoplamiento cruzado de Negishi.
- Los complejos de hierro aislados proporcionan información sobre los mecanismos de reacción.
- Especies específicas de hierro pueden actuar como catalizadores eficaces en el ciclo.
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