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Complejos de hierro eneamido de baja valencia para la hidrogenación asimétrica de transferencia de acetofenona sin
Paraskevi O Lagaditis1, Alan J Lough, Robert H Morris
1Department of Chemistry, University of Toronto, Toronto, Ontario, Canada M5S 3H6.
Journal of the American Chemical Society
|June 2, 2011
Resumen
Los investigadores exploraron los complejos de hierro para la catálisis. Un ligando doblemente desprotonado formó un complejo de cinco coordenadas, permitiendo la hidrogenación de transferencia de la acetofenona sin base añadida, mostrando potencial catalítico.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
Sus antecedentes:
- Se investigaron los complejos de hierro (II) previamente reportados con la fórmula general [Fe (CO) (Br) (PNNP) (BPh (4) ].
- Se examinó el papel de la base en la activación de estos complejos.
Objetivo del estudio:
- Para aclarar el papel de la base en la activación de hierro (II) complejos.
- Para sintetizar y caracterizar nuevos complejos de hierro de cinco coordenadas.
- Para evaluar la actividad catalítica de estos complejos en la hidrogenación por transferencia.
Principales métodos:
- Síntesis de complejos de hierro (II).
- Caracterización estructural del complejo de ligando PNNP doblemente desprotonado.
- Hidrogenación por transferencia catalítica de la acetofenona utilizando el isopropanol como fuente de hidrógeno.
Principales resultados:
- Se formó un complejo de hierro ((II) de cinco coordenadas a través de la doble desprotonación del ligando PNNP tetradentado.
- Los nuevos complejos de hierro (II) catalizaban la hidrogenación de transferencia de la acetofenona en ausencia de una base externa.
- Ciertos análogos exhibieron una actividad catalítica significativa.
Conclusiones:
- La base juega un papel crucial en la activación del ligando PNNP en complejos de hierro (II).
- El complejo sintetizado de hierro de cinco coordenadas (II) es catalíticamente activo en la hidrogenación de transferencia.
- Este estudio abre caminos para el desarrollo de nuevos sistemas catalíticos libres de bases.
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