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Los carbenos como catalizadores para las transformaciones de los complejos organometálicos del hierro
Vincent Lavallo1, Robert H Grubbs
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|November 11, 2009
Resumen
Los carbenos N-heterocíclicos estables (NHC) median nuevas transformaciones organometálicas del hierro. Estas reacciones forman complejos y grupos únicos de hierro, lo que demuestra los NHC.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Grupo Principal Química.
Sus antecedentes:
- Disponibilidad limitada de catalizadores para transformaciones organometálicas sofisticadas.
- Los carbenos N-heterocíclicos (NHC) son especies orgánicas versátiles con potencial en la catálisis.
- El hierro [Fe (COT) 2] es un precursor reactivo del hierro.
Objetivo del estudio:
- Explorar el potencial catalítico de los carbenos N-heterocíclicos (NHC) en las reacciones organometálicas.
- Para investigar la reactividad de bis ((cyclooctatetraene) hierro [Fe ((COT) 2) mediado por NHCs.
- Desarrollar nuevas transformaciones organometálicas catalizadas por especies orgánicas.
Principales métodos:
- Reacciones de bis ((cyclooctatetraene) hierro [Fe ((COT) 2) con varios iniciadores de carbenos N-heterocíclicos (NHC).
- Reacciones estequiométricas para aislar y caracterizar nuevas especies de hierro.
- Reacciones catalíticas para formar grupos de hierro.
Principales resultados:
- Aislamiento de una nueva especie de hierro mixta-valente con centros Fe ((0) y Fe ((I) a través de la reacción estequiométrica.
- Formación de un grupo de tri-hierro, Fe3 ((COT) 3), un análogo de hidrocarburos de Fe3 ((CO) 12 , a través de una reacción catalítica.
- Evidencia de la formación de enlaces metal-metal inducida por NHC como un paso mecánico clave.
Conclusiones:
- Los carbenos N-heterocíclicos estables (NHC) pueden mediar transformaciones organometálicas inusuales a temperatura ambiente.
- Las reacciones mediadas por NHC ofrecen nuevas vías para sintetizar complejos y grupos de hierro únicos.
- Estos hallazgos establecen una base para el desarrollo de futuras transformaciones organometálicas catalizadas por moléculas orgánicas.
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