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Borilenos terminales catiónicos por abstracción de haluros: síntesis y caracterización espectroscópica y estructural
Deborah L Coombs1, Simon Aldridge, Cameron Jones
1Department of Chemistry, Cardiff University, P.O. Box 912, Park Place, Cardiff, CF10 3TB UK.
Journal of the American Chemical Society
|June 6, 2003
Resumen
Los investigadores sintetizaron un complejo de hierro borileno terminal catiónico, [Cp*Fe(CO) 2(BMes) ]+, que presenta un nuevo enlace doble hierro-boro. Este descubrimiento avanza en la química organometálica y en el estudio de la unión metal-boro.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química Inorgánica La química inorgánica es la química inorgánica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La exploración de nuevos enlaces metal-boro es crucial para el desarrollo de nuevos sistemas y materiales catalíticos.
- Los complejos de borileno catiónico representan una clase poco estudiada de compuestos con propiedades electrónicas únicas.
Objetivo del estudio:
- Para sintetizar y caracterizar un complejo de borileno terminal catiónico con un enlace doble hierro-boro.
- Investigar las propiedades electrónicas y estructurales de las especies de hierro-borileno recién sintetizadas.
Principales métodos:
- Síntesis del complejo de borileno a través de la abstracción de halogenuro de un precursor de bromoborilo mediante el uso de tetráquido de sodio ((3,5-bis ((trifluorometil) fenil) borato (Na[BAr f4]).
- Caracterización utilizando espectroscopia infrarroja (IR), espectroscopia de resonancia magnética nuclear (RMN), cristalografía de rayos X y cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- Síntesis exitosa del complejo de borileno terminal catiónico [Cp*Fe(CO) 2(BMes) ]+ como su sal [BAr f4]- con un rendimiento aproximado del 50%.
- Los datos espectroscópicos y cristalográficos, respaldados por el análisis de DFT, proporcionan una fuerte evidencia de un discreto enlace doble Fe=B.
Conclusiones:
- El estudio reporta el primer complejo de borileno terminal catiónico estabilizado por un centro de hierro.
- Se confirma la presencia de un enlace doble Fe=B, ampliando la diversidad conocida de enlaces múltiples metal-boro.
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