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Formación controlada del molde de metal de los macrociclos [11]ane-P2C(NHC)
Oliver Kaufhold1, Andreas Stasch, Tania Pape
1Institut fur Anorganische and Analytische Chemie, Universitat Munster, Corrensstrausse 36, D-48149 Munster, Germany.
Journal of the American Chemical Society
|December 11, 2008
Resumen
Este estudio explora la síntesis de los macrociclos N-heterocíclicos carbeno-difosfina utilizando reacciones asistidas por plantilla metálica. Los investigadores crearon con éxito nuevos complejos macrocíclicos con tungsteno y manganeso, caracterizados por la cristalografía de rayos X.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Coordinación Química de la Coordinación
- Química sintética de la química sintética.
Sus antecedentes:
- Los macrociclos N-heterocíclicos carbeno-difosfina son de interés debido a sus propiedades estructurales y electrónicas únicas.
- La ciclización asistida por plantilla metálica ofrece una vía para construir complejas arquitecturas macrocíclicas.
Objetivo del estudio:
- Explorar la síntesis de los macrociclos N-heterocíclicos carbenodifosfina a través de la ciclización asistida por plantilla metálica.
- Investigar la reactividad de los ligandos funcionalizados de carbenos y difosfinas en formación compleja con tungsteno y manganeso.
- Para caracterizar los complejos metálicos y productos intermedios resultantes.
Principales métodos:
- Síntesis de complejos de tungsteno y manganeso con ligandos de carbenos funcionalizados con NH, NH.
- Reacciones de ciclización asistidas por plantilla metálica que involucran ligandos de difosfina con sustituyentes reactivos de fluoro.
- El ataque nucleófilo y las reacciones de desplazamiento intramolecular para la formación de macrociclos.
- Caracterización mediante el uso de métodos espectroscópicos (NMR, IR, espectrometría de masas) y cristalografía de rayos X.
Principales resultados:
- Síntesis exitosa de complejos de tungsteno, incluido un tetracarbonilo de tungsteno de difosfina [3] y un complejo de tetracarbonilo de cloro Re(I) [5].
- Formación de los intermediarios tricarbonilo de carbeno-difosfina ([H(2)-6]Cl) y los siguientes complejos macrocíclicos ([8]Cl) a través del desplazamiento nucleófilo del fluoruro.
- Se observó una química análoga con los complejos de manganeso, que producen cationes tricarbonilo de carbeno-difosfina macrocíclicos ([14](+)).
- Estructuras cristalográficas de rayos X determinadas para múltiples complejos clave, confirmando sus arquitecturas moleculares.
Conclusiones:
- La ciclización asistida por plantilla metálica es una estrategia efectiva para sintetizar macrociclos N-heterocíclicos de carbeno-difosfina.
- La reactividad de los ligandos de fosfina sustituidos por fluoro es crucial para la formación del macrociclo a través del ataque nucleófilo.
- El estudio proporciona una ruta sintética robusta y conocimientos estructurales sobre estos nuevos macrociclos organometálicos.
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