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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
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El emparejamiento iónico en los complejos catiónicos olefina-oro (I)
Daniele Zuccaccia1, Leonardo Belpassi, Francesco Tarantelli
1Dipartimento di Chimica, Università degli Studi di Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy.
Journal of the American Chemical Society
|February 18, 2009
Resumen
El país es el país.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Las interacciones de cationes aniónicos son cruciales en los complejos organometálicos.
- La comprensión de estas interacciones influye en el diseño y la reactividad del catalizador.
Objetivo del estudio:
- Para investigar la orientación relativa de los anión-cationes en los complejos oro-estireno.
- Determinar cómo los ligandos auxiliares afectan el posicionamiento de los counteriones.
Principales métodos:
- Utilizado fluoro-19, protón-1 espectroscopia de efecto de sobrecarga nuclear (19F,1H-HOESY NMR).
- Calculaciones de la Teoría Funcional de Densidad Empleada (DFT) con efectos de disolvente y relativistas.
Principales resultados:
- En [{PPh}3)) Au{4-Me-estireno}]BF{4), el anión BF{4) está cerca de la región de la olefina, frente al grupo fenilo.
- En el [{NHC) Au{4-Me-estireno}]BF{4}, el anión BF{4}{-} está cerca del ligando N-heterocíclico del carbeno (NHC).
- El counterion permanece distante del centro de oro en ambos complejos.
Conclusiones:
- La posición del counterion es sintonizable a través de la elección del ligando auxiliar.
- Esta adaptabilidad permite un mayor control sobre las propiedades y la actividad del catalizador.
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