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La relación de aspecto de ligandos como un factor decisivo para el autoensamblaje de las jaulas de coordinación
Suzanne M Jansze1, Giacomo Cecot1, Matthew D Wise1
1Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|February 9, 2016
Resumen
La relación de aspecto del ligando controla con precisión la geometría y la composición del ensamblaje metalo-supramolécula. Esto permite la formación predecible de jaulas de coordinación específicas de hierro y paladio, incluidas las estructuras cúbicas, tetraédricas y octaédricas.
Área de la Ciencia:
- Química supramolecular
- Química de coordinación
- Ciencias de los materiales
Sus antecedentes:
- Los conjuntos supramoleculares de metal ofrecen propiedades sintonizables a través del diseño de ligandos.
- El control de la geometría y la composición de estos conjuntos es crucial para aplicaciones avanzadas.
- Los metalloligandos parecidos a varillas son bloques de construcción clave en la construcción de jaulas de coordinación complejas.
Objetivo del estudio:
- Demostrar el control de la geometría y composición de los conjuntos supramoleculares de metal utilizando la relación de aspecto del ligando.
- Investigar la formación de jaulas de coordinación de hierro (II) y paladio (II) con relaciones de aspecto de ligando variables.
- Explorar la influencia de la relación de aspecto del ligando en la autoclasificación de las mezclas dinámicas de jaula.
Principales métodos:
- Síntesis de complejos de clatrocelatos funcionalizados como metalloligandos tipo varilla con diferentes relaciones de aspecto.
- Reacciones de autoensamblaje de estos metalóligandos con iones de hierro (II) y paladio (II).
- Caracterización de las jaulas de coordinación resultantes mediante técnicas de análisis estructural.
Principales resultados:
- Jaulas cúbicas Fe ((II) 8L12 formadas con ligandos de relación de aspecto intermedia; jaulas tetraédricas Fe ((II) 4L6 formadas con ligandos alargados o estrechados.
- La geometría de la jaula de coordinación Pd(II) fue controlada: conjuntos tetraédricos Pd(II) 4L8 con ligandos de alta relación de aspecto y jaulas octaédricas Pd(II) 6L12 con ligandos más anchos.
- La relación de aspecto del ligando influyó en la composición de las mezclas dinámicas de jaula Pd (II), lo que permitió la autoclasificación selectiva.
Conclusiones:
- La relación de aspecto de ligandos es una herramienta poderosa para el control preciso de la arquitectura de ensamblaje supramolecular de metales.
- Este control se extiende tanto a la geometría como a la composición de las jaulas de coordinación.
- Los hallazgos allanan el camino para diseñar estructuras supramoleculares sofisticadas con propiedades a medida.
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