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Selección completa de una jaula homo- o hetero-cavitand autoensamblable a través de la coordinación del metal basada
Kenji Kobayashi1, Yoshifumi Yamada, Masamichi Yamanaka
1Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
Journal of the American Chemical Society
|October 28, 2004
Resumen
Los investigadores formaron de forma selectiva jaulas homo- o hetero-cavitand con el uso de la coordinación de los metales. Diferentes ligandos de cavitandos y un conector de paladio se autoensamblaron en estructuras de jaula específicas, lo que demuestra una síntesis controlada a través de la capacidad de coordinación y los factores estéricos.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Coordinación Química de la Coordinación
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los cavitandos son anfitriones moleculares capaces de formar estructuras complejas.
- La coordinación del metal es una herramienta poderosa para dirigir el autoensamblaje.
- El control de la formación de arquitecturas supramoleculares específicas sigue siendo un desafío.
Objetivo del estudio:
- Para investigar la formación selectiva de homo- y hetero-cavitand jaulas utilizando la coordinación del metal.
- Para explorar la influencia de diferentes ligandos de cavitandos y un conector de paladio en el autoensamblaje.
- Comprender los factores que rigen la selectividad de la formación de las jaulas.
Principales métodos:
- Utilizó tetra ((4-piridil) -cavitand (1), tetrakis ((4-piridil) -cavitand (2) y tetrakis ((4-cianofenil) -cavitand (3) como ligandos de cavitandos profundos.
- Empleado como un conector de coordinación de metal.
- Se analizaron los productos de autoensamblaje utilizando 1H RMN y CSI-MS.
Principales resultados:
- Las jaulas de Homo-cavitand {2(2).4[Pd(dppp) ]}8+.8(TfO-) (5) y {2(3).4[Pd(dppp) ]}8+.8(TfO-) (6) se formaron selectivamente a partir de los ligandos 2 o 3, respectivamente, con el conector 4.
- Se observó una mezcla 1:1 de homo-cavitando de las jaulas 5 y 6 cuando se combinaron los ligandos 2 y 3.
- Una jaula de hetero-cavitando {1.3.4[Pd(dppp) ]}8+.8(TfO-) (7) fue autoensamblada exclusivamente a partir de los ligandos 1, 3 y el conector 4.
Conclusiones:
- La formación selectiva de jaulas homo- o hetero-cavitand es posible a través de la coordinación del metal.
- La selectividad está influenciada por la capacidad de coordinación y la demanda estérica de los ligandos cavitandos.
- Este trabajo proporciona información sobre el diseño racional de estructuras supramoleculares complejas.
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