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El autoensamblaje de los trifenilenos dendronizados en columnas piramidales helicoidales y esferas quirales
Virgil Percec1, Mohammad R Imam, Mihai Peterca
1Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA. percec@sas.upenn.edu
Journal of the American Chemical Society
|March 25, 2009
Resumen
Los investigadores sintetizaron nuevos trifenilenos dendronizados que se autoensamblan en columnas helicoidales y esferas quirales únicas. Este autoensamblaje supramolecular, impulsado por las interacciones donante-aceptante, ofrece nuevas capacidades de programación para materiales avanzados.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
Sus antecedentes:
- Los derivados del trifenileno son conocidos por sus propiedades de autoensamblaje.
- Los dendrones se utilizan con frecuencia para modificar las propiedades moleculares y el comportamiento de autoensamblaje.
- Controlar el autoensamblaje de las moléculas discóticas en arquitecturas complejas sigue siendo un desafío.
Objetivo del estudio:
- Para sintetizar y analizar los trifenilenos funcionalizados con dendrones autoensambladores.
- Para investigar el comportamiento de autoensamblaje de estos nuevos trifenilenos dendronizados.
- Para explorar la formación de nuevas arquitecturas supramoleculares a partir de moléculas discoticas.
Principales métodos:
- Síntesis de 10 trifenilenos funcionalizados con éter bencílico y éter fenilpropílico. dendrones.
- Análisis estructural y retrostructural de los compuestos sintetizados.
- Investigación del autoensamblaje a través de la caracterización estructural de las arquitecturas formadas.
Principales resultados:
- Los trifenilenos dendronizados adoptaron una conformación de corona en lugar de la típica forma discótica.
- El autoensamblaje condujo a la formación de columnas piramidales helicoidales y esferas quirales, nuevas arquitecturas supramoleculares a partir de moléculas discoticas.
- Estas arquitecturas se organizaron en varias redes (hexagonales, rectangulares) y matrices (cúbicas, tetragonales, cuasiperiódicas).
- El sentido helicoidal estaba controlado por los estereocentros y las interacciones donante-aceptante, permitiendo el autoensamblaje programado a través de un efecto de polímero supramolecular.
Conclusiones:
- Los nuevos trifenilenos dendronizados con forma de corona se autoensamblan en columnas piramidal helicoidales y esferas quirales sin precedentes.
- El proceso de autoensamblaje se puede programar con precisión a través del diseño molecular y las interacciones donante-aceptante.
- Este trabajo abre nuevas vías para diseñar estructuras supramoleculares complejas y ordenadas a partir de unidades discoticas.
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