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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Las "reglas de la mayoría" operan en pilas columnares quirales de moléculas simétricas C3
Jeroen van Gestel1, Anja R A Palmans, Bram Titulaer
1Laboratory of Macromolecular and Organic Chemistry, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|April 14, 2005
Resumen
Las moléculas del disco quiral forman hélices dinámicas en solución. Estas estructuras de autoensamblaje exhiben un efecto de "reglas de mayoría", que influyen en la formación de hélices basadas en la orientación molecular predominante.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- C(3) -discos simétricos con partes específicas y colas quirales que se autoensamblan.
- Estudios previos mostraron que estos agregados siguen el principio de "sargentos y soldados" con análogos achirales.
Objetivo del estudio:
- Para investigar el comportamiento de autoensamblaje de las moléculas de disco quiral en disolventes apolares.
- Explorar fenómenos más allá del principio de "sargentos y soldados" en estos sistemas supramoleculares.
Principales métodos:
- Espectroscopia de dicroísmo circular experimental.
- Análisis utilizando un modelo teórico recientemente desarrollado para el ensamblaje supramolecular.
Principales resultados:
- Los agregados de disco quiral exhiben el efecto de "reglas de la mayoría", una nueva observación en sistemas no poliméricos.
- Los datos experimentales se alinean con las predicciones teóricas.
- La penalización por falta de coincidencia para un monómero en un sentido helicoidal no preferido es significativamente menor (0,94 kJ/mol) que la inversión de hélice (7,8 kJ/mol).
Conclusiones:
- El efecto de las "reglas de la mayoría" gobierna la arquitectura supramolecular de estos agregados de disco quiral.
- La baja penalización por falta de coincidencia apoya la estructura supramolecular propuesta.
- Este estudio amplía la comprensión de los principios de autoensamblaje en sistemas no poliméricos.
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