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Polímeros supramoleculares basados en tiosquaramida: ganancia de aromaticidad en un modo de autoensamblaje conmutado
Victorio Saez Talens1, Joyal Davis1, Chia-Hua Wu2
1Supramolecular and Biomaterials Chemistry, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA, Leiden, The Netherlands.
Journal of the American Chemical Society
|November 16, 2020
Resumen
El aumento de la aromaticidad en las bolaanfilas de squaramide mejora el autoensamblaje. Este estudio revela cómo la sustitución de oxígeno por azufre impacta las propiedades supramoleculares del polímero, ofreciendo ideas para el diseño del monómero.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- Química orgánica
Sus antecedentes:
- El autoensamblaje de monómeros forma polímeros supramoleculares.
- Los factores que impulsan el autoensamblaje se comprenden cada vez más.
- Se ha pasado por alto el papel de la ganancia de aromaticidad en este proceso.
Objetivo del estudio:
- Investigar el efecto de la ganancia de aromaticidad en los bolaanfifilos a base de squaramida durante el autoensamblaje.
- Para explorar dos modos distintos de auto-ensamblaje.
- Comprender cómo las modificaciones estructurales influyen en las características del polímero supramolecular.
Principales métodos:
- Síntesis de bolaanfifilos de oxo y tiosquaramida.
- Experimentos espectroscópicos para analizar el autoensamblaje.
- Métodos computacionales para evaluar la aromaticidad y las interacciones.
Principales resultados:
- La sustitución de oxígeno por azufre alteró la flexibilidad de la fibra y el grado de polimerización.
- Las oxo- y tiosquaramidas formaban distintos arreglos de "cabeza a cola" y "empillados".
- Ambos modos de autoensamblaje condujeron a un aumento de la aromaticidad y a interacciones intermoleculares más fuertes.
Conclusiones:
- El autoensamblaje de los sintones de squaramide aumenta su carácter aromático.
- Tanto las interacciones de enlace de hidrógeno como las de apilamiento contribuyen a esta ganancia de aromaticidad.
- La aromaticidad es un factor relevante en el diseño de monómeros para polímeros supramoleculares.
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