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Ruptura de simetría amplificable en agregados de moléculas helicoidales vibratorias
Fang Wang1, Fuwei Gan1, Chengshuo Shen1
1School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China.
Journal of the American Chemical Society
|September 7, 2020
Resumen
Los aza[4]helicenos achirales rompen espontáneamente la simetría durante el autoensamblaje, formando agregados quirales. Este proceso amplifica la quiralidad y conduce a materiales con prominente luminiscencia polarizada circularmente.
Área de la Ciencia:
- Química supramolecular
- Ciencia de los materiales orgánicos
- Fotónica quiral
Sus antecedentes:
- La ruptura de simetría en las moléculas achirales es crucial para comprender la homociralidad molecular.
- El desarrollo de materiales quirales avanzados a partir de precursores simples sigue siendo un desafío significativo.
Objetivo del estudio:
- Para investigar un modo único de ruptura de simetría espontánea en agregados de aza[4]heliceno achiral.
- Explorar el camino de la amplificación quiral y la evolución de la actividad óptica en estos sistemas.
- Demostrar una nueva ruta para crear materiales ópticamente activos a partir de moléculas helicoidales.
Principales métodos:
- Autoensamblaje de las aza[4]helicenas acirales.
- Análisis de la formación de agregados y la evolución del sesgo quiral.
- Caracterización de la luminiscencia circularmente polarizada (CPL).
Principales resultados:
- Los aza[4]helicenos achirales forman agregados quirales con un sesgo inicial de isómero P/M.
- El desequilibrio quiral se amplifica a través de cambios conformacionales que favorecen el apilamiento estable de π-π.
- La transformación dinámica P/M impulsa la evolución de la actividad óptica y la curación de la quiralidad.
- Los agregados exhiben una luminiscencia circularmente polarizada prominente con un alto factor de disimetría.
Conclusiones:
- Se demuestra una nueva vía para la ruptura espontánea de la simetría quiral en moléculas helicoidales achirales.
- El proceso de autoensamblaje permite la amplificación y la curación de la quiralidad.
- Este trabajo ofrece una nueva estrategia para el diseño de materiales ópticamente activos a partir de precursores acirales.
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