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Transcripción de la quiralidad desde el marco metálico-orgánico al politiofeno
Takashi Kitao1,2, Yujiro Nagasaka2, Masanobu Karasawa3
1Department of Applied Chemistry, Graduate School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku, Tokyo 113-8656 , Japan.
Journal of the American Chemical Society
|December 3, 2019
Resumen
Las estructuras quirales metal-orgánicas (MOF) confieren quiralidad a los polímeros de politiofeno (PTh) aquirales. Este confinamiento induce una quiralidad estable en PTh, incluso después de la extracción del soporte MOF.
Área de la Ciencia:
- Ciencias de los materiales
- Química de los polímeros
- La cristalografía
Sus antecedentes:
- La quiralidad es una propiedad fundamental en química y biología.
- La inducción de la quiralidad en polímeros es crucial para aplicaciones avanzadas.
- Los marcos metálico-orgánicos (MOF) ofrecen nanoambientes sintonizables para la síntesis de materiales.
Objetivo del estudio:
- Para investigar la transferencia de quiralidad de un MOF quiral a un polímero achiral.
- Para explorar la influencia del nanoconfinamiento en la quiralidad del polímero.
- Desarrollar un método para crear y estabilizar polímeros quirales.
Principales métodos:
- Síntesis de politiofeno no sustituido (PTh) dentro de los nanocanales quirales de MOF.
- Espectroscopia de dicroísmo circular (CD) para analizar las propiedades quirópticas.
- Análisis térmico para evaluar la estabilidad de la quiralidad.
Principales resultados:
- Achiral PTh adquirió quiralidad durante el confinamiento en un MOF quiral.
- Las propiedades quirópticas eran ajustables mediante el control de la carga de PTh y el grosor del ensamblaje.
- La quiralidad persistió en PTh incluso después de la eliminación del soporte MOF.
- El PTh recuperado exhibió una alta estabilidad térmica de quiralidad hasta 250 °C.
Conclusiones:
- Los MOF quirales proporcionan una plataforma eficaz para inducir y controlar la quiralidad del polímero.
- El nanoconfinamiento es una estrategia viable para crear polímeros ópticamente activos.
- Este método facilita el estudio de la quiralidad entre y dentro de la cadena en conjuntos de polímeros.
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