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Ensamblaje helicoidal macroscópico de polímeros de coordinación unidimensional: Inversión de la helicoidalidad
Jia-Ge Jia1,2, Chen-Chen Zhao3, Yi-Fan Wei1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, P. R. China.
Journal of the American Chemical Society
|October 27, 2023
Resumen
Este estudio demuestra el uso de disolventes para controlar la estructura helicoidal de los polímeros de coordinación quiral (PC). Los diferentes disolventes inducen varias morfologías, incluidas las superhélices con quiralidad sintonizable, que ofrecen nuevas posibilidades para el diseño de materiales quirales.
Área de la Ciencia:
- Química de coordinación
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- El ensamblaje de hélices macroscópicas con quiralidad controlable en sistemas artificiales es un desafío.
- Los polímeros de coordinación quiral (PC) ofrecen el potencial para crear estructuras helicoidales complejas.
- Comprender los mecanismos de formación de los autoensamblajes quirales es crucial para el diseño.
Objetivo del estudio:
- Utilizar disolventes como herramienta para inducir y controlar la formación de hélices macroscópicas en polímeros de coordinación quiral.
- Investigar la influencia de la composición del disolvente en la morfología y el sentido helicoidal de los PC autoensamblados.
- Para explorar el potencial de estos CPs helicoidales quirales en aplicaciones como el reconocimiento quiral.
Principales métodos:
- Síntesis de polímeros de coordinación quiral utilizando un sistema Ni/R-,S-BrpempH2.
- Variación sistemática de las mezclas de disolventes (agua con isómeros de acetonitrilo, metanol, etanol o propanol) para controlar el autoensamblaje.
- Caracterización de las morfologías resultantes mediante microscopía y análisis estructural.
- Cálculos teóricos para racionalizar las estructuras helicoidales observadas.
- Estudios de adsorción para evaluar las capacidades de reconocimiento quiral.
Principales resultados:
- Formación dependiente del disolvente de diversas morfologías: cintas retorcidas, cristales con forma de aguja, nanofibras y superhélices.
- Inducción exitosa de hélices macroscópicas en polímeros de coordinación quirales mediante ajuste de la composición del disolvente.
- Control sobre el sentido helicoidal (izquierdo o derecho) de las súper hélices mediante el uso de diferentes isómeros de propanol (NPA vs. IPA).
- Demostración del comportamiento de reconocimiento quiral en los CP helicoidales sintetizados.
Conclusiones:
- Los disolventes son herramientas efectivas para dirigir el autoensamblaje de polímeros de coordinación quirales en estructuras helicoidales macroscópicas.
- El sentido helicoidal de las estructuras autoensambladas puede controlarse con precisión mediante la elección del disolvente, en particular mediante el uso de isómeros.
- Este enfoque proporciona una vía para desarrollar nuevos materiales quirales con morfologías helicoidales ajustables y funcionalidades potenciales.
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