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Transformación dinámica entre marcos orgánicos covalentes y jaulas orgánicas discretas
Zhen Shan1, Xiaowei Wu1, Bingqing Xu1
1Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China.
Journal of the American Chemical Society
|December 9, 2020
Resumen
La química covalente dinámica permite la transformación estructural entre los marcos orgánicos covalentes (COF) y las jaulas. Los enlaces de borato e imina facilitan las conversiones reversibles de COF a jaula y de jaula a COF, dando lugar a materiales porosos estables.
Área de la Ciencia:
- Ciencias de los materiales
- Química orgánica
- Química supramolecular
Sus antecedentes:
- Las estructuras orgánicas covalentes (COF) son polímeros porosos cristalinos con diversas aplicaciones.
- Las jaulas moleculares discretas ofrecen propiedades únicas de anfitrión-invitado.
- Las transformaciones entre estas dos clases de materiales siguen siendo difíciles.
Objetivo del estudio:
- Desarrollar una nueva estrategia para la interconversión de las jaulas y las jaulas.
- Para utilizar la química covalente dinámica (DCC) para las transformaciones estructurales controladas.
- Explorar la estabilidad termodinámica de las estructuras resultantes.
Principales métodos:
- El uso de la química covalente dinámica (DCC) a través de reacciones de intercambio de enlaces.
- Utilizando enlaces de borato e imina como enlaces reversibles.
- Realización de experimentos de autoclasificación para determinar los productos termodinámicos.
Principales resultados:
- Se han demostrado con éxito por primera vez las transformaciones reversibles entre los COF y las jaulas.
- Se ha logrado la transformación de COF en jaula mediante enlaces de borato.
- Se ha logrado la transformación de la jaula a COF utilizando enlaces iminos.
- Se han identificado las jaulas de borato y las iminas COF como productos finales termodinámicamente estables.
Conclusiones:
- Estableció una estrategia de intercambio de enlaces inducida por el DCC para la interconversión de jaulas de COF.
- Ha cerrado la brecha entre las jaulas moleculares discretas y las COF poliméricas.
- Amplió la comprensión de la ciencia de los materiales porosos y la química covalente dinámica.
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