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Controlar el grado de interpenetración en marcos orgánicos covalentes tridimensionales quirales a través del ajuste

Kaixuan Wang^1,2, Bang Hou¹, Jinqiao Dong¹

¹School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.

Journal of the American Chemical Society

|July 24, 2024

Resumen

Los investigadores desarrollaron una estrategia de sintonía estérica para controlar la interpenetración en marcos orgánicos covalentes (COF). Este método modula el tamaño de los poros, la estabilidad y la funcionalidad para diversas aplicaciones en adsorción y catálisis.

Área de la Ciencia:

Ciencias de los materiales
Química supramolecular
Química orgánica

Sus antecedentes:

La interpenetración de la red es clave para la funcionalidad de los materiales porosos.
El control de la interpenetración en los marcos orgánicos covalentes (COF) para ajustar las propiedades es un desafío.

Objetivo del estudio:

Para demostrar una estrategia de ajuste estérico para el control de la interpenetración de COF.
Modular las propiedades fisicoquímicas y las funcionalidades de los COF.

Principales métodos:

COF quirales sintetizados mediante la condensación imina de tetraaldehídos con diferentes sustituyentes de alquilo y tetra (p-aminofenil) metano.
Topología de COF caracterizada, grado de interpenetración y propiedades basadas en el impedimento estérico del grupo alquilo.

Principales resultados:

Los sustituyentes alquilo en las paredes de los poros controlaban la interpenetración de COF minimizando las interacciones repulsivas.
Los diferentes grupos alquilo condujeron a topologías distintas (dia-c5 interpenetrado, dia-c4 no interpenetrado, dia-c1).
El grado de interpenetración influyó en la porosidad, la estabilidad y la adsorción/separación selectiva del tinte y la catálisis asimétrica.

Conclusiones:

El obstáculo estérico es una estrategia efectiva para ajustar la interpenetración, la porosidad y la estabilidad de COF.
Este enfoque amplía el ámbito de aplicación de los materiales de fibra de carbono.

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