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Cadros orgánicos covalentes ligados al cianuro habilitados por la sustitución aromática dinámica nucleofílica

Zepeng Lei¹, Lacey J Wayment¹, Jackson R Cahn¹

¹Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.

Journal of the American Chemical Society

|September 27, 2022

Resumen

Las estructuras orgánicas covalentes altamente cristalinas ligadas al cianuro (CN-COF) se sintetizaron utilizando un método de sustitución aromática dinámica nucleofílica. Este enfoque produce materiales estables con una excelente selectividad de dióxido de carbono, lo que demuestra una amplia aplicabilidad.

Área de la Ciencia:

Ciencias de los materiales
Química orgánica
Química supramolecular

Sus antecedentes:

Las estructuras orgánicas covalentes (COF) son polímeros porosos cristalinos.
Lograr una alta cristalinidad en los FOC puede ser un desafío.
La química covalente dinámica ofrece vías para la autocorrección y la mejora de la cristalinidad.

Objetivo del estudio:

Informar sobre la primera síntesis de COFs altamente cristalinos ligados al cianuro.
Investigar el uso de la sustitución aromática dinámica nucleofílica (S_NAr) para la síntesis de COF.
Explorar las características estructurales y las propiedades de los CN-COF sintetizados.

Principales métodos:

Utilizando reacciones S_NAr reversibles catalizadas por el triazabiciclodeceno.
Utilizan 2,4,6-trifenoxi-1,3,5-triazina y difenoles como bloques de construcción.
Realización de estudios de expansión isoreticular para demostrar la versatilidad sintética.

Principales resultados:

Se obtienen COF altamente cristalinos ligados al cianuro a través de un mecanismo de autocorrección.
Se observó un único apilamiento de AA'- en la columna vertebral flexible debido a la unión de hidrógeno.
Se ha demostrado la aplicabilidad general del método sintético mediante la expansión isoreticular.
Los CN-COF sintetizados exhibieron una buena estabilidad y una alta selectividad CO₂/N_2.

Conclusiones:

La química dinámica de S_NAr es una estrategia viable para sintetizar COFs altamente cristalinos.
El método desarrollado proporciona acceso a CN-COF robustos con estructuras sintonizables.
Estos materiales son prometedores para las aplicaciones de captura de carbono debido a la adsorción selectiva de CO2.

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