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Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
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Enfoque dirigido a vértices hexatópicos para estructuras orgánicas covalentes vinileno-enlazadas con topologías
Zixing Zhang1, Shuai Bi1, Fancheng Meng1
1School of Chemistry and Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China.
Journal of the American Chemical Society
|July 24, 2023
Resumen
Los investigadores desarrollaron nuevos polímeros porosos llamados COF. Estos materiales catalizan eficientemente las reacciones de brominación aromática utilizando luz verde, con resultados que dependen del tamaño de los poros.
Área de la Ciencia:
- Ciencias de los materiales
- Química orgánica
- Catálisis
Sus antecedentes:
- Desarrollo de nuevos materiales porosos para aplicaciones avanzadas.
- Exploración de las estructuras orgánicas covalentes (COF) con fines catalíticos.
- Necesidad de métodos catalíticos eficientes y selectivos en la síntesis orgánica.
Objetivo del estudio:
- Para sintetizar nuevos monómeros hexatópicos y construir COF ligados al vinileno.
- Investigar las propiedades estructurales y topológicas de los FOC resultantes.
- Evaluar el rendimiento catalítico de estos COF en las reacciones de brominación aromática.
Principales métodos:
- Síntesis de un monómero hexatópico D3-simétrico que incorpora 2,6-dimetilpiridina.
- Condensación del monómero con dialdehídos aromáticos ditópicos lineales para formar COF.
- Caracterización mediante difracción de rayos X en polvo (PXRD), sorción de nitrógeno, análisis de la distribución del tamaño de los poros y microscopía electrónica de transmisión (TEM).
Principales resultados:
- Preparación exitosa de dos COF ligados al vinileno con topologías heteroporosas.
- Demostración de la deslocalización π bien modelada dentro de las estructuras de COF debido a los enlaces de piridina y fenileno.
- Catalización eficiente de la brominación aromática bajo irradiación de luz verde, mostrando conversión dependiente del tamaño de los poros y regioselectividad.
Conclusiones:
- Los COF sintetizados poseen características estructurales únicas que permiten una catálisis eficiente.
- El tamaño de los poros de los COF juega un papel crucial en el control de la actividad catalítica y la selectividad.
- Estos materiales ofrecen una plataforma prometedora para las transformaciones catalíticas impulsadas por la luz en la síntesis orgánica.
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