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Cuadros orgánicos covalentes enlazados por anillos fundidos
Jie Feng1, Ya-Jie Zhang1, Sheng-Hua Ma1
1State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou Magnetic Resonance Center, Lanzhou University, Lanzhou, Gansu 730000, China.
Journal of the American Chemical Society
|April 5, 2022
Resumen
Los investigadores desarrollaron nuevos marcos orgánicos covalentes vinculados a anillos fusionados (COF) utilizando un protocolo en cascada. Este avance en la química de enlace permite estructuras de COF altamente cristalinas y estables con un control mejorado.
Área de la Ciencia:
- Ciencias de los materiales
- Química orgánica
- Nanotecnología
Sus antecedentes:
- Los marcos orgánicos covalentes (COF) son cruciales para las estructuras robustas con funcionalidad ajustable.
- El desarrollo de una química de enlace avanzada es clave para mejorar las propiedades de los COF, como la cristalinidad y la estabilidad.
Objetivo del estudio:
- Lograr un nuevo nivel de complejidad y controlabilidad en la química de enlaces de COF.
- Para sintetizar el primer anillo fusionado ligado COFs con alta pureza, estabilidad y cristalinidad.
Principales métodos:
- Se empleó un protocolo en cascada que incluía la condensación por base de Schiff, la cicloadición intramolecular [4 + 2] y la deshidroaromatización.
- Los monómeros diseñados (salicilaldehídos O-propárgicos y anilinas multitópicas) se reaccionaron de una sola vez utilizando catalizadores de ácido de Brønsted o Lewis.
- La caracterización incluyó RMN en estado sólido, difracción de rayos X en polvo y HRTEM.
Principales resultados:
- Se han sintetizado con éxito COFs de pirano[4,3-b]piridina.
- Se ha logrado una formación altamente selectiva (> 94%) del enlace pirano[4,3-b]piridina, verificado por RMN cuantitativa y etiquetado con 13C.
- El enlace de anillo fundido dio como resultado una conformación completamente bloqueada, lo que contribuyó a una alta cristalinidad de COF.
Conclusiones:
- Este estudio representa un avance significativo en la química de enlaces de COF, pasando de enlaces/anillos individuales a anillos fusionados.
- El método desarrollado permite la construcción concisa de estructuras COF sofisticadas con una alta capacidad de control.
- Los COFs ligados por anillos fundidos exhiben una excelente pureza, estabilidad y cristalinidad, abriendo nuevas vías para el diseño de materiales.
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