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Construyendo estructuras orgánicas covalentes cristalinas a partir de bloques de construcción quirales
Hai-Sen Xu1, San-Yuan Ding1, Wan-Kai An1
1State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou, Gansu 730000, China.
Journal of the American Chemical Society
|September 2, 2016
Resumen
Los investigadores desarrollaron un método sencillo para crear marcos orgánicos covalentes funcionalizados quirales (COF). Estos nuevos materiales porosos, LZU-72 y LZU-76, demuestran robustez y alta actividad como organocatalizadores heterogéneos.
Área de la Ciencia:
- Ciencias de los materiales
- Química orgánica
- Catálisis
Sus antecedentes:
- Las estructuras orgánicas covalentes (COF) son materiales porosos cristalinos construidos a partir de unidades orgánicas.
- La síntesis de COF funcionales que son a la vez cristalinos y poseen las propiedades deseadas sigue siendo un desafío.
- Los COF quirales son particularmente interesantes para la catálisis asimétrica, pero su construcción es compleja.
Objetivo del estudio:
- Desarrollar una estrategia fácil para la construcción de COFs con funciones quirales.
- Sintetizar y caracterizar nuevas COF quirales utilizando un andamio rígido específico.
- Evaluar la actividad catalítica de los COF quirales sintetizados como organocatalizadores heterogéneos.
Principales métodos:
- Diseño y síntesis de un andamio rígido, 4,4'-(1H-benzo[d]imidazol-4,7-diyl) dianilina (2).
- Síntesis de un bloque de construcción quiral, (S)-4,4'-(2-(pirrolidina-2-il)-1H-benzo[d]imidazol-4,7-diil) diilina (3), que incorpora una porción quiral.
- Utilizando el bloque de construcción quiral para construir dos COF quirales, LZU-72 y LZU-76, a través del ensamblaje covalente.
Principales resultados:
- Síntesis exitosa del andamio rígido y el bloque de construcción con pirrolidina quiral.
- Construcción directa de dos nuevos COF quirales, LZU-72 y LZU-76, que demuestran cristalinidad y porosidad.
- Validación experimental de la robustez estructural y la alta actividad catalítica de los COF quirales sintetizados como organocatalisadores heterogéneos.
Conclusiones:
- Se ha establecido una estrategia fácil para la construcción directa de COFs funcionalizados quirales a partir de bloques de construcción quirales.
- Los COF quirales sintetizados (LZU-72 y LZU-76) son estructuralmente robustos.
- Estos nuevos COF quirales presentan un potencial significativo como organocatalizadores heterogéneos altamente activos para diversas transformaciones químicas.
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