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Regulación de topología basada en enlaces de hidrógeno intramoleculares de marcos orgánicos covalentes
Yongwu Peng1,2, Liuxiao Li1, Chongzhi Zhu2
1Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Journal of the American Chemical Society
|July 7, 2020
Resumen
Los investigadores controlan las topologías de red en marcos orgánicos covalentes 2D (COF) ajustando los sustituyentes de enlace molecular. Esto permite la síntesis selectiva de diversas estructuras de COF con propiedades ópticas ajustables.
Área de la Ciencia:
- Ciencias de los materiales
- Química supramolecular
- Nanotecnología
Sus antecedentes:
- La creación de redes moleculares con topologías específicas es crucial pero desafiante.
- Se requiere un control preciso de la síntesis química para diversas estructuras de red.
Objetivo del estudio:
- Desarrollar una estrategia para regular las topologías de red de los marcos orgánicos covalentes 2D (COF).
- Para lograr la síntesis topológicamente selectiva de COFs 2D utilizando enlaces moleculares idénticos.
Principales métodos:
- Utilizando la conmutación conformacional de los enlaces moleculares a través de la alteración del sustituyente.
- Utilizando microscopía electrónica de transmisión de baja dosis y alta resolución para la determinación de la estructura cristalina.
Principales resultados:
- Sintetizó con éxito dos COFs 2D distintos y altamente cristalinos mediante la modificación de los sustituyentes de enlace.
- Identificó el enlace de hidrógeno intramolecular como la fuerza impulsora para la conmutación conformacional del enlace.
- Capacidad demostrada de modificación posintética, incluida la complejación de boro.
Conclusiones:
- La estrategia propuesta controla efectivamente las topologías de COF a través de la conformación del enlace molecular.
- Este enfoque diversifica significativamente las estructuras de COF y permite una funcionalidad avanzada.
- Los COF resultantes exhiben propiedades ópticas únicas como el encendido por fluorescencia y la emisión inducida por agregación.
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