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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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Marco orgánico covalente dinámico de un solo cristal para las alineaciones de huéspedes adaptativos
Shan Liu1, Lei Wei1, Tengwu Zeng1
1School of Physical Science and Technology, Shanghai Key Laboratory of High-Resolution Electron Microscopy, State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai 201210, China.
Journal of the American Chemical Society
|November 30, 2024
Resumen
Los marcos orgánicos covalentes dinámicos 3D (COF) exhiben la inclusión adaptativa del huésped a través del movimiento molecular. Este estudio revela la dinámica a nivel atómico y vías específicas que permiten la flexibilidad del marco para las esponjas moleculares.
Área de la Ciencia:
- Ciencias de los materiales
- La cristalografía
- Química supramolecular
Sus antecedentes:
- Los marcos orgánicos covalentes dinámicos 3D (COF) muestran cambios estructurales con las moléculas invitadas.
- Los mecanismos precisos de la flexibilidad de COF y la adaptación de los huéspedes no se comprenden completamente.
Objetivo del estudio:
- Proporcionar información a nivel atómico sobre la dinámica de COF-300 durante la inclusión de invitados.
- Elucidar la movilidad conformacional y la adaptabilidad huésped-huésped en los COF dinámicos.
Principales métodos:
- Crecimiento de un solo cristal de COF-300 utilizando un protocolo de transiminación por gradiente de difusión.
- Difracción de rayos X de alta resolución para el análisis estructural.
- Análisis cuantitativo de energía de las transformaciones estructurales.
Principales resultados:
- Dinámica de rotación y traslación observada de los enlaces iminos y las unidades fenílicas en COF-300.
- Ángulos de torsión de conmutación identificados en motivos de dimina de tereftalaldehído.
- Fases intermedias metastables descubiertas durante la evolución estructural.
- Se ha demostrado la adaptación del marco a diversas moléculas huéspedes con diversas alineaciones.
Conclusiones:
- La movilidad conformacional en los COF es impulsada por dinámicas moleculares específicas, no por movimientos arbitrarios.
- Los COF dinámicos se pueden diseñar como esponjas moleculares para estudiar estructuras líquidas.
- Las vías observadas se asemejan al plegamiento de proteínas, lo que sugiere un comportamiento dinámico predecible.
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