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Torcer bloques de construcción de plano a tetraédrico para la síntesis de estructuras orgánicas covalentes
Chao Gao1, Jian Li2,3, Sheng Yin1
1Sauvage Center for Molecular Sciences and Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , China.
Journal of the American Chemical Society
|February 14, 2020
Resumen
Los investigadores diseñaron dos nuevos marcos orgánicos covalentes (COF) con estructuras distintas mediante la modificación de los precursores de bifenilo. Este trabajo ofrece un nuevo nodo tetraédrico para crear diversos COF 3D.
Área de la Ciencia:
- Ciencias de los materiales
- Química supramolecular
- La cristalografía
Sus antecedentes:
- El diseño racional de marcos orgánicos covalentes (COF) con estructuras a medida es crucial para los materiales avanzados.
- Las estrategias sintéticas existentes a menudo se enfrentan a desafíos para lograr arquitecturas de COF diversas y predecibles.
Objetivo del estudio:
- Informar sobre la síntesis diseñada de dos nuevos COF, 2D-BPTA-COF y 3D-BMTA-COF, a partir de precursores a base de bifenilo.
- Investigar la influencia de los ortosustitutos en las estructuras y propiedades resultantes de los FOC.
- Introducir un nuevo nodo tetraédrico para la construcción de FOC tridimensionales (3D).
Principales métodos:
- Síntesis de precursores basados en bifenilo con varios orto-sustitutos.
- Cristalización y caracterización estructural de las COF resultantes mediante difracción de rayos X.
- Análisis de los ángulos diédricos y las estructuras topológicas de los COF sintetizados.
Principales resultados:
- Se sintetizaron con éxito dos COF, 2D-BPTA-COF y 3D-BMTA-COF, con alta cristalinidad y grandes áreas de superficie.
- 2D-BPTA-COF formó hojas 2D con apilamiento AB, mientras que 3D-BMTA-COF adoptó una estructura 7 veces interpenetrada con topología pts.
- La divergencia estructural se atribuyó al obstáculo estérico de los grupos metilo, alterando el ángulo diédrico bifenilo de ~ 0 ° a ~ 60 °.
Conclusiones:
- La introducción del obstáculo estérico en los bloques de construcción proporciona una estrategia general para controlar la dimensionalidad y la topología de COF.
- Este enfoque permite el diseño racional de COF con estructuras diversas mediante la torsión de bloques de construcción.
- Un nuevo nodo tetraédrico está disponible para la construcción de COFs complejos en 3D, expandiendo el alcance de la química de COF.
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