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Modificación del ensamblaje covalente desencadena transformaciones estructurales de los anillos borromeos
Wen-Xi Gao1, Hui-Jun Feng1, Yue-Jian Lin1
1Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers, Department of Chemistry , Fudan University , Shanghai 200433 , P. R. China.
Journal of the American Chemical Society
|May 24, 2019
Resumen
Los investigadores demuestran nuevas cascadas de transformación supramolecular utilizando el intercambio de ligandos y las reacciones de Diels-Alder. Estas reacciones permiten el enlace controlado, la desvinculación y la modificación de los anillos borromeos (BR) a través de cambios topológicos desencadenados.
Área de la Ciencia:
- Química supramolecular
- Química orgánica
- Ciencias de los materiales
Sus antecedentes:
- Los anillos borromeos (BR) son estructuras complejas entrelazadas con propiedades topológicas únicas.
- El control del montaje y desmontaje de las arquitecturas supramoleculares es crucial para el desarrollo de materiales avanzados.
Objetivo del estudio:
- Desarrollar una nueva familia de anillos borromeos (BR) sin plantilla y con bordes de tetrazina.
- Investigar los mecanismos de vinculación y desconexión dependientes de la concentración de estos BR.
- Explorar las transformaciones estructurales supramoleculares utilizando las reacciones de Diels-Alder de demanda de electrones inversa (IEDDA) para la modificación posterior al ensamblaje.
Principales métodos:
- Reacciones de intercambio de ligandos para la construcción de BR.
- Observación de la vinculación y desvinculación dependientes de la concentración de los BR.
- Reacciones inversas de demanda de electrones de Diels-Alder (IEDDA) para las transformaciones desencadenadas.
Principales resultados:
- Se han sintetizado con éxito BRs sin plantilla y con bordes de tetrazina.
- Se ha demostrado un control dependiente de la concentración sobre el enlace y la desconexión de BR.
- Modificación posterior al ensamblaje de los precursores borromeos a través de reacciones IEDDA.
- Transformaciones topológicas controladas observadas, incluida la desvinculación, inducidas por cambios estéricos de las reacciones IEDDA.
Conclusiones:
- Las cascadas de transformación supramoleculares ofrecen una plataforma versátil para construir y manipular arquitecturas complejas.
- Las reacciones IEDDA proporcionan una herramienta poderosa para desencadenar cambios topológicos y modificaciones posteriores al ensamblaje en los sistemas de anillos de Borromeo.
- El sistema desarrollado permite un control preciso de la topología supramolecular a través de estímulos externos.
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