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Nanografeno curvado negativamente con unidades heptagonales y [5] de heliceno

Zijie Qiu¹, Sobi Asako², Yunbin Hu¹

¹Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.

Journal of the American Chemical Society

|August 19, 2020

Resumen

El nanografeno curvado negativamente (NG) fue sintetizado inesperadamente. Este nuevo material exhibe propiedades mecanocrómicas y emisión en estado sólido, con aplicaciones potenciales en materiales avanzados.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
Nanotecnología

Sus antecedentes:

Los derivados del grafeno son cruciales en los materiales avanzados.
La exploración de nuevas estructuras de nanografeno con propiedades únicas está en curso.

Objetivo del estudio:

Sintetizar y caracterizar un nuevo nanografeno curvado negativamente (NG).
Investigar las propiedades estructurales, electrónicas y ópticas del NG sintetizado.

Principales métodos:

Síntesis por reordenamiento de arilo y deshidrogenaciones ciclónicas.
Confirmación estructural mediante el uso de cristalografía de rayos X.
Cálculos teóricos para apoyar los mecanismos de reacción.
Cromatografía líquida de alto rendimiento con quiral para resolución de enantiómeros.
Espectroscopia de dicroísmo circular para el análisis enantiomérico.

Principales resultados:

Síntesis inesperada de nanografeno curvado negativamente (NG 4) con dos heptagones y una fracción [5] de heliceno.
La cristalografía de rayos X confirmó estructuras en forma de silla de montar de los intermediarios y NG 4.
Los cálculos teóricos favorecieron la reorganización del arilo sobre la formación de heliceno.
NG 4 mostró un cambio de color mecanocrómico reversible y una emisión en estado sólido.
Los enantiómeros de NG 4 mostraron efectos de algodón moderados en espectros de dicroísmo circular.

Conclusiones:

Se sintetizó con éxito un nuevo nanografeno curvado negativamente.
El material posee propiedades mecanocrómicas y fotoluminiscentes únicas.
El estudio proporciona información sobre la síntesis y las propiedades de los nanógrafos curvos.

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