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Nanografeno no benzenoide axialmente quiral con propiedad de segunda generación armónica

Liyuan Qin^1,2, Jin Xie³, Botao Wu⁴

¹Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Journal of the American Chemical Society

|April 18, 2024

Resumen

Los investigadores desarrollaron un nuevo nanografeno no benzenoide axialmente quiral, un material optoelectrónico único. Este nuevo compuesto exhibe dicroísmo circular de larga longitud de onda y propiedades de segunda generación armónica, expandiendo el alcance de las aplicaciones quirales del nanógrafo.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
Nanotecnología

Sus antecedentes:

Los nanografenos quirales (NG) son materiales optoelectrónicos prometedores.
Mientras que las NGs quirales helicoidales están bien estudiadas, los ejemplos quirales axialmente, especialmente los no benzenoides, son raros.

Objetivo del estudio:

Para informar de la primera síntesis de un nanografeno no benzenoide axialmente quiral.
Para investigar sus propiedades ópticas quirópticas y no lineales.

Principales métodos:

Síntesis por homoacoplamiento de silano de arilo catalizado por el paladio.
Cromatografía líquida quiral de alto rendimiento (HPLC) para la separación de enantiómeros.
Mediciones de dicroísmo circular (CD) y de segunda generación armónica (SHG).

Principales resultados:

Síntesis exitosa de un nuevo nanografeno no benzenoide axialmente quiral (2) con alta estabilidad atropisomérica.
Se ha demostrado actividad de CD hasta 660 nm, lo que indica una fuerte respuesta quiróptica.
Racemic 2 forma una red cristalina quiral que exhibe SHG, y los enantiómeros muestran propiedades SHG-CD.

Conclusiones:

Este trabajo introduce una nueva clase de nanografenos no benzenoides axialmente quirales.
El compuesto sintetizado exhibe propiedades ópticas únicas, incluyendo CD de larga longitud de onda y SHG.
Estos hallazgos abren nuevas vías para el diseño de materiales optoelectrónicos quirales avanzados.

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