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(Hetero) arilazo-1,2,3-triazoles: fotointerruptores "clicados" para la funcionalidad versátil y el desacoplamiento

Dong Fang¹, Zhao-Yang Zhang¹, Zhichun Shangguan¹

¹School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Key Laboratory of Thin Film and Microfabrication (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200240, China.

Journal of the American Chemical Society

|September 3, 2021

Resumen

Los investigadores desarrollaron nuevos azoswitches de "desacoplamiento automático" mediante la integración de 1,2,3-triazoles en el núcleo del azoswitch. Estos fotointerruptores de azotriazol ofrecen propiedades sintonizables y una síntesis fácil a través de la química de clic para sistemas fotorresponsivos avanzados.

Área de la Ciencia:

Química molecular
Ciencias de los materiales
La fotoquímica

Sus antecedentes:

Los fotointerruptores moleculares como los azobenzenos son cruciales para los sistemas sensibles a la luz.
El acoplamiento electrónico intramolecular puede obstaculizar el rendimiento del interruptor fotográfico.
Las estrategias de desacoplamiento a menudo implican la inserción de unidades de enlace para interrumpir la comunicación electrónica.

Objetivo del estudio:

Introducir una nueva clase de azoswitches de "desacoplamiento automático" mediante la fusión de 1,2,3-triazoles en el núcleo del azoswitch.
Para demostrar la síntesis modular y las propiedades sintonizables de estos nuevos interruptores de azotriazol.
Explorar su potencial en el desarrollo de sistemas fotorresponsivos avanzados.

Principales métodos:

Síntesis de (hetero) arilazo-1,2,3-triazoles mediante el uso de la química de clic.
Caracterización de las propiedades del fotointerruptor, incluidos los rendimientos de fotoisomerización y las semividas térmicas.
Análisis computacional y experimental de la estructura electrónica y los efectos de los sustituyentes.

Principales resultados:

Desarrollo de arilazo-1,2,3-triazoles fácilmente sintetizados y funcionalizados de forma modular.
Se han obtenido rendimientos de fotoisomerización EZ (casi) cuantitativos.
Se ha demostrado que los isómeros Z con vida media térmica ajustable varían de días a años.
Se confirmó que la naturaleza conjugada cruzada de la unidad de triazol conserva la estructura electrónica del núcleo del interruptor fotográfico.

Conclusiones:

Los nuevos fotointerruptores de azotriazol exhiben propiedades inherentes de auto-desacoplamiento debido al 1,2,3-triazol integrado.
Su síntesis fácil, su fotofísica ajustable y su robusta estructura electrónica los convierten en herramientas moleculares versátiles.
Estos fotointerruptores son prometedores para el diseño de materiales y sistemas fotorresponsivos de alto rendimiento.

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