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Ditieniletenos activados por la luz visible inducidos por la transferencia intramolecular de protones

Hancheng Xi¹, Zhipeng Zhang¹, Weiwei Zhang¹

¹Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Shanghai Key Laboratory of Functional Materials Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering , East China University of Science & Technology , Shanghai 200237 , China.

Journal of the American Chemical Society

|October 29, 2019

Resumen

Los investigadores desarrollaron nuevos dietieniletenos (DTE) que cambian usando solo luz visible, evitando la radiación ultravioleta dañina. Este avance utiliza un proceso de transferencia de protones intramolecular (IPT) para aplicaciones fotocrómicas eficientes y reversibles.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
La fotoquímica

Sus antecedentes:

Los dietieniletenos (DTE) son conocidos por su fotocromatismo sensible a la luz, su estabilidad térmica y su resistencia a la fatiga.
Los sistemas DTE existentes a menudo requieren luz ultravioleta (UV) de alta energía para la fotociclización, lo que plantea problemas de seguridad.
El desarrollo de DTE activados por luz visible es crucial para aplicaciones más amplias y seguras.

Objetivo del estudio:

Para diseñar y sintetizar nuevos DTE capaces de todo el fotocromismo dirigido por luz visible.
Investigar el mecanismo que permite la activación de la luz visible en las DTE.
Establecer una plataforma general para la creación de materiales fotocrómicos seguros y sensibles a la luz visible.

Principales métodos:

Diseño racional de las DTE que incorporan un grupo funcional de transferencia intramolecular de protones (IPT).
Análisis espectroscópico para caracterizar las propiedades de absorción y el comportamiento fotocrómico.
Evaluación de la eficiencia de la conmutación fotográfica en disolventes polares y sistemas de gel polimérico.

Principales resultados:

DTEs diseñados con éxito con una banda de absorción desplazada al rojo adicional debido a IPT.
Se ha demostrado la eficiencia de la fotociclización de DTE utilizando luz visible (450 nm).
Logró un excelente rendimiento de conmutación fotográfica reversible tanto en estado de solución como en gel, evitando la luz UV.

Conclusiones:

El proceso IPT proporciona una estrategia viable para crear DTE totalmente impulsados por luz visible.
Estos nuevos DTE ofrecen una alternativa segura y eficiente a los sistemas activados por rayos UV.
La plataforma desarrollada permite una amplia aplicabilidad en varios sistemas fotocrómicos, particularmente en geles poliméricos.

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