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Fotocromismo negativo rápido del complejo de radicales fenoxilo-imidazolilo con puente de 1,1'-binaftil
Tetsuo Yamaguchi1, Yoichi Kobayashi1, Jiro Abe1
1Department of Chemistry, School of Science and Engineering, Aoyama Gakuin University , 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan.
Journal of the American Chemical Society
|December 30, 2015
Resumen
Los investigadores desarrollaron un nuevo compuesto fotocrómico negativo, BN-PIC, para el fotoswitching rápido. Este material exhibe rápidos cambios de color con la luz visible y una rápida reacción térmica, ideal para aplicaciones fotorresponsivas avanzadas.
Área de la Ciencia:
- Ciencias de los materiales
- La fotoquímica
- Química orgánica
Sus antecedentes:
- El fotocromismo negativo permite el cambio de color a través de la luz visible, beneficioso para aplicaciones internas de materiales.
- Los compuestos fotocrómicos negativos existentes muestran tiempos de reacción térmica lentos (minutos).
- Existe una necesidad de materiales fotocrómicos negativos de respuesta rápida para aplicaciones avanzadas.
Objetivo del estudio:
- Para desarrollar un nuevo compuesto fotocrómico negativo con capacidades de conmutación rápida.
- Investigar las propiedades fotocrómicas y la cinética de reacción térmica del nuevo compuesto.
- Para explorar el impacto de la quiralidad en la reacción fotocrómica.
Principales métodos:
- Síntesis de un complejo de radicales fenoxilo-imidazolilo con puente de 1,1'-binaftil (BN-PIC).
- Experimentos de conmutación fotocrómica mediante irradiación de luz visible.
- Estudios cinéticos de la reacción térmica a temperatura ambiente.
- Mediciones de las propiedades quirópticas y análisis de los efectos de quiralidad del disolvente.
Principales resultados:
- BN-PIC demuestra una decoloración instantánea tras la exposición a la luz visible.
- La forma incolora fotogenerada de BN-PIC vuelve a la forma coloreada con una vida media de 1,9 segundos a temperatura ambiente.
- Se observaron cambios significativos en las propiedades quirópticas durante la reacción fotocrómica.
- La velocidad de reacción térmica está influenciada por la quiralidad del disolvente.
Conclusiones:
- Se ha desarrollado con éxito un nuevo compuesto fotocrómico negativo de respuesta rápida (BN-PIC).
- El BN-PIC permite un fotointercambio rápido con luz visible y exhibe una reacción térmica rápida.
- La capacidad del compuesto para alterar las propiedades quirópticas y la influencia de la quiralidad del disolvente abre nuevas vías para los materiales quirales fotorresponsivos.
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