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Complejos radicales fotocrómicos que muestran disociación de enlaces heterolíticos
Ryosuke Usui1, Katsuya Yamamoto2, Hajime Okajima2
1Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan.
Journal of the American Chemical Society
|May 5, 2020
Resumen
Los investigadores desarrollaron nuevas moléculas fotocrómicas que pueden cambiar entre la disociación de enlaces de homólisis y heterólisis. Este avance ofrece materiales fotointerruptores versátiles con propiedades ajustables para aplicaciones avanzadas.
Área de la Ciencia:
- Ciencias de los materiales
- Química orgánica
- La fotoquímica
Sus antecedentes:
- Los materiales fotocrómicos exhiben diversas propiedades de conmutación por fotosíntesis a través de la homólisis y la heterólisis.
- Los marcos moleculares existentes carecen de control sobre el cambio entre la homólisis y la heterólisis con alta durabilidad.
- Los biradicales y zwitteriones generados poseen propiedades y aplicaciones distintas.
Objetivo del estudio:
- Diseñar y sintetizar nuevas moléculas fotocrómicas con disociación de enlaces controlable.
- Investigar la influencia de los sustituyentes en el cambio entre la homólisis y la heterólisis.
- Para expandir la versatilidad de los materiales de fotoswitch más allá de los marcos convencionales.
Principales métodos:
- Síntesis de nuevas moléculas fotocrómicas basadas en el marco del complejo de radicales fenoxilo-imidazolilo (PIC).
- Modificación de la fracción de fenoxilo con sustituyentes donantes de electrones fuertes.
- Investigación de los procesos de disociación de enlaces fotoinducidos (homólisis frente a heterólisis).
Principales resultados:
- El marco convencional de PIC muestra homólisis fotoinducida.
- La sustitución con grupos donantes de electrones cambió el proceso de disociación de la homólisis a la heterólisis.
- Demostró una estrategia para controlar la disociación de enlaces de estado excitado en sistemas fotocrómicos.
Conclusiones:
- Desarrolló una nueva estrategia para afinar la disociación de enlaces fotocrómicos.
- Permitió el desarrollo de fotointerruptores radicales y zwitteriónicos versátiles.
- Avanzó el diseño de materiales de conmutación fotográfica con funcionalidades controlables.
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