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Modificación de las propiedades de los interruptores de espiropirano utilizando jaulas de coordinación con diferentes
Jinhua Wang1, Liat Avram2, Yael Diskin-Posner2
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
Journal of the American Chemical Society
|November 15, 2022
Resumen
La simetría de la jaula influye dramáticamente en las propiedades de las moléculas encapsuladas. Las diferentes formas de jaula estabilizan selectivamente los isómeros de espiropirano, afectando su color y reactividad fotoquímica, lo que permite el almacenamiento de información sintonizable.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- La fotoquímica
Sus antecedentes:
- El confinamiento molecular altera las propiedades físico-químicas.
- Los estudios anteriores se centraron en el tamaño y la polaridad de la cavidad, no en la simetría de la jaula.
- El efecto de la simetría de la jaula en las propiedades de los huéspedes sigue siendo poco explorado.
Objetivo del estudio:
- Investigar el impacto de la simetría de la jaula en las propiedades de los huéspedes encapsulados.
- Determinar cómo la forma de la jaula influye en el equilibrio y la reactividad de los isómeros.
- Explorar aplicaciones en el almacenamiento de información.
Principales métodos:
- Encapsulación de huéspedes de espiropirano en dos jaulas de coordinación basadas en Pd con diferentes simetrías (T y D2).
- Análisis espectroscópico para monitorear las poblaciones de isómeros y el comportamiento fotoquímico.
- Investigación de las relaciones estructura-propiedad basadas en la simetría de la jaula.
Principales resultados:
- La simetría de la jaula dicta la estabilización de isómeros específicos de espiropirano.
- Una jaula T-simétrica estabilizó el isómero incoloro e inerte.
- Una jaula simétrica D2 favorecía el isómero coloreado y fotointercambiable.
- La cinética de conmutación depende de los patrones de sustitución del espiropirano.
Conclusiones:
- La simetría de la jaula es un factor crítico en el control de las propiedades moleculares.
- La adaptación de la simetría de la jaula permite un control preciso sobre las poblaciones de isómeros huéspedes y la reactividad.
- Este control permite el desarrollo de medios de almacenamiento de información sintonizables y sensibles al tiempo.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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