El enlace aniónico en el agua impulsa la adaptación estructural en un tetraedro FeII funcionalizado con azafosfatrato
Dawei Zhang1,2, Tanya K Ronson1, Jesús Mosquera1
1Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.
Journal of the American Chemical Society
|May 3, 2017
Resumen
Los investigadores crearon una jaula de FeII4L4 flexible y soluble en agua a partir de bloques de construcción de azafosfatrato. Esta jaula supramolecular adaptable se autoensambla en el agua para capturar varios aniones, lo que demuestra efectos de memoria de forma.
Área de la Ciencia:
- Química supramolecular
- Química de coordinación
- Ciencias de los materiales
Sus antecedentes:
- Los compuestos de azofosfatrato ofrecen propiedades estructurales y electrónicas únicas para el autoensamblaje.
- La síntesis con plantilla de aniones es una estrategia poderosa para construir arquitecturas supramoleculares complejas.
- Las jaulas hidrosolubles son deseables para aplicaciones en sistemas biológicos y ambientales.
Objetivo del estudio:
- Para sintetizar un nuevo tetraedro FeII4 L4 funcional utilizando subcomponentes de azofosfatrano.
- Investigar las capacidades de encapsulación aniónica y la adaptabilidad estructural de la jaula hidrosoluble resultante.
- Para explorar el comportamiento dinámico y los posibles efectos de memoria de forma de la jaula supramolecular.
Principales métodos:
- "Capacidad" igual o superior a 100 kW y con un rendimiento superior o igual a 200 W; o
- Los análisis espectroscópicos y cristalográficos para caracterizar el tetraedro FeII4 L4.
- Estudios de temperatura variable y experimentos de intercambio de invitados para sondear la dinámica y la flexibilidad de la jaula.
Principales resultados:
- Formación de un tetraedro FeII endohedralmente funcionalizado soluble en agua a través del autoensamblaje.
- Demostración de encapsulación de aniones dentro de la jaula, con volúmenes que van desde 35 hasta 219 Å3.
- Observación de la adaptación estructural dinámica a los aniones de la plantilla y un fenómeno de memoria de forma durante el desplazamiento del huésped.
Conclusiones:
- La jaula de FeII4 basada en azafosfatrato desarrollada es una plataforma versátil para el reconocimiento de aniones en medios acuosos.
- La jaula exhibe una flexibilidad significativa y un isomerismo estructural dinámico, adaptando su conformación basada en aniones encapsulados.
- El efecto de memoria de forma observado pone de relieve el potencial de materiales supramoleculares sensibles y reconfigurables.
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