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Enantiopuro [Cs+/XeCryptophane]FeII4 L4 Superestructuras jerárquicas
Dawei Zhang1, Tanya K Ronson1, Jake L Greenfield1
1Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K.
Journal of the American Chemical Society
|April 30, 2019
Resumen
Los investigadores crearon una nueva estructura de jaula en jaula utilizando una cápsula de hierro autoensamblada para encapsular una jaula de criptofano covalente. Este sistema jerárquico demostró la unión controlada del huésped y la transferencia de información estereocímica, que afecta el reconocimiento molecular y la química supramolecular.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- Cristalografía Química
Sus antecedentes:
- Los anfitriones anidados jerárquicamente permiten un control preciso sobre las interacciones de los huéspedes dentro de las cavidades internas.
- Las cápsulas autoensambladas ofrecen plataformas sintonizables para arquitecturas moleculares complejas.
- La investigación de la comunicación entre capas en sistemas de múltiples componentes es crucial para los materiales funcionales avanzados.
Objetivo del estudio:
- Construir y caracterizar un nuevo complejo supramolecular de jaula en jaula.
- Para explorar las propiedades de unión de invitados y el comportamiento estereocímico del sistema jerárquico.
- Para demostrar la transferencia de información estereoquímica desde una jaula covalente interna a una cápsula externa autoensamblada.
Principales métodos:
- Autoensamblaje de una cápsula Fe (II) 4L4 a base de triazatruxeno.
- Encapsulación del criptofano-111 (CRY) dentro de la cápsula Fe ((II) 4L4).
- Cristalografía de rayos X para determinar la estructura del complejo de la muñeca rusa.
- Estudios vinculantes con cationes de cesio y átomos de xenón.
- Experimentos de unión enantioselectiva con CRY enantiopuro.
Principales resultados:
- Una cápsula Fe(II) 4L4 autoensamblada encapsuló con éxito la jaula covalente de criptofano-111 (CRY).
- El complejo de jaula en jaula resultante exhibió afinidades de unión alteradas para huéspedes como Cs + y Xe en comparación con CRY solo.
- La cristalografía de rayos X confirmó la encapsulación de Cs+ dentro del complejo [CRY]Fe(II) 4L4, revelando una carga inusual de 8+ en la cápsula externa.
- Se observó una alta enantioselectividad (530 veces) en la unión de CRY enantiopuro al tetraedro.
- Se produjo una transferencia de información estereoquímica, que condujo a complejos enantiopuros [invitado CRY] Fe (II) 4L4, con una estereoquímica que persiste incluso después del intercambio de invitados.
Conclusiones:
- La cápsula Fe ((II) 4L4) sirve como un huésped eficaz para la jaula CRY covalente, creando un sistema jerárquico funcional.
- La arquitectura de jaula en jaula permite la vinculación modulada del huésped y demuestra la transferencia de información estereoquímica.
- Este trabajo proporciona una nueva plataforma para diseñar sistemas supramoleculares sofisticados con aplicaciones en reconocimiento y detección molecular.
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