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Control de múltiples estímulos sobre el ensamblaje y la unión de huéspedes en huéspedes metalo-supramoléculares
Ru-Jin Li1, Jacopo Tessarolo1, Haeri Lee1
1Faculty of Chemistry & Chemical Biology, TU Dortmund University, Otto-Hahn-Straße 6, 44227 Dortmund, Germany.
Journal of the American Chemical Society
|March 6, 2021
Resumen
Los investigadores desarrollaron cuencos y jaulas metalo-supramoleculares conmutables utilizando un ligando fotocrómico. Estas estructuras se unen selectivamente a los huéspedes y se pueden reconfigurar utilizando luz, ligandos o aniones para materiales funcionales avanzados.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- Química de coordinación
Sus antecedentes:
- El ensamblaje de arquitecturas metalo-supramoleculares de múltiples componentes de manera no estadística es un desafío, lo que dificulta el desarrollo de materiales funcionales.
- Los ligandos fotocrómicos ofrecen un control dinámico sobre la estructura y las propiedades moleculares.
Objetivo del estudio:
- Diseñar y sintetizar cuencos y jaulas metalo-supramoleculares convertibles entre sí.
- Para investigar las capacidades de unión de huéspedes sensibles a los estímulos.
- Para explorar la síntesis de nuevas jaulas heterolépticas.
Principales métodos:
- Autoensamblaje de un ligando fotocrómico de DTE (L) con el catión Pd (II).
- Ingeniería de la esfera de coordinación usando donantes de quinolina voluminosos.
- Fotocambio reversible del ligando DTE entre las formas abierta (o-L) y cerrada (c-L).
- Caracterización de las estructuras de la jaula [Pd2 ((o-L) 4) ] (o-C) y del recipiente [Pd2 ((c-L) 3) (c-B).
Principales resultados:
- Se obtienen con éxito estructuras de interconversión de jaula (o-C) y cuenco (c-B).
- Se ha demostrado la encapsulación selectiva del huésped: la jaula encierra únicamente al huésped más pequeño (G1), mientras que el recipiente encierra a los tres huéspedes bisulfonados (G1-G3).
- Cajas heterolépticas nuevas sintetizadas [Pd2L^A_3L^B] utilizando el cuenco como plataforma.
- Comportamiento sensible a los estímulos: luz, ligandos y aniones (Br / Ag +) modulan la estructura, la unión al huésped y la complejación del ligando.
Conclusiones:
- El sistema desarrollado proporciona una ruta a complejas arquitecturas metalo-supramoleculares con preferencias ajustables de los huéspedes.
- Los efectos de cooperación entre unos pocos componentes permiten una alta complejidad estructural.
- Los cuencos y jaulas de interconversión representan una plataforma versátil para el desarrollo de materiales funcionales sensibles.
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