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La generalidad del isomerismo arquitectónico en los marcos de inclusión del diseñador
K T Holman1, S M Martin, D P Parker
1Department of Chemical Engineering and Materials Science, University of Minnesota, Amundson Hall, 421 Washington Avenue, SE, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|July 18, 2001
Resumen
Los investigadores descubrieron nuevos isómeros estructurales en los sistemas de huéspedes organodisulfonados, ampliando las posibilidades de inclusión de los huéspedes. Estos materiales versátiles ofrecen cavidades sintonizables para diversas aplicaciones de reconocimiento molecular.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- Ingeniería de Cristal Ingeniería de Cristal.
Sus antecedentes:
- Los sistemas de huéspedes lamelares basados en grupos de guanidinium (G) y sulfonato (S) son conocidos por sus propiedades de inclusión.
- Trabajos anteriores identificaron bicapas discretas e isómeros simples de ladrillo, lo que limita el alcance de las combinaciones huésped-huésped.
Objetivo del estudio:
- Describir nuevos isómeros estructurales de los sistemas de huéspedes lamelares organodisulfonados.
- Para demostrar la generalización del isomerismo a varios pilares organodisulfonados.
- Explorar el papel de plantilla de las moléculas invitadas en la dirección del ensamblaje del marco y la selectividad.
Principales métodos:
- Síntesis y caracterización de nuevas arquitecturas anfitrionas lamelares (ladrillo en zigzag, doble ladrillo, ladrillo en V, bicapa entrecruzada).
- Investigación de las interacciones huésped-huésped y la selectividad utilizando varias moléculas huésped.
- Desarrollo de un sistema de clasificación para arquitecturas de host basado en topologías de proyección de pilares.
Principales resultados:
- Descubrimiento de cuatro nuevos isómeros estructurales: ladrillo en zigzag, ladrillo doble, ladrillo en V y bicapa cruzada.
- Demostración de que el isomerismo discreto de ladrillo simple en dos capas puede generalizarse a través de diferentes pilares de organodisulfonato.
- Evidencia de plantillas sistemáticas por parte de moléculas invitadas que influyen en la selectividad de los isómeros del marco durante el ensamblaje de la red.
Conclusiones:
- El sistema huésped organodisulfonato exhibe una notable versatilidad estructural más allá de las expectativas iniciales.
- Cada isómero del marco posee cavidades de inclusión únicas, lo que permite un alojamiento personalizado para los huéspedes.
- La naturaleza sintonizable y las vastas posibilidades arquitectónicas sugieren una amplia aplicabilidad para la inclusión de los huéspedes.
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