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Rotaxanos basados en Viologen de Dibenzo-30-corona-10
Hanlie R Wessels1, Carla Slebodnick1, Harry W Gibson1
1Department of Chemistry , Virginia Tech , Blacksburg , Virginia 24060 , United States.
Journal of the American Chemical Society
|May 19, 2018
Resumen
Los investigadores sintetizaron nuevos [2]- y [3]-rotaxanos utilizando dibenzo-30-corona-10 y viógenos. Estos hallazgos representan la primera formación exitosa de rotaxanos a partir de estos componentes moleculares específicos.
Área de la Ciencia:
- Química supramolecular
- Síntesis orgánica
- Reconocimiento molecular
Sus antecedentes:
- Dibenzo-30-corona-10 es un macrociclo conocido por sus propiedades de unión.
- Los viologenes son compuestos orgánicos con deficiencia de electrones con aplicaciones potenciales en dispositivos moleculares.
- La formación de moléculas mecánicamente entrelazadas como los rotaxanos se basa en interacciones específicas entre huésped y huésped.
Objetivo del estudio:
- Sintetizar y caracterizar nuevos rotaxanos utilizando el motivo de unión dibenzo-30-corona-10/viologen.
- Determinar la viabilidad de la formación de rotaxanos a partir del dibenzo-30-corona-10 y de los viógenos.
- Para investigar el comportamiento de complejación de la fase de solución entre estos componentes.
Principales métodos:
- Síntesis orgánica de los [2]-rotaxanos (compuestos 4, 7, 12) y el [3]-rotaxano (compuestos 8).
- Caracterización mediante espectroscopia de resonancia magnética nuclear (1H y 13C) y espectrometría de masas de alta resolución (HRMS).
- Cristalografía de rayos X para determinar la estructura en estado sólido de un [2]-rotaxano representativo (compuesto 7).
Principales resultados:
- Síntesis exitosa de tres [2]-rotaxanos y un [3]-rotaxano que incorporan el sistema dibenzo-30-crown-10/viologen.
- Datos espectroscópicos y espectrométricos de masas completos que confirman las estructuras de los rotaxanos sintetizados.
- Estructura cristalina de rayos X obtenida que proporciona información molecular detallada sobre la arquitectura del [2]-rotaxano.
- Se ha demostrado que el dibenzo-30-crown-10 forma complejos de pseudorotaxano con los viógenos en solución.
Conclusiones:
- El dibenzo-30-corona-10 y los viógenos pueden formar moléculas mecánicamente entrelazadas, específicamente rotaxanos.
- Este estudio presenta la primera síntesis reportada de rotaxanos utilizando esta combinación particular de macrociclo-invitado.
- Los resultados confirman la formación de complejos de pseudorotaxano en la fase de solución, validando la interacción de unión entre dibenzo-30-crown-10 y los viógenos.
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