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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
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Pretzelanes con Chiralidad Planar y Capacidades de Reconocimiento de Huéspedes
Songna Zhang1,2, Yuxi Wei1, Qiong Chen1
1Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
Journal of the American Chemical Society
|September 26, 2025
Resumen
Los investigadores sintetizaron grandes macrociclos llamados pretzelanos utilizando la catención, logrando altos rendimientos debido a los enlaces dinámicos de hidrazona y los efectos hidrofóbicos. Estos macrociclos quirales pueden encapsular huéspedes y protegerlos de la oxidación.
Área de la Ciencia:
- Química supramolecular
- Síntesis orgánica
- Química entre anfitrión y huésped
Sus antecedentes:
- El desarrollo de macrociclos con reconocimiento de huéspedes es crucial en la química huésped-huésped.
- La síntesis eficiente de macrociclos grandes y robustos sigue siendo un desafío.
Objetivo del estudio:
- Para sintetizar grandes macrociclos (pretzelanos) con un alto rendimiento.
- Explorar el reconocimiento de huéspedes y las propiedades fotofísicas de estos macrociclos.
Principales métodos:
- Utilizando la catenación como la reacción de ligadura clave para el cierre del anillo.
- El uso de enlaces dinámicos de hidrazona para la corrección de errores y efectos hidrofóbicos para impulsar la formación de macrociclos.
- Caracterización de los pretzelanos sintetizados y sus interacciones huésped-huésped.
Principales resultados:
- Se han obtenido rendimientos pseudo cuantitativos para macrociclos con más de 100 átomos no hidrógenos.
- Los pretzelanos sintetizados que exhiben una quiralidad plana intrínseca debido a una unidad puente.
- Demostró la capacidad de la cavidad de pretzelane para encapsular huéspedes hidrofóbicos.
- Se ha demostrado la transferencia de electrones inducida por la foto para la protección de los huéspedes dentro del macrociclo.
Conclusiones:
- La catenación proporciona una ruta eficiente a las arquitecturas macrocíclicas complejas como las pretzelanas.
- La estructura quiral pretzelana permite interacciones y propiedades funcionales específicas entre huésped y huésped.
- Los pretzelanos pueden actuar como jaulas protectoras para las moléculas huéspedes, evitando la degradación fotoquímica.
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