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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
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Las nanocintas de heliceno de un solo mango a través de la transferencia de información quiral
Xiao Xiao1, Qian Cheng2, Si Tong Bao2
1Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
Journal of the American Chemical Society
|October 28, 2022
Resumen
Los investigadores crearon las columnas vertebrales de heliceno ópticamente activas más largas hasta la fecha utilizando un bloque de construcción de heliceno. Este método permite la formación diastereoselectiva de [5] unidades de heliceno, lo que demuestra una transferencia de información estereoquímica eficiente en las nanocintas.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- Los helicenos son hidrocarburos aromáticos quirales con estructuras helicoidales únicas.
- Controlar la estereoquímica y extender la longitud de la columna vertebral del heliceno es un desafío.
- Los helicenos ópticamente activos tienen aplicaciones potenciales en el reconocimiento quiral y la electrónica molecular.
Objetivo del estudio:
- Desarrollar un método para sintetizar nanocintas de heliceno largas y ópticamente activas.
- Investigar la transferencia de información estereoquímica en las estructuras de heliceno.
- Explorar la formación de geometrías homoquirales en materiales basados en el heliceno.
Principales métodos:
- Utilizando un bloque de construcción de heliceno [6] como un "sargento" para inducir la formación fotoquímica diastereoselectiva de unidades de heliceno [5] como "soldados".
- La síntesis de las nanocintas de heliceno (P1 y P2) con diferentes proporciones de "sargento" a "soldado".
- Caracterización de las propiedades quirópticas de las nanocintas sintetizadas y de los oligómeros modelo (1-5).
Principales resultados:
- Con éxito sintetizó las columnas vertebrales de heliceno ópticamente activas más largas hasta la fecha, que comprenden 50-60 anillos de benceno orto-anulados.
- Se ha demostrado la transferencia de información estereocímica de los "sargentos" de heliceno [6] a los "soldados" de heliceno [5] en las nanocintas P1 y P2.
- Se confirmó la adopción preferente de geometrías homoquirales en oligómeros modelo discretos que utilizan el mismo diseño molecular.
Conclusiones:
- El método desarrollado proporciona acceso a las nanocintas de heliceno de una sola mano.
- El enfoque de "sargento-soldado" controla efectivamente la estereoquímica sobre las estructuras helicoidales extendidas.
- Este trabajo avanza en la síntesis de nanomateriales helicoidales complejos y ópticamente activos.
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