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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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Corrales conjugados quirales
Melissa Ball1, Brandon Fowler1, Panpan Li2,1
1†Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|July 31, 2015
Resumen
Los investigadores desarrollaron nuevos macrociclos conjugados con donantes de electrones alternos (bitiofeno) y aceptores (perileno diimida). Estas moléculas exhiben estereoisómeros únicos y un mecanismo de "salto intramolecular" para la interconversión.
Área de la Ciencia:
- Química orgánica
- Química supramolecular
- Ciencias de los materiales
Sus antecedentes:
- Los macrociclos conjugados son cruciales en la química supramolecular.
- El diseño de macrociclos con cavidades y propiedades electrónicas específicas sigue siendo un desafío.
Objetivo del estudio:
- Introducir un nuevo motivo de diseño para macrociclos conjugados tensados.
- Para crear macrociclos con unidades alternas de donantes y aceptadores de electrones.
- Investigar la estereoquímica y la dinámica de estos nuevos macrociclos.
Principales métodos:
- Síntesis de macrociclos con un patrón A-B-A-B utilizando el biotiofeno (donante) y el derivado de perileno diimida (aceptor).
- Cromatografía líquida quiral de alto rendimiento (HPLC) para la separación de estereoisómeros.
- Análisis espectroscópico y cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- Formación de macrociclos con una cavidad elíptica persistente revestida por átomos de azufre y las caras π del perilenodiimido.
- Existencia de formas quirales y aquirales, con tres estereoisómeros separados con éxito.
- Observación de un mecanismo de salto intramolecular para la interconversión de estereoisómeros.
- Amplio espectro de absorción visible y transferencia de electrones inducida por la luz del bitioeno a la perileno diimida.
Conclusiones:
- El nuevo motivo de diseño permite la construcción de macrociclos complejos, tensados y conjugados.
- El mecanismo de salto intramolecular identificado ofrece información sobre la dinámica del macrociclo.
- Estos macrociclos poseen interesantes propiedades fotofísicas debido a la transferencia intramolecular de electrones.
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