Síntesis estereoselectiva de cuadrados moleculares y nudos de abuela
David A Leigh1, Lucian Pirvu1, Fredrik Schaufelberger1
1School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , U.K.
Journal of the American Chemical Society
|March 21, 2019
Resumen
Los investigadores sintetizaron estereoselectivamente nudos moleculares complejos, incluidos los nudos de la abuela y los cuadrados. Esto se logró utilizando nudos quirales como bloques de construcción, lo que demuestra un enfoque novedoso para la arquitectura molecular compleja.
Área de la Ciencia:
- Química supramolecular
- Síntesis orgánica
- Estereoquímica
Sus antecedentes:
- La síntesis de topologías moleculares complejas, como los nudos, presenta un desafío significativo en la química.
- Los sintones quirales son cruciales para la construcción de moléculas con una estereoquímica definida, análoga al enfoque quirónico.
Objetivo del estudio:
- Para reportar una síntesis estereoselectiva de la abuela molecular y los nudos cuadrados.
- Para utilizar los nudos superiores con complejo de lantánidos como "sintones de enredo" definidos estereocímicamente.
Principales métodos:
- Empleando nudos aéreos de tres cruces con manos específicas como sintetizadores de entrelazamiento.
- Utilizando la reacción de cicloadición de alquina-azida catalizada por cobre (CuAAC) para vincular los sintones.
- Utilizando la metátesis de olefinas de cierre de anillo (RCM) para formar la topología de los nudos de circuito cerrado.
- Caracterización a través de la espectroscopia RMN, la espectrometría de masas y el dicroísmo circular.
Principales resultados:
- Síntesis estereoselectiva exitosa de los nudos moleculares de la abuela y el cuadrado.
- Demostración de la combinación de sintones de la misma quiralidad para los nudos de abuela y de quiralidad opuesta para los nudos cuadrados.
- Eliminación eficiente de los iones lantánidos después del bloqueo topológico.
Conclusiones:
- La estrategia desarrollada permite la construcción de nudos complejos a partir de bloques de construcción quirales más simples.
- Este enfoque ofrece un nuevo método para la síntesis estereoselectiva de arquitecturas moleculares intrincadas.
- El método destaca la utilidad de los sintones de entrelazamiento en la química supramolecular.
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