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Fluoración nucleofílica divergente bajo catálisis de enlace de hidrógeno: un estudio computacional y experimental

Matthew A Horwitz¹, Alexander B Dürr¹, Konstantinos Afratis¹

¹Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.

Journal of the American Chemical Society

|April 20, 2023

Resumen

Los investigadores desarrollaron nuevos métodos catalíticos para las reacciones de fluoración nucleófila. Estos enfoques controlan los resultados regioquímicos, lo que permite la síntesis de isómeros específicos de fluoroamina a partir de un solo precursor utilizando catalizadores de urea.

Área de la Ciencia:

Química orgánica
Catálisis
Química de la fluoración

Sus antecedentes:

La regioselectividad controlada en la fluoración nucleofílica utilizando fluoruro de metales alcalinos sigue siendo un desafío significativo.
El desarrollo de sistemas catalíticos para el control preciso de las reacciones de fluoración es crucial para la química sintética.

Objetivo del estudio:

Presentar dos enfoques sinérgicos para los resultados regioquímicos controlados en las reacciones de fluoración nucleófila.
Explorar el uso de la catálisis de enlace de hidrógeno, específicamente los catalizadores de urea, para dirigir las vías de fluoración.

Principales métodos:

Utilizando catalizadores de urea donante con enlace de hidrógeno para modular la densidad de carga de fluoruro.
Investigación de la regioselectividad cinética en la fluoración de sales asimétricas de aziridinio.
Informe de un reordenamiento diotrópico formal catalizado por urea para la edición regioquímica.

Principales resultados:

Se ha demostrado que los catalizadores de urea influyen en la regioselectividad cinética en la fluoración de las sales de aziridinium.
Se logra la edición regioquímica a través de un reordenamiento diotrópico controlado termodinámicamente que incluye escisión de enlaces C-F y rebote de fluoruro.
Permitió el acceso a los regioisómeros de fluoroamina enriquecidos con enantio de un solo precursor de cloroamina.

Conclusiones:

Se han presentado nuevas estrategias sinérgicas para la fluoración nucleofílica regioselectiva.
Destacó la utilidad de la catálisis de enlace de hidrógeno a base de urea en el control de las vías de reacción.
Se han abierto nuevas vías para la organocatálisis asimétrica regiodivergente.

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