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Transferencia dirigida de átomos de halógeno (DIXAT): una herramienta poderosa para la generación quimioselectiva de

Sidhant Wagulde¹, Kevin P Quirion², Turki M Alturaifi²

¹Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080-3021, United States.

Journal of the American Chemical Society

|August 1, 2025

Resumen

Un nuevo método de transferencia dirigida de átomos de halógeno (DIXAT) permite la activación selectiva de bromuros de arilo sobre yoduros de arilo, superando las tendencias tradicionales de reactividad. Este avance permite un control preciso en la generación de radicales de arilo para la síntesis química avanzada.

Área de la Ciencia:

Química orgánica
Catálisis
La Química Radical

Sus antecedentes:

La transferencia de átomos de halógeno (XAT) y la transferencia de electrones individuales (SET) son métodos comunes para la generación de radicales de arilo.
La reactividad en XAT y SET se rige típicamente por las energías de disociación de enlaces y los potenciales de reducción, favoreciendo a los yoduros de arilo sobre los bromuros de arilo.
Los métodos existentes no superan estas tendencias de reactividad inherentes.

Objetivo del estudio:

Desarrollar una nueva estrategia que invierta las tendencias de reactividad típicas en la generación de radicales arilos.
Para permitir la activación quimioselectiva de los bromuros de arilo, incluso en presencia de yoduros de arilo.
Para lograr un control preciso de la generación de radicales de arilo basado en la orientación espacial.

Principales métodos:

Desarrollo de una estrategia de transferencia dirigida de átomos de halógeno (DIXAT).
Utilizando DIXAT para las reacciones de arilación catalizadas por níquel.
Aplicación de DIXAT en la carboarilación en cascada de enlaces C ((sp3) -H remotos en aminas alifáticas.
El uso de auxiliares atados para la funcionalización de C-H selectiva del sitio a través de procesos 1,6- o 1,7-HAT.

Principales resultados:

DIXAT activa con éxito los bromuros de arilo selectivamente sobre los yoduros de arilo, independientemente de los BDE y los potenciales de reducción.
El método permite un control preciso de la generación de radicales de arilo a través de la activación dirigida.
Aplicación exitosa en la funcionalización C-H catalizada por níquel de aminas alifáticas, incluidas las modificaciones en etapa tardía.
Simplicidad operativa demostrada, alta tolerancia del grupo funcional y amplio alcance del sustrato.

Conclusiones:

La estrategia DIXAT representa un avance significativo en el control de la generación de radicales arilos.
Este método supera las limitaciones de reactividad inherentes a los procesos XAT y SET tradicionales.
La técnica desarrollada proporciona una herramienta poderosa para la funcionalización selectiva de C-H, particularmente en moléculas complejas.

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