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Proceso de sustitución radical para la activación mediada por radicales de boro ligados de cloruros de alquilo no

Chang-Zhen Fang¹, Bei-Bei Zhang¹, Yong-Liang Tu¹

¹School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing National Laboratory for Molecular Sciences, Beijing 100049, China.

Journal of the American Chemical Society

|September 12, 2024

Resumen

Los radicales borilo ligados (LBR) ahora activan los cloruros de alquilo no activados a través de un nuevo mecanismo de reemplazo de radicales, formando intermedios de alquilo borano. Este avance expande las aplicaciones de LBR en química radical más allá de la transferencia de átomos de halógeno (XAT).

Área de la Ciencia:

Química orgánica
La Química Radical
Metodología sintética

Sus antecedentes:

Los radicales borilo ligados (LBR) son efectivos para activar haluros de alquilo a través de la transferencia de átomos de halógeno (XAT).
La activación de cloruros de alquilo no activados utilizando LBR sigue siendo un desafío significativo en la química radical.

Objetivo del estudio:

Desarrollar un nuevo modo de activación para los LBR para superar el desafío de los cloruros de alquilo no activados.
Establecer una estrategia de formación de enlaces C(sp3) -C(sp3) utilizando este nuevo modo de activación.

Principales métodos:

Investigó un nuevo proceso de reemplazo radical entre LBR y cloruros de alquilo no activados.
Se utilizaron estudios mecanicistas para dilucidar la vía de reacción.
Se utiliza fosfato de potasio (K3PO4) como aditivo para facilitar la oxidación de un electrón.

Principales resultados:

Se demostró un nuevo modo de activación de LBR que implica el reemplazo radical con cloruros de alquilo no activados.
Se han identificado los intermediarios de borano alquilo como precursores de los radicales alquilo.
Generó con éxito radicales alquilo a partir de cloruros de alquilo no activados, lo que permite la formación de enlaces C ((sp3) -C ((sp3).

Conclusiones:

El mecanismo de reemplazo radical proporciona una nueva vía para la activación de cloruros de alquilo no activados con LBR.
Esta estrategia amplía significativamente el alcance de las aplicaciones de LBR en transformaciones radicales.
Los hallazgos enriquecen el campo de la química LBR, extendiendo su utilidad más allá de las reacciones XAT.

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