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Competencia entre la fluoración de enlaces C-C y C-H: un continuo de mecanismos de transferencia de electrones y

Muyuan Wang¹, Rozhin Rowshanpour², Liangyu Guan³

¹Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States.

Journal of the American Chemical Society

|October 4, 2023

Resumen

Este estudio revela un nuevo mecanismo para la fluoración radical de acetales cíclicos, que implica la oxidación por un radical centrado en N. Este descubrimiento permite nuevos métodos de fluoración química y electroquímica.

Área de la Ciencia:

Química orgánica
La fotoquímica
Mecanismos de reacción

Sus antecedentes:

Método fotoquímico previamente informado para la escisión de enlaces C-C/fluoración radical de acetales cíclicos utilizando Selectfluor y 9-fluorenona.
Necesidad de una comprensión mecanicista detallada de esta transformación.

Objetivo del estudio:

Para aclarar el mecanismo de la reacción de fluoración fotoquímica del acetal.
Desarrollar nuevas metodologías de fluoración química y electroquímica.
Investigar la competencia entre las vías de transferencia de electrones individuales (SET) y de transferencia de átomos de hidrógeno (HAT) en la fluoración acetal.

Principales métodos:

Estudio mecanicista detallado de la reacción fotoquímica.
Prueba de estudios conceptuales para nuevos métodos químicos y electroquímicos.
Cálculos de la teoría funcional de la densidad (DFT) para estudiar las vías de reacción.

Principales resultados:

Identificó un radical intermedio centrado en N derivado de Selectfluor como clave para la oxidación del sustrato, que difiere de la hipótesis inicial de transferencia de electrones fotoinducida.
Se han demostrado nuevas condiciones químicas y electroquímicas para la fluoración de enlaces C-C sin tensión.
Analizó la competencia entre las vías SET y HAT en la fluoración acetal y otras reacciones de fluoración C-H/C-C.

Conclusiones:

El mecanismo implica la oxidación del sustrato por un radical centrado en N, no la transferencia directa de electrones fotoinducida.
Ahora son factibles nuevas estrategias de fluoración química y electroquímica.
La comprensión de las vías SET vs. HAT es crucial para desarrollar reacciones selectivas de fluoración de C-H y C-C.

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