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Difluorometilación de alquenos no activados utilizando freón-22 a través de la transferencia de átomos de halógeno

Zhi-Qi Zhang^1,2, Yue-Qian Sang³, Cheng-Qiang Wang²

¹Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, P. R. of China.

Journal of the American Chemical Society

|July 27, 2022

Resumen

Este estudio introduce un nuevo método para sintetizar compuestos fluorados utilizando clorodifluorometano (Freón-22). El proceso fotocatalítico agrega de manera eficiente grupos difluorometilo a los alquenos, ofreciendo un enfoque sostenible para la síntesis química valiosa.

Área de la Ciencia:

Química orgánica
Química del fluor
Fotocatálisis

Sus antecedentes:

La síntesis de compuestos fluorados es crucial en los productos farmacéuticos y la ciencia de los materiales.
El uso de fuentes abundantes y baratas de flúor sigue siendo un desafío importante.
Los métodos existentes a menudo carecen de eficiencia o requieren reactivos costosos.

Objetivo del estudio:

Desarrollar un nuevo método fotocatalítico para la hidrodifluorometilación.
Para utilizar el clorodifluorometano (Freón-22) como materia prima para el flúor.
Para lograr la difluorometilación selectiva de alquenos no activados.

Principales métodos:

Catálisis organofotorredóxica bajo irradiación de luz azul.
Transferencia de átomos de halógeno inducida por radicales de boro ligados a aminas terciarias (XAT).
Condiciones de reacción sin metales.

Principales resultados:

La metilación exitosa de una amplia gama de alquenos.
Se observó una alta eficiencia y selectividad para varios grupos funcionales y moléculas complejas.
Demostración de un protocolo sintético sin metales.

Conclusiones:

El método desarrollado proporciona una ruta eficiente a los compuestos difluorometilados a partir de alquenos y clorodifluorometano fácilmente disponibles.
El mecanismo de reacción implica un proceso favorable de transferencia de átomos de halógeno (XAT).
Este trabajo amplía la utilidad sintética de las materias primas de flúor baratas.

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