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Perfluoroalquilación de metales fotorredóxicos de las organobromidas
Xiangbo Zhao1, David W C MacMillan1
1Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|November 9, 2020
Resumen
Los reactivos de Ruppert-Prakash permiten un ligero acoplamiento catalizado por el cobre para la fluoroalquilación de los organobromuros. Este método mediado por la luz introduce de manera eficiente los grupos trifluorometil, pentafluoroetil y heptafluoropropil, incluso en moléculas complejas.
Área de la Ciencia:
- Química organometálica
- Química orgánica sintética
- Química del fluor
Sus antecedentes:
- Los grupos fluoroalquilo son motivos cruciales en los productos farmacéuticos y la ciencia de los materiales.
- Los métodos tradicionales para introducir grupos fluoroalquilo pueden ser duros o limitados en su alcance.
- Los reactivos de tipo Ruppert-Prakash ofrecen fuentes accesibles y estables de nucleófilos fluoroalquilo.
Objetivo del estudio:
- Desarrollar un método suave y eficiente para el acoplamiento de fuentes de fluoroalquilo con organobromuros.
- Explorar el alcance y las limitaciones de una nueva reacción de perfluoroalquilación mediada por la luz.
- Demostrar la utilidad del método desarrollado para la funcionalización en etapa tardía de moléculas complejas.
Principales métodos:
- Reacción de acoplamiento cruzado catalizada por cobre utilizando reactivos del tipo Ruppert-Prakash (TMSCF3, TMSC2F5, TMSC3F7).
- Transformación mediada por la luz que procede a través de una vía de abstracción de átomos de halógeno mediada por radicales silílicos.
- Aplicación a una amplia gama de bromuros de arilo y alquilo con diferentes propiedades estéricas y electrónicas.
Principales resultados:
- Síntesis exitosa de varios aductos de trifluorometil, pentafluoroetil y heptafluoropropil.
- Condiciones de reacción leves demostradas y alta tolerancia funcional del grupo.
- Eficaz perfluoroalquilación en etapa tardía de análogos de fármacos, demostrando su aplicabilidad práctica.
Conclusiones:
- Se ha establecido un método novedoso, suave y versátil catalizado por cobre para la perfluoroalquilación.
- La vía silil-radical mediada por la luz proporciona una ruta eficiente a los compuestos fluoroalquilados complejos.
- Esta metodología ofrece un potencial significativo para el descubrimiento y desarrollo de fármacos a través de la funcionalización en etapa tardía.
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