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Hidrofluoración fotocatalítica dirigida por enlace de hidrógeno: superando el control electrónico
Mohammad B Khaled1, Roukaya K El Mokadem1, Jimmie D Weaver1
1Department of Chemistry, Oklahoma State University , Stillwater, Oklahoma 74078, United States.
Journal of the American Chemical Society
|August 25, 2017
Resumen
Una nueva estrategia de enlace de hidrógeno controla la regioselectividad en la funcionalización C-F fotocatalítica de los arenes fluorados. Este método acelera la desfluoración y permite una síntesis eficiente de compuestos valiosos como Januvia
Área de la Ciencia:
- Química orgánica
- Fotocatálisis
- Química del fluor
Sus antecedentes:
- La funcionalización fotocatalítica C-F permite la síntesis de arenos multifluorados.
- La regioselectividad generalmente se rige por la electrónica de sustrato, lo que limita el alcance sintético.
- La fragmentación del fluoruro de los aniones radicales dicta la regioselectividad.
Objetivo del estudio:
- Investigar la influencia del enlace de hidrógeno en la regioselectividad de la funcionalización C-F.
- Explorar la aceleración de la velocidad en la hidrodesfluoración a través de enlaces de hidrógeno intramoleculares.
- Demostrar la utilidad sintética en la preparación de compuestos fluorados comercialmente relevantes.
Principales métodos:
- Las reacciones de funcionalización C-F fotocatalíticas.
- Investigación de los intermediarios de aniones radicales.
- Estudios de regioselectividad dirigidos por enlaces de hidrógeno.
- Síntesis de un precursor de Januvia.
Principales resultados:
- Un enlace de hidrógeno colocado estratégicamente anula el control electrónico inherente de la regioselectividad.
- Aceleración significativa de la velocidad observada para la hidrodefluoración de los enlaces C-F involucrados en el enlace de hidrógeno.
- El enlace de hidrógeno facilita la fragmentación del enlace C-F y la extrusión de fluoruro.
- Se logró una síntesis acelerada de un intermediario clave para Januvia.
Conclusiones:
- El enlace de hidrógeno es una herramienta poderosa para controlar la regioselectividad en la funcionalización C-F.
- El método desarrollado ofrece una ruta más eficiente a las arenas multifluoradas importantes.
- Este enfoque proporciona una nueva estrategia para la síntesis de productos farmacéuticos intermedios.
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