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Síntesis de alquilfluoruros enriquecidos con enantio mediante la fluoración de complejos de boronato
Christopher Sandford1, Ramesh Rasappan1, Varinder K Aggarwal1
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|August 6, 2015
Resumen
Los ésteres borónicos secundarios quirales se convierten eficientemente en alquilfluoruros utilizando complejos de boronato y Selectfluor II. Este método logra una alta especificidad enantio, crucial para la síntesis de compuestos fluorados enantiopuros.
Área de la Ciencia:
- Química orgánica
- Química de la fluoración
- Síntesis estereoselectiva
Sus antecedentes:
- Los alquilfluoruros quirales son bloques de construcción importantes en los productos farmacéuticos y agroquímicos.
- El desarrollo de métodos eficientes y estereoselectivos para su síntesis sigue siendo un desafío.
Objetivo del estudio:
- Informar sobre un nuevo método para la conversión enantiospecífica de ésteres borónicos secundarios quirales en fluoruros de alquilo.
- Investigar el uso de complejos de boronato como nucleófilos en la fluoración electrofílica.
Principales métodos:
- Utilizó complejos de boronato, generados a partir de ésteres borónicos y PhLi, como nucleófilos.
- Se utiliza el Selectfluor II como agente fluorante electrófilo.
- Investigó el efecto del estireno como una trampa de radicales para mejorar la enantiospecificidad.
Principales resultados:
- Se ha logrado la conversión enantiospecífica de ésteres borónicos secundarios quirales en fluoruros de alquilo.
- Tiempos de reacción cortos demostrados para el proceso de fluoración.
- Se observó una enantiospecificidad casi completa en una amplia gama de sustratos.
Conclusiones:
- El método desarrollado proporciona una ruta eficiente a los alquilfluoruros enriquecidos enantioméricamente.
- El uso de complejos de boronato y Selectfluor II ofrece una herramienta valiosa para la fluoración estereoselectiva.
- El atrapamiento de radicales es beneficioso para mejorar el resultado estereoquímico de la reacción.
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