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Borilación inducida por luz visible de los enlaces C-O, C-N y C-X
Shengfei Jin1, Hang T Dang1, Graham C Haug1
1Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States.
Journal of the American Chemical Society
|January 4, 2020
Resumen
Este estudio introduce un nuevo método de borilación fotocatalítico sin metal que utiliza la luz visible. La plataforma sintetiza eficientemente diversos boronatos de varios sustratos, incluidos los enlaces C-O desafiantes.
Área de la Ciencia:
- Química orgánica
- Fotocatálisis
- Metodología sintética
Sus antecedentes:
- Los ácidos borónicos son grupos funcionales vitales y precursores en la síntesis orgánica.
- Los métodos de borilación fotocatalíticos de luz visible existentes carecen de un amplio alcance de sustrato, especialmente para los enlaces fuertes de C-O.
Objetivo del estudio:
- Desarrollar una plataforma general de borilación fotocatalítica inducida por luz visible y libre de metales.
- Para permitir la berilización de una amplia gama de sustratos, incluidos los fenoles, las anilinas y los haloarenos.
Principales métodos:
- Fotocatálisis inducida por luz visible utilizando la fenotiazina como fotocatalizador orgánico.
- Mecanismo de transferencia de electrones acoplado a protones para la reducción de un solo electrón de sustratos ricos en electrones.
- Demostración de la tolerancia del grupo funcional con moléculas complejas.
Principales resultados:
- Borilación exitosa de derivados de fenol y anilina ricos en electrones, cloroarenos y otros haloarenos.
- Excelente tolerancia del grupo funcional observada en una variedad de sustratos estructuralmente complejos.
- Se logró una reducción de un solo electrón de los derivados del fenol inducida por la luz visible que antes no se podía lograr.
Conclusiones:
- Se ha establecido una plataforma de borilación fotocatalítica general y eficiente sin metales.
- La fenotiazina cataliza efectivamente la borilación de diversos sustratos a través de un mecanismo de transferencia de electrones acoplado a protones.
- La interacción fotocatalizador-base es crítica para el éxito de la reacción.
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