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Trifluorometilación y alquilación innata de aromáticos, libres de catalizadores y neutros en cuanto a redox,

Peng Liu^1,2, Wenbo Liu¹, Chao-Jun Li¹

¹Department of Chemistry and FQRNT Centre for Green Chemistry and Catalysis, McGill University , 801 Sherbrooke St. W., Montreal, Quebec H3A 0B8, Canada.

Journal of the American Chemical Society

|October 3, 2017

Resumen

Este estudio introduce un nuevo método libre de catalizadores para la creación de radicales alquilo utilizando la luz, que es útil para la funcionalización de compuestos aromáticos. Este enfoque innovador evita las etapas oxidativas o reductoras tradicionales, ofreciendo una forma más simple de lograr la trifluorometilación y la alquilación.

Área de la Ciencia:

Química orgánica
La fotoquímica
Reacciones radicales

Sus antecedentes:

La alquilación Minisci es un método clave para funcionalizar compuestos aromáticos utilizando radicales alquilo.
Los métodos existentes para generar radicales alquilo se basan en vías oxidativas o reductoras, que pueden ser limitantes.
Se necesita una estrategia nueva y eficiente para la generación de radicales alquilo.

Objetivo del estudio:

Desarrollar un nuevo protocolo libre de catalizadores y neutro en oxígeno para la generación de radicales alquilo.
Aplicar este método para la trifluorometilación y la alquilación general de los arenos.
Identificar nuevos reactivos asistidos por luz para reacciones radicales.

Principales métodos:

Utilizó el concepto de Norrish tipo I para la generación de radicales alquilo.
Se empleó un protocolo de reacción asistido por luz, neutro en oxígeno y libre de catalizadores.
Probado el protocolo para la trifluorometilación y la alquilación general de varios arenes.

Principales resultados:

Se generaron con éxito radicales alquilo sin pasos oxidativos o reductores tradicionales.
Se obtienen buenos rendimientos en la trifluorometilación y la alquilación de arenas.
Compuestos nuevos identificados como reactivos eficaces de trifluorometilación y alquilación asistida por luz.

Conclusiones:

El protocolo desarrollado ofrece un avance significativo más allá de los métodos tradicionales para la generación de radicales alquilo.
Esta nueva estrategia es versátil y se adapta a varios grupos funcionales.
Los reactivos identificados muestran potencial para aplicaciones más amplias en la síntesis orgánica con radicales.

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