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Migración radical del arilo del boro al carbono
Dinghai Wang1, Christian Mück-Lichtenfeld1, Constantin G Daniliuc1
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|June 21, 2021
Resumen
Este estudio introduce la migración radical del 1,5-arilo del boro al carbono en los complejos de boronato de arilo, una nueva transformación orgánica. Este método permite el acceso a diversos productos arilados en condiciones suaves con una alta diastereoselectividad.
Área de la Ciencia:
- Química orgánica
- Reacciones radicales
- Química del organoboron
Sus antecedentes:
- La migración radical de arilo es una transformación orgánica conocida que involucra la migración de grupos arilo.
- Estudios anteriores han informado de migraciones que involucran elementos como N, O, Si, P, S, Sn, Ge y Se.
- La migración radical de arilo desde un centro de boro no se ha documentado anteriormente.
Objetivo del estudio:
- Para presentar el primer informe de la migración del radical 1,5-arilo del boro al carbono.
- Demostrar la utilidad de esta reacción en la síntesis de productos relacionados.
- Explorar el alcance y el mecanismo de esta nueva transformación.
Principales métodos:
- Generación de radicales centrados en el carbono a través de la adición radical a los complejos de alquenil aril boronato.
- Investigación de la migración del 1,5-arilo del boro al carbono.
- Generación in situ de complejos de boronato a partir de ésteres de ácido alquenilborónico y reactivos de litio arilo.
- Utilización de cálculos de DFT para apoyar el mecanismo propuesto.
Principales resultados:
- Demostración exitosa de la migración del radical 1,5-arilo desde el boro al carbono.
- Síntesis de ésteres 4-arilo-alquilborónicos con una alta diastereoselectividad.
- Facilitación de la síntesis divergente mediante la variación de la fracción de arilo.
- Factibilidad de desplazamientos analógicos de 1,4-arilo.
Conclusiones:
- La migración radical del 1,5-arilo desde el boro es una metodología sintética nueva y eficiente.
- La reacción ofrece una vía versátil para diversos ésteres alquilborónicos arilados.
- Los hallazgos amplían el alcance de las reacciones de migración de arilo radical conocidas.
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