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Fluoración de ésteres arilborónicos habilitados por catálisis redox de bismuto
Oriol Planas1, Feng Wang1, Markus Leutzsch1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany.
Science (New York, N.Y.)
|January 18, 2020
Resumen
Este estudio introduce nuevos complejos de bismuto capaces de reacciones similares a las de los metales de transición, lo que permite una fluoración eficiente del éster borónico de arilo a través de un ciclo redox de bismuto (III) /bismuto (V).
Área de la Ciencia:
- Química organometálica
- Catálisis
- Química de la fluoración
Sus antecedentes:
- La catálisis tradicional de bismuto utiliza la acidez de Lewis en un estado de oxidación fijo.
- Exploración limitada de las capacidades redox del bismuto en ciclos catalíticos.
- Necesidad de nuevos sistemas catalíticos para la formación selectiva de enlaces C-F.
Objetivo del estudio:
- Desarrollar nuevos complejos de bismuto que exhiban una reactividad más allá de la acidez de Lewis tradicional.
- Establecer un sistema catalítico basado en el bismuto para la fluoración de ésteres de arilo borónico.
- Para aclarar el mecanismo de la reacción de fluoración mediada por bismuto.
Principales métodos:
- Síntesis y caracterización de nuevos complejos de bismuto.
- Optimización de ligandos utilizando una fracción de sulfoxina.
- Estudios mecanicistas que incluyen análisis cristalográfico y seguimiento de la reacción.
- Pruebas catalíticas para la fluoración del éster de boro arilico.
Principales resultados:
- Se han demostrado complejos de bismuto capaces de adición oxidativa, eliminación reductiva y transmitación.
- Se identificó un catalizador de bismuto ligado a la sulfoximina activo para la fluoración del éster borónico de arilo.
- Se estableció un ciclo redox de bismuto (III) /bismuto (V) como la vía mecanicista clave.
- Los datos cristalográficos proporcionaron información sobre las estructuras de los principales productos intermedios del bismuto.
Conclusiones:
- Los nuevos complejos de bismuto pueden imitar la reactividad del metal de transición, expandiendo la utilidad catalítica del bismuto.
- El catalizador desarrollado permite la formación eficiente de enlaces C-F a través de un centro de bismuto redox activo.
- La comprensión del ciclo redox de bismuto es crucial para el diseño de futuros catalizadores basados en bismuto.
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