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Problemático acoplamiento de Ar-F-Alquinilo con Arilos Fluorados. Desde el éxito parcial con los estananos de

Guillermo Marcos-Ayuso¹, Marconi N Peñas-Defrutos^1,2, Ana M Gallego¹

¹IU CINQUIMA/Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, Valladolid E-47071, Spain.

Journal of the American Chemical Society

|December 21, 2022

Resumen

La síntesis de compuestos fluorados de arilo-alquinilo es un reto. Los nuevos métodos catalíticos superan las limitaciones de las reacciones anteriores, lo que permite una síntesis eficiente de estos valiosos compuestos y acoplamientos relacionados.

Área de la Ciencia:

Química orgánica
Catálisis
Química del fluor

Sus antecedentes:

Los acoplamientos tradicionales de Sonogashira y Shirakawa-Hiyama son ineficientes para sintetizar compuestos de arilo-alquinilo fluorados.
Los métodos existentes tienen bajos rendimientos y no son adecuados para sustratos fluorados con deficiencia de electrones.

Objetivo del estudio:

Investigar las limitaciones de los métodos catalíticos actuales para la síntesis de compuestos arilo-alquinílicos.
Desarrollar protocolos catalíticos novedosos y altamente eficientes para la síntesis de compuestos fluorados de arilo-alquinilo.
Explorar la aplicación de estos nuevos protocolos para las reacciones de acoplamiento alquinilo-alquinilo.

Principales métodos:

Análisis detallado de los mecanismos de reacción, incluida la identificación de los subproductos y la aclaración de las vías de reacción concurrentes.
Desarrollo y optimización de nuevos sistemas catalíticos que utilicen ligandos y condiciones de reacción específicas.
Aplicación de protocolos desarrollados para sintetizar una serie de compuestos arilo-alquiniles fluorados y realizar reacciones de homoacoplamiento/heteroacoplamiento.

Principales resultados:

Descubiertos subproductos no declarados anteriormente y ciclos de reacción coexistentes en los métodos existentes.
Se han identificado factores clave que contribuyen a la ineficiencia de los métodos convencionales con arilos fluorados.
Desarrolló nuevos protocolos catalíticos que logran rendimientos casi cuantitativos para la síntesis de compuestos Ar-F-alquinilo.
Demostró la alta eficiencia de los nuevos protocolos para el homoacoplamiento y el heteroacoplamiento alquinilo-alquinilo.

Conclusiones:

Se ha logrado una comprensión completa de las complejidades de los sistemas de aril/alquinilstanano.
Las estrategias catalíticas desarrolladas proporcionan soluciones eficientes y versátiles para la síntesis de compuestos arilo-alquinílicos fluorados.
Los nuevos protocolos ofrecen ventajas significativas sobre los métodos existentes, permitiendo amplias aplicaciones en la síntesis orgánica.

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