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BF₃-Catálisis de la fluorocarbamoilación intramolecular de las alquinas mediante el reciclado de haluros

E Ali McKnight¹, Ramon Arora², Ekadashi Pradhan¹

¹Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada.

Journal of the American Chemical Society

|May 12, 2023

Resumen

Una nueva reacción catalizada por trifluoruro de boro (BF3) permite la síntesis atómica económica de compuestos fluorados mediante la inserción de alquinas en enlaces C-F. Este método produce eficientemente valiosos 3- (fluorometileno) oxindoles y γ-lactamas con alta estereoselectividad.

Área de la Ciencia:

Química orgánica
Catálisis
Química del fluor

Sus antecedentes:

Las reacciones atómico-económicas son cruciales para la síntesis sostenible.
Los compuestos orgánicos fluorados tienen aplicaciones significativas en productos farmacéuticos y ciencias de los materiales.
El desarrollo de métodos eficientes para la funcionalización de los bonos C-F sigue siendo un desafío.

Objetivo del estudio:

Para reportar una nueva reacción de fluorocarbamoylación catalizada por el BF3.
Para permitir la inserción formal de alquinas en fuertes enlaces C-F.
Proporcionar acceso a los oxindoles y lactamos fluorados estereoselectivos.

Principales métodos:

Utilizando el trifluoruro de boro (BF3) como catalizador dual (fuente de fluoruro y activador del ácido de Lewis).
Utilizando como sustratos fluoruros de carbamoil atados al alquino.
Investigar los mecanismos de reacción a través de estudios experimentales y computacionales.

Principales resultados:

Se ha logrado una fluorocarbamoylación atómica económica mediante un mecanismo de reciclado de halogenuros.
Se han sintetizado 3- ((fluorometileno) oxindoles y γ-lactamas con una excelente estereoselectividad.
Derivados fluorados desarrollados de inhibidores conocidos de la proteína quinasa.
Elucidado un mecanismo escalonado que implica la ciclización y la transferencia de fluoruro.
Se observaron resultados estereoquímicos distintos para las oxindoles (isomerización Z-E) y las γ-lactamas (formación exclusiva de Z-isómero) debido a la diferencia de estabilización del estado de transición.

Conclusiones:

La reacción catalizada por BF3 desarrollada ofrece una nueva ruta poderosa para la funcionalización del enlace C-F.
El método proporciona acceso a valiosos compuestos heterocíclicos fluorados con estereoquímica controlada.
Comprender los matices mecanicistas es clave para controlar la estereoselectividad en las transformaciones relacionadas.

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