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La fluoroariación intermolecular asimétrica dirigida catalizada por el paladio de los estirenos

Eric P A Talbot¹, Talita de A Fernandes, Jeffrey M McKenna

¹Novartis Institutes for Biomedical Research , Horsham,West Sussex, RH12 5AB, United Kingdom.

Journal of the American Chemical Society

|March 13, 2014

Resumen

Los investigadores desarrollaron un nuevo método para crear compuestos quirales monofluorados utilizando catálisis de paladio. Esta reacción de tres componentes ofrece una forma suave y eficiente de sintetizar valiosos enlaces sp3 C-F.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Fluoración Química de la fluoración

Sus antecedentes:

La fluoración directa de C-H sigue siendo un desafío significativo en la síntesis orgánica.
La catálisis asimétrica es crucial para producir compuestos enantioméricamente puros.
El desarrollo de métodos catalíticos para la formación de enlaces C-F es muy buscado.

Objetivo del estudio:

Desarrollar una fluoro-arilación directa asimétrica catalítica suave y eficiente de los estirenos.
Para sintetizar compuestos quirales monofluorados con alto rendimiento y enantioselectividad.
Para aclarar el mecanismo de reacción que involucra un intermediario de paladio (IV) -fluoruro.

Principales métodos:

Reacción de acoplamiento de tres componentes catalizada con paladio.
Utilizado Selectfluor como fuente de flúor.
Empleó estirenos y ácidos borónicos como socios de acoplamiento.

Principales resultados:

Se obtienen buenos rendimientos de compuestos quirales monofluorados.
Se obtiene un alto exceso enantiomérico (ee) en los productos.
Sintetizó con éxito enlaces C-F sp3 a través de la fluoro-arilación catalítica asimétrica.

Conclusiones:

Se ha establecido una nueva y leve asimetría catalítica fluoro-arilación directa directa de estirenos.
El método desarrollado proporciona acceso a valiosas moléculas quirales monofluoradas.
Un mecanismo propuesto que involucra un intermediario Pd(IV) -fluoruro explica la transformación observada.

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