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Arilación catalizada por el paladio de aniones de sulfenato de alquilo

Tiezheng Jia¹, Mengnan Zhang¹, Hui Jiang¹

¹Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania , 231 S. 34th St., Philadelphia, Pennsylvania 19104-6323, United States.

Journal of the American Chemical Society

|October 14, 2015

Resumen

Una nueva reacción catalizada por paladio sintetiza eficientemente sulfóxidos de alquilo de arilo a partir de aniones de sulfenato. Este método utiliza una estrategia suave desencadenada por fluoruro, superando los desafíos asociados con los compuestos sensibles a las bases.

Área de la Ciencia:

Química orgánica
Química organometálica
Catálisis

Sus antecedentes:

Las reacciones de acoplamiento cruzado catalizadas por el paladio son vitales en la síntesis orgánica.
La síntesis de sulfóxidos de alquilo de arilo es un desafío debido a la sensibilidad de los productos intermedios.
Los métodos existentes a menudo requieren condiciones duras incompatibles con los grupos funcionales sensibles.

Objetivo del estudio:

Desarrollar un nuevo método catalizado por el paladio para la síntesis de sulfóxido de alquilo de arilo.
Abordar el desafío de la sensibilidad a las bases en la química de los sulfóxidos.
Para lograr altos rendimientos y quimioselectividad en la arilación de aniones sulfenados.

Principales métodos:

Generación de aniones de sulfenato de alquilo a través de una eliminación desencadenada por fluoruro de los sulfóxidos de alquilo 2- ((trimetilesil) etilo.
Arilación catalizada por el paladio utilizando bromuros o cloruros de arilo.
El uso de ligandos de fosfina monodentados voluminosos (SPhos y Cy-CarPhos) con catalizadores de paladio

Principales resultados:

Se obtuvieron altos rendimientos de sulfóxidos de alquilo de arilo.
El método superó con éxito la fragmentación térmica y los problemas de eliminación promovidos por la base.
Se observó una excelente quimioselectividad en presencia de grupos funcionales de anilina y fenol.

Conclusiones:

Se ha establecido una arylación única y efectiva catalizada por el paladio de aniones de sulfenato de alquilo.
La estrategia desencadenada por el fluoruro proporciona una ruta suave para acceder a valiosos sulfóxidos de alquilo de arilo.
Esta metodología ofrece una amplia tolerancia de grupo funcional, ampliando su utilidad sintética.

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