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Desmetilación selectiva catalizada por níquel fotoinducida de las trialquilaminas utilizando bromuros como reactivos

Xiao Zhang¹, Yangyang Shen¹, Tomislav Rovis¹

¹Department of Chemistry, Columbia University, New York, New York 10027, United States.

Journal of the American Chemical Society

|February 1, 2023

Resumen

Este estudio introduce un método catalítico suave para la N-demetilación de las triquilaminas utilizando la catálisis de níquel fotoinducida y los bromuros C ((sp2)) como reactivos de transferencia de átomos de hidrógeno. Este enfoque ofrece una amplia compatibilidad de grupo funcional y selectividad de sitio para la derivación de moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
La fotoquímica

Sus antecedentes:

La N-desmetilación de las trialquilaminas es crucial, pero a menudo requiere condiciones severas y estrategias de protección.
Los métodos existentes carecen de eficiencia y amplia aplicabilidad para moléculas complejas.

Objetivo del estudio:

Desarrollar un método de desmetilación N leve, catalítico y directo para las triquilaminas.
Para permitir la derivación en etapa tardía de moléculas complejas con alta tolerancia de grupo funcional.

Principales métodos:

Utilizando la catálisis de níquel fotoinducida con bromuros de C ((sp2)) como reactivos de transferencia de átomos de hidrógeno (HAT).
Investigación de vías mecanicistas que involucran radicales C ((sp2) y abstracción de átomos de hidrógeno.
Utilizando el control estérico de los bromuros de C ((sp2)) para la selectividad del sitio.

Principales resultados:

Se consigue la N- desmetilación directa de las trialquilaminas en condiciones suaves.
Compatibilidad demostrada con un amplio grupo funcional, adecuada para sustratos complejos.
Mostró una excelente selectividad del sitio, distinguiendo entre las aminas alquilo y bencilo.

Conclusiones:

El enfoque HAT fotoinducido catalizado por níquel desarrollado proporciona una alternativa suave y eficiente para la desmetilación de N.
Este método es muy valioso para la funcionalización en etapa tardía en la síntesis de moléculas complejas.
La selectividad del sitio se puede controlar a través de las propiedades estéricas del reactivo de bromuro de C.

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