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Desaromatización en tándem y alquilación aliloide enantioselectiva de las piridinas

Steffen Greßies¹, Lars Süße¹, Tyler Casselman¹

¹Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.

Journal of the American Chemical Society

|May 22, 2023

Resumen

Este estudio introduce una nueva reacción de un solo recipiente para crear tetrahidropiridinas protegidas por N con alta enantioselectividad. El método utiliza la catálisis del iridio y el paladio para la síntesis eficiente de las valiosas tetrahidropiridinas sustituidas por C-3.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Las tetrahidropiridinas son importantes bases en la química medicinal.
El acceso a las tetrahidropiridinas sustituidas C-3 enriquecidas con enantio es un desafío.
La química tradicional de la piridina ofrece una selectividad nucleofílica limitada.

Objetivo del estudio:

Desarrollar una síntesis nueva, eficiente y enantioselectiva de tetrahidropiridinas protegidas por N.
Establecer una secuencia de reacción telescópica que supere las limitaciones de reactividad de la piridina inherentes.
Proporcionar acceso a valiosos derivados de tetrahidropiridina sustituidos por C-3.

Principales métodos:

Se empleó una secuencia de reacción de una olla en varios pasos.
La 1,2-hidrosilación dearomativa catalizada por el iridio de las piridinas.
Alquilación alilica asimétrica catalizada por el paladio utilizando enaminas de N-sililo como nucleófilos.

Principales resultados:

Se ha logrado una enantioselectividad sobresaliente de hasta el 97% en la síntesis de tetrahidropiridinas N-protegidas.
Utilizó con éxito las enaminas de N-sililo como nuevos nucleófilos en una reacción catalizada por paladio.
Desarrolló un proceso telescópico que permite la síntesis eficiente de las tetrahidropiridinas sustituidas por C-3.

Conclusiones:

La estrategia de un solo recipiente desarrollada proporciona una nueva y poderosa vía para obtener tetrahidropiridinas enriquecidas con enantio.
Esta metodología expande la utilidad sintética de las piridinas en la catálisis asimétrica.
El enfoque ofrece una herramienta valiosa para acceder a estructuras complejas de tetrahidropiridina.

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