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Acceso modular a lactamas de tamaño medio a grande a través de la activación de enlaces C-C de los carbonilos no

Shan Yuan¹, Qifan Guan¹, Shican Peng¹

¹Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education of China, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan 410081, China.

Journal of the American Chemical Society

|August 29, 2025

Resumen

Este estudio introduce un nuevo método para sintetizar lactamas de tamaño medio a grande mediante la activación de cetonas no tensadas. El enfoque incorpora eficientemente átomos de nitrógeno, superando las limitaciones de los reordenamientos tradicionales.

Área de la Ciencia:

Química orgánica
Química sintética
Química medicinal

Sus antecedentes:

Los reordenamientos clásicos de Beckmann y Schmidt para la conversión de cetona a lactama tienen limitaciones.
Estos métodos se enfrentan a desafíos de regioselectividad y solo permiten la incorporación de nitrógeno único.

Objetivo del estudio:

Desarrollar un método eficiente para la síntesis de lactamas de tamaño medio a grande.
Superar las limitaciones de las reacciones de reordenamiento existentes para la síntesis de lactamo.

Principales métodos:

Se utilizó la inserción migratoria de alquinos para la activación del enlace carbono-carbono (C-C) de cetonas no tensadas.
Se utilizan derivados de la ortoalquinylanilina fácilmente disponibles para su incorporación regioselectiva.

Principales resultados:

Se ha logrado la formación regioselectiva de varios lactamos de tamaño medio y grande de manera modular.
Se ha demostrado una excepcional generalidad del sustrato y una buena tolerancia del grupo funcional.
Aplicó con éxito la metodología para modificar moléculas biorrelevantes, incluida la transferencia efectiva de quiralidad axial.

Conclusiones:

El método de inserción de alquinos desarrollado proporciona una ruta eficiente a lactamas de tamaño medio a grande.
Esta nueva estrategia ofrece ventajas sobre las reorganizaciones clásicas, incluida una mejor regioselectividad y la incorporación de nitrógeno.
La metodología muestra una amplia aplicabilidad en la síntesis y modificación de compuestos biológicamente relevantes.

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