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Homólisis desaciladora de cetonas C-C enlaces: simplificación de las transformaciones de productos naturales

Michal Šimek¹, Sujit Mahato¹, Brady W Dehnert¹

¹Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California 90095-1569, United States.

Journal of the American Chemical Society

|January 8, 2025

Resumen

Este estudio introduce un nuevo método desacilante para la escisión de enlaces carbono-carbono en cetonas alifáticas. Esta versátil estrategia de fragmentación radical permite la diversificación molecular y la síntesis de moléculas complejas.

Área de la Ciencia:

Química orgánica
Química sintética
La Química Radical

Sus antecedentes:

La escisión del enlace C-C homolítico es clave para la diversificación molecular.
La fragmentación radical de los enlaces alfa-C-C en las cetonas es sintéticamente desafiante.

Objetivo del estudio:

Desarrollar una estrategia desacilante ampliamente aplicable para la escisión homolítica de cetonas alifáticas.
Para permitir las transformaciones de cetonas en radicales libres centrados en C para una mayor funcionalidad.

Principales métodos:

Activación de cetonas mediante el uso de peróxido de hidrógeno para formar dihidroperoxidos de gemas.
Reducción por transferencia de electrones mediada por complejos metálicos de baja valencia.
Captura selectiva de radicales alquilo generados con un radicófilo elegido.

Principales resultados:

Se ha demostrado la escisión exitosa de los enlaces alfa-C-C en varias cetonas alifáticas.
Radicales libres centrados en C generados a partir de cetonas, adecuados para procesos basados en radicales.
Se ha logrado la captura selectiva de radicales mediante acoplamiento catalítico.

Conclusiones:

La estrategia desacilante proporciona un método versátil y ampliamente aplicable para la funcionalización de cetonas.
El enfoque fue validado a través de la síntesis total de 14 productos naturales, un análogo y dos fármacos.
Este método ofrece una conversión controlada de cetonas, evitando reactivos complejos y permitiendo diversas aplicaciones.

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