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Hidroacilación selectiva de radicales de Markovnikov catalizados por cobalto de alquenos no activados con

Benxiang Zhang¹, Jiayan He¹, Yi Li¹

¹Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

Journal of the American Chemical Society

|March 30, 2021

Resumen

Los nuevos reactivos de acilfosfonato permiten la hidroacilación de los alquenos catalizada por cobalto. Esta reacción produce eficientemente cetonas ramificadas bajo condiciones suaves, ofreciendo una herramienta sintética valiosa para la química orgánica.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los acilfosfonatos están surgiendo como reactivos versátiles en la síntesis orgánica.
La acilación radical ofrece una poderosa estrategia para la formación de enlaces carbono-carbono.
El desarrollo de métodos eficientes para la funcionalización de alquenos no activados sigue siendo un desafío clave.

Objetivo del estudio:

Desarrollar nuevos reactivos de acilfosfonato para la acilación radical.
Para establecer un protocolo catalizado por cobalto para la hidroacilación de alquenos no activados por Markovnikov.
Explorar el alcance y las limitaciones de la metodología desarrollada.

Principales métodos:

Síntesis de los acilfosfonatos de 5,5-dimetil-1,3,2-dioxofosfinanilo.
Reacción catalizada por cobalto de alquenos con acilfosfonatos bajo condiciones suaves.
Caracterización de los productos de reacción mediante técnicas espectroscópicas estándar.

Principales resultados:

Se logró una eficiente acilación de radicales intermoleculares de alquenos no activados.
La reacción se lleva a cabo en condiciones suaves a temperatura ambiente.
Se observó un amplio alcance en el sustrato y una excelente tolerancia del grupo funcional.
Las cetonas ramificadas se obtuvieron en rendimientos satisfactorios.

Conclusiones:

Los acilfosfonatos desarrollados son reactivos eficientes para la hidroacilación de Markovnikov catalizada por cobalto.
El protocolo proporciona una ruta suave y versátil a las cetonas ramificadas.
Se propone un mecanismo plausible que implique la transferencia de átomos de hidrógeno mediada por Co-H y la captura de radicales.

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