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Endo-hidroamidación intramolecular selectiva habilitada por catálisis de NiH que incluye isomerización de

Hoonchul Choi^1,2, Xiang Lyu^1,2, Dongwook Kim^1,2

¹Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea.

Journal of the American Chemical Society

|May 27, 2022

Resumen

Este estudio introduce una nueva reacción de hidroamidación intramolecular catalizada por hidróxido de níquel. El método logra una excelente endo-selectividad para la síntesis de valiosas enamidas cíclicas, incluidos los anillos azacíclicos más grandes.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La hidroamidación intramolecular de alquina es clave para la síntesis de la enamida cíclica.
El logro de un control de región preciso, especialmente la endociclización para anillos más grandes, sigue siendo un desafío.

Objetivo del estudio:

Desarrollar un método catalizado por NiH para la hidroamidación intramolecular altamente endoselectiva.
Para sintetizar enamidas endocíclicas de seis a ocho miembros con un amplio alcance.

Principales métodos:

Hidroamidación intramolecular catalizada por hidróxido de níquel (NiH) de las dioxazolonas de alquinyl.
Estudios mecanicistas que incluyen la catálisis del Ni (I), la sinhidronicelación y la isomerización del alquenil níquel.

Principales resultados:

Se obtiene una excelente endo-selectividad en la reacción de hidroamidación.
Sintetizó una variedad de enamidas endocíclicas de seis a ocho miembros.
Elucidado el mecanismo, incluida una isomerización clave de alquenilníquel a través de un estado de transición de vinilo eta-2.

Conclusiones:

El protocolo catalizado por NiH desarrollado proporciona una ruta robusta a las enamidas endocíclicas.
Las ideas mecanicistas, particularmente el paso de isomerización, avanzan en la comprensión de las reacciones de hidroamidación.
Las enamidas sintetizadas sirven como precursores valiosos para andamios delta-lactámicos altamente funcionales.

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