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Hidroaminación regionalizada y enantioselectiva catalizada por níquel de alquenos no activados utilizando grupos

Changseok Lee^1,2, Hyung-Joon Kang^1,2, Huiyeong Seo^1,2

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

Journal of the American Chemical Society

|May 11, 2022

Resumen

Este estudio presenta un nuevo método catalizado por níquel para crear aminas quirales a partir de alquenos simples. El proceso es altamente selectivo y útil para la síntesis de moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Las aminas quirales son bloques de construcción valiosos en productos farmacéuticos y materiales.
La hidroaminación catalítica directa de alquenos no activados es un desafío pero muy deseable.
Los métodos existentes a menudo carecen de selectividad o requieren sustratos prefuncionalizados.

Objetivo del estudio:

Desarrollar una hidroaminación catalítica altamente enantio y regioselectiva de alquenos no activados.
Para utilizar alquenos fácilmente disponibles que contienen amidas o ésteres nativos.
Proporcionar acceso modular a los derivados de aminas enriquecidos con enantio.

Principales métodos:

Reacción de hidroaminación catalizada por níquel.
Uso de un catalizador quiral de níquel unido a la bisoxazolina.
El uso de alquenos terminales y internos no activados con grupos de coordinación débil.
Estudios mecanicistas que incluyen coordinación de carbonilo.

Principales resultados:

Se obtiene una alta enantioselectividad y regioselectividad en la hidroaminación.
Se ha demostrado el éxito con alquenos no activados terminales e internos.
Mostró un amplio alcance para los socios de acoplamiento de aminas.
Se confirmó el papel de la coordinación carbonila en la selectividad del catalizador.

Conclusiones:

Desarrolló una hidroaminación catalizada por Ni versátil y eficiente de alquenos no activados.
El método permite la funcionalización en etapa tardía y el acceso a los aminoácidos y las diaminas quirales β o γ.
Los conocimientos mecanicistas destacan la importancia de la coordinación del sustrato para la selectividad.

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