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Updated: Sep 12, 2025

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Acoplamiento cruzado reductivo asimétrico catalizado por hierro de ketiminas con yoduros de alquilo

Jiaxin Wang¹, Haohao Bai¹, Xinping Xi¹

¹Tianjin Key Laboratory of Structure and Performance for Functional Molecules, College of Chemistry, Tianjin Normal University, Tianjin 300387, P. R. China.

Journal of the American Chemical Society

|August 8, 2025

Resumen

Este estudio introduce un método catalizado por el hierro para crear aminoésteres y amidas quirales a partir de ketiminas y haluros de alquilo. El nuevo enfoque ofrece altos rendimientos y enantioselectividad para la síntesis de moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis estereoselectiva

Sus antecedentes:

La síntesis asimétrica de compuestos amino alfa-terciarios es crucial para los productos farmacéuticos.
El desarrollo de métodos catalíticos eficientes para la formación de enlaces C ((sp3) -C sigue siendo un desafío.

Objetivo del estudio:

Desarrollar una nueva reacción de acoplamiento cruzado reductivo asimétrico catalizado por Fe.
Para sintetizar ésteres y amidas amino alfa-terciarios enriquecidos con enantio.

Principales métodos:

Se utilizó un catalizador de trilato de hierro (II) disponible en el mercado con un ligando quiral de bisoxasolina-fosfina (NPN).
Se utiliza manganeso barato como reductor para la reacción de acoplamiento cruzado.
Investigó el mecanismo de reacción utilizando experimentos de reloj radical y espectrometría de masas de alta resolución.

Principales resultados:

Se ha logrado una síntesis eficiente de aminoésteres y amidas alfa-terciarios enriquecidos con enantio.
Compatibilidad demostrada con una amplia gama de yoduros alquilo primarios y secundarios.
Muestra altos rendimientos, excelente enantioselectividad y excepcional tolerancia al grupo funcional.

Conclusiones:

El protocolo desarrollado permite la decoración en etapa tardía de moléculas complejas y la construcción de heterociclos con estereocentros cuaternarios.
El estudio pone de relieve el potencial de la catálisis quiral del hierro en las transformaciones radicales estereoselectivas.
Se ha establecido una vía de transferencia de electrones individuales (SET) que involucra el ciclo redox Fe (I) / Fe (II) / Fe (III) y las especies de radicales alquilo.

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