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Electrocatálisis emparejada asimétrica: acoplamiento enantioselectivo de olefinas y sulfoniliminas

Cheng Huang¹, Yongsheng Tao¹, Xiyang Cao¹

¹The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, P. R. China.

Journal of the American Chemical Society

|December 19, 2023

Resumen

Este estudio introduce la electrólisis asimétrica emparejada para sintetizar aminas quirales. Este nuevo método acopla eficientemente las reacciones en ambos electrodos, creando valiosas moléculas quirales con alta selectividad.

Área de la Ciencia:

Química orgánica
La electro-síntesis
Catálisis

Sus antecedentes:

La electrocatálisis asimétrica es una herramienta poderosa para sintetizar moléculas quirales.
La activación simultánea de los reactivos en ambos electrodos (electrolisis emparejada) es energéticamente eficiente pero desafiante.
El desarrollo de nuevos sistemas catalíticos para la electrólisis emparejada es crucial para la síntesis sostenible.

Objetivo del estudio:

Para presentar el primer acoplamiento asimétrico olefinas-sulfonilminas mediante electrocatálisis emparejada.
Demostrar un nuevo sistema catalítico para la activación simultánea de reactivos en ambos electrodos.
Para sintetizar productos de aminas quirales con un estereocentro de carbono tetrasubstituido.

Principales métodos:

Utilizando la transferencia de átomos de hidrógeno catalizados por cobalto en el ánodo.
Utilizando reducción de sulfonilímina catalizada por níquel en el cátodo.
Reacciones anódicas y catódicas de acoplamiento sin fisuras en una configuración de electrólisis emparejada.

Principales resultados:

Logró el primer acoplamiento asimétrico olefina-sulfonilmina utilizando electrocatálisis emparejada.
Se han sintetizado con éxito productos de aminas quirales con un estereocentro de carbono tetrasubstituido.
Se obtiene una elevada enantioselectividad, de hasta el 96%, lo que demuestra la eficacia del sistema.

Conclusiones:

El sistema de electrocatálisis emparejado desarrollado ofrece una vía eficiente y económica para la síntesis de aminas quirales.
Este trabajo supera el desafío de la activación simultánea del reactivo en ambos electrodos en electrocatálisis asimétrica.
La metodología proporciona una nueva estrategia para construir moléculas quirales complejas con alto estereocontrol.

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