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Reacciones electroquímicas enantioselectivas de activación de arilo C-H catalizadas por cobalto

Tristan von Münchow¹, Suman Dana¹, Yang Xu¹

¹Wöhler Research Institute for Sustainable Chemistry, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.

Science (New York, N.Y.)

|March 9, 2023

Resumen

Este estudio introduce la electrocatálisis catalizada por cobalto para reacciones enantioselectivas sostenibles, reemplazando a los metales preciosos y los oxidantes químicos. El método logra una alta selectividad en las activaciones de enlaces C-H y N-H, creando valiosos compuestos quirales.

Área de la Ciencia:

Química orgánica
La electroquímica
Catálisis

Sus antecedentes:

La síntesis enantioselectiva a menudo requiere metales de transición caros y oxidantes estequiométricos.
La electrocatálisis ofrece una alternativa sostenible al utilizar corriente eléctrica y evitar reactivos químicos agresivos.
La reacción de evolución del hidrógeno (HER) es un oxidante electrocatalítico prometedor para la química verde.

Objetivo del estudio:

Desarrollar un sistema electrocatalítico sostenible para la activación enantioselectiva del enlace arilo carbono-hidrógeno (C-H).
Sustituir los catalizadores de metales preciosos por cobalto abundante en la tierra para la oxidación asimétrica.
Para lograr una alta enantioselectividad en la anulación de enlaces C-H y N-H y en la síntesis de compuestos P-esterogénicos.

Principales métodos:

Utilizando cobalto como catalizador para las transformaciones redox enantioselectivas.
El uso de electrocatálisis junto con la reacción de evolución del hidrógeno (HER) como un oxidante sostenible.
Investigando las reacciones de activación arilo C-H enantioselectivas acopladas a HER de las amidas carboxílicas.

Principales resultados:

Se obtienen anulaciones altamente enantioselectivas de C-H y N-H de amidas carboxílicas, produciendo compuestos quirales puntuales y axialmente.
Se ha demostrado la preparación de varios compuestos estereogénicos de fósforo (P) mediante desimetrización electrocatalítica mediada por cobalto.
Con éxito sustituido costosos metales preciosos con cobalto para las reacciones de oxidación asimétrica.

Conclusiones:

La electrocatálisis mediada por cobalto proporciona un enfoque sostenible y eficiente para la síntesis enantioselectiva.
Esta metodología permite la construcción de moléculas quirales complejas, incluidos los compuestos P-esterogénicos.
El sistema desarrollado ofrece una alternativa más ecológica a los métodos tradicionales de catálisis asimétrica.

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