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Acoplamiento oxidativo electroquímico enantioselectivo habilitado por TEMPO de aminas acíclicas secundarias con

Zhen-Hua Wang¹, Pei-Sen Gao¹, Xiu Wang¹

¹Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China.

Journal of the American Chemical Society

|September 17, 2021

Resumen

Este estudio introduce un método electroquímico para sintetizar derivados de aminoácidos a partir de aminas y cetonas. El proceso utiliza un mediador redox para la oxidación selectiva, logrando una alta selectividad sin aditivos agresivos.

Área de la Ciencia:

Química orgánica
La electroquímica
Metodología sintética

Sus antecedentes:

La síntesis asimétrica de derivados de aminoácidos es crucial para los productos farmacéuticos.
El desarrollo de métodos catalíticos eficientes y selectivos sigue siendo un desafío.
Los métodos electroquímicos ofrecen una alternativa sostenible a las rutas sintéticas tradicionales.

Objetivo del estudio:

Desarrollar un nuevo acoplamiento electroquímico asimétrico de aminas acíclicas secundarias con cetonas.
Para lograr una alta diastereoselectividad y enantioselectividad en la síntesis de derivados de aminoácidos.
Explorar el uso de radicales N-oxilo como mediadores redox en reacciones electroquímicas.

Principales métodos:

Reacción de acoplamiento asimétrico electroquímico.
Mecanismo de oxidación tipo Shono.
Utilizando los radicales N-oxilo como mediadores redox.
Estudios mecánicos relacionados con la reducción de protones en el cátodo.

Principales resultados:

Síntesis exitosa de derivados de aminoácidos con buena o excelente diastereoselectividad y enantioselectividad.
Oxidación selectiva del sustrato sobre el producto utilizando radicales N-oxilo, a pesar de una sutil diferencia de potencial.
Compatibilidad demostrada del grupo funcional debido a la ausencia de aditivos estequiométricos.
Prevención de la racemización mediada por protones del producto mediante reducción catódica.

Conclusiones:

El método electroquímico desarrollado proporciona una vía eficiente para obtener derivados de aminoácidos enriquecidos enantioméricamente.
El uso de radicales N-oxilo ofrece un control preciso sobre el proceso de oxidación.
Esta metodología presenta un enfoque sostenible y versátil para la síntesis de compuestos orgánicos valiosos.

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