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Un tipo de catalizador quiral C2 simétrico para la hidroaminación anti-Markovnikov altamente enantioselectiva

Lin Tang¹, Chaoren Shen¹, Shaoyu Hao¹

¹Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.

Journal of the American Chemical Society

|May 29, 2024

Resumen

Los investigadores desarrollaron nuevos catalizadores quirales de ariltiol para la organocatálisis asimétrica. Estos catalizadores permiten reacciones de transferencia de átomos de hidrógeno enantioselectivas, produciendo valiosos intermedios farmacéuticos con alta selectividad.

Área de la Ciencia:

Química orgánica
Catálisis asimétrica
La catálisis orgánica

Sus antecedentes:

Los catalizadores quirales son cruciales para la síntesis enantioselectiva.
Las reacciones asimétricas de transferencia de átomos de hidrógeno (HAT) son vitales en la organocatálisis.
El desarrollo de nuevos catalizadores quirales expande las capacidades sintéticas.

Objetivo del estudio:

Desarrollar una nueva clase de catalizadores quirales C2-simétricos de ariltiol.
Para establecer una reacción asimétrica de hidroaminación y ciclización de alqueno anti-Markovnikov.
Para investigar el mecanismo de control estéreo en estas reacciones.

Principales métodos:

Síntesis de nuevos catalizadores quirales C2-simétricos de ariltiol a partir de ésteres de lactato.
Aplicación de catalizadores en la hidroaminación-ciclización asimétrica de los alquenos de Markovnikov.
Utilizando experimentos de control y cálculos teóricos para estudios mecanicistas.

Principales resultados:

Síntesis exitosa de catalizadores quirales de ariltiol sin precedentes.
Establecimiento de una reacción asimétrica de hidroaminación-ciclización que produce piperidinas 3-sustituidas.
Se obtiene una enantioselectividad de moderada a alta en los productos de ciclización.
Racionalización del origen del control estéreo y los efectos espaciales de las fracciones de catalizador.

Conclusiones:

Los catalizadores de ariltiol quiral desarrollados son efectivos para las reacciones asimétricas de HAT.
La fácil síntesis y ajustabilidad de estos catalizadores ofrecen versatilidad.
Este trabajo proporciona información sobre el desarrollo de nuevos catalizadores quirales HAT y reacciones asimétricas.

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