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Hidrogenaciones asimétricas secuenciales catalizadas por Rh de 3-Amino-4-Cromonas a través de un proceso de

Yunnan Xu¹, Yicong Luo², Jianxun Ye¹

¹Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.

Journal of the American Chemical Society

|October 18, 2022

Resumen

Este estudio introduce un nuevo método catalizado por Rh para la hidrogenación asimétrica de 3-amino-4-cromonas, logrando una resolución cinética dinámica en condiciones neutras. El proceso produce valiosos (S,R) -3-amino-4-cromanoles con una pureza y selectividad excepcionales.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Los 3-amino-4-cromanoles son moléculas bioactivas importantes.
Los métodos anteriores para su síntesis a menudo carecen de eficiencia o selectividad.
La hidrogenación asimétrica es una herramienta clave para crear compuestos quirales.

Objetivo del estudio:

Para desarrollar una nueva hidrogenación asimétrica secuencial catalizada por Rh de 3-amino-4-cromonas.
Para lograr la resolución cinética dinámica en condiciones neutrales por primera vez.
Proporcionar una vía práctica para los cromanoles enantioméricos puros (S, R) -3-amino-4.

Principales métodos:

Hidrogenación asimétrica secuencial mediante un catalizador Rh.
Resolución cinética dinámica bajo condiciones neutras.
Estudios mecanicistas que incluyen experimentos de control y cálculos DFT.

Principales resultados:

Se obtuvieron altos rendimientos (hasta el 98%) y excelentes enantioselectividades (hasta el 99,9% ee) y diastereoselectividades (hasta el 20:1 dr).
Se identificó una vía de estereomutación sin precedentes para la resolución cinética dinámica.
El protocolo es escalable a cantidades de gramos con baja carga de catalizador.

Conclusiones:

Se ha establecido un método nuevo y eficiente para la síntesis de (S,R) -3-amino-4-cromanoles.
La visión mecanicista de la vía de estereomutación avanza en la comprensión de la resolución cinética dinámica.
Este protocolo ofrece un enfoque práctico para la síntesis de cromanolos y derivados bioactivos.

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