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Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

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Hidrogenación asimétrica a través de la captura de los intermediarios activos generados por el reordenamiento de

Chang-Bin Yu¹, Wen-Xue Huang, Lei Shi

¹State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China.

Journal of the American Chemical Society

|October 30, 2014

Resumen

Un nuevo método de hidrogenación asimétrica catalizado por el paladio produce eficientemente aminas exocíclicas quirales a partir de N-sulfonilo aminoalcoholes cíclicos. Este avance ofrece una nueva ruta para la síntesis de valiosos compuestos quirales de aminas.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

Las aminas exocíclicas quirales son bloques de construcción importantes en los productos farmacéuticos.
Los métodos existentes para sintetizar aminas quirales pueden ser limitados en alcance o eficiencia.

Objetivo del estudio:

Desarrollar un método catalítico eficiente para acceder a las aminas quirales exocíclicas.
Explorar el uso de la hidrogenación asimétrica junto con el reordenamiento de aza-Pinacol.

Principales métodos:

Hidrogenación asimétrica catalizada por el paladio.
Generación in situ de intermedios activos a través de la reorganización aza-Pinacol catalizada por ácido.
Hidrogenación de aminoalcoholes N-sulfonilo cíclicos de tres, cuatro y cinco miembros.

Principales resultados:

Desarrollo exitoso de una hidrogenación asimétrica eficiente catalizada por paladio.
Se logran altas enantioselectividades (hasta el 98% ee) para las aminas quirales exocíclicas.
Alcance de sustrato demostrado que incluye aminoalcoholes cíclicos N-sulfonilo de diferentes tamaños de anillo.

Conclusiones:

El método desarrollado proporciona un acceso eficiente a valiosas aminas quirales exocíclicas.
Este trabajo amplía el alcance de aplicación de la hidrogenación asimétrica.
La estrategia ofrece una nueva ruta sintética para la síntesis de aminas quirales.

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