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A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
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Hidrogenación de transferencia asimétrica de carbonitrilos α-sustituidos-β-ceto mediante resolución cinética dinámica
Fangyuan Wang1,2, Tilong Yang2, Ting Wu3
1School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, People's Republic of China.
Journal of the American Chemical Society
|February 2, 2021
Resumen
Este estudio introduce un método catalítico para la reducción de ceto carbonitrilo, creando moléculas complejas con alta precisión. Este eficiente proceso produce valiosos productos farmacéuticos intermedios.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Síntesis asimétrica
Sus antecedentes:
- El desarrollo de métodos catalíticos eficientes para la construcción de moléculas quirales es crucial en la síntesis orgánica.
- Los carbonitrilos α-sustituidos-β-ceto son bloques de construcción versátiles para estructuras orgánicas complejas.
Objetivo del estudio:
- Desarrollar un protocolo catalítico para la reducción enantio y diastereoselectiva de los carbonitrilos α-substituidos-β-ceto.
- Para construir andamios β-hidroxi-carbonitrilo con dos centros estereogénicos contiguos al mismo tiempo.
Principales métodos:
- Proceso de hidrogenación por transferencia asimétrica de resolución cinética dinámica (DKR-ATH).
- Los cálculos de la Teoría Funcional de Densidad (DFT) para racionalizar la diastereoselectividad.
Principales resultados:
- Altos rendimientos (94%-98%) para una amplia gama de sustratos.
- Excelentes enantio y diastereoselectividades (hasta > 99% ee, > 99:1 dr).
- Síntesis exitosa de los intermediarios farmacéuticos para la ipenoxazona y el tapentadol.
Conclusiones:
- El protocolo DKR-ATH descrito proporciona una ruta eficiente hacia los β-hidroxicarbonitrilos quirales.
- La metodología permite un acceso rápido a importantes productos farmacéuticos intermedios.
- El estudio ofrece información sobre el control estereoquímico de la reacción a través del análisis DFT.
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