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Cicloadición alquino-azida catalizada por níquel enantioselectiva por resolución cinética dinámica
En-Chih Liu1, Joseph J Topczewski1
1Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States.
Journal of the American Chemical Society
|April 2, 2021
Resumen
Los investigadores desarrollaron la primera síntesis enantioselectiva de triazoles quirales utilizando cicloadición de alquina-azida catalizada por níquel (NiAAC). Este método ofrece una nueva ruta para bloques de construcción quirales valiosos, complementando las reacciones catalizadas por cobre existentes.
Área de la Ciencia:
- Química orgánica
- Química medicinal
- Catálisis
Sus antecedentes:
- El heterociclo de triazol es un isóster común para el enlace amídico en la química medicinal.
- Muchas amidas biológicamente relevantes son quirales, originadas en aminoácidos.
- El desarrollo de bloques de construcción quirales de triazol es crucial para el descubrimiento y desarrollo de fármacos.
Objetivo del estudio:
- Se informará de la primera síntesis enantioselectiva de triazoles 1,4,5-trisubstituidos.
- Establecer una cicloadición alquinoazida catalizada por níquel (NiAAC) como método para la síntesis asimétrica.
- Explorar una nueva vía de resolución cinética dinámica para la formación de triazol.
Principales métodos:
- Reacción de cicloadición de alquina-azida catalizada por níquel (NiAAC).
- Utilizando una reorganización espontánea [3,3]-sigmatrópica de las azidas alilicas para la resolución cinética dinámica.
- El uso de alquinas internas para generar productos de triazol 1,4,5-trisubstituidos.
Principales resultados:
- Se logró la primera reacción enantioselectiva de NiAAC para la síntesis de triazol.
- Se ha demostrado la formación de triazoles α-N-quirales mediante resolución cinética dinámica.
- Los productos NiAAC son complementarios a los que se obtienen típicamente mediante la cicloadición azida-alquina catalizada por cobre (CuAAC).
Conclusiones:
- El NiAAC enantioselectivo proporciona un método nuevo y eficiente para sintetizar triazoles quirales.
- El mecanismo de reacción probablemente implica un complejo de níquel monometálico distinto, que difiere de las vías de CuAAC.
- Este trabajo amplía la caja de herramientas sintéticas para acceder a compuestos heterocíclicos quirales con aplicaciones farmacéuticas potenciales.
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