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Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Protonación asimétrica catalítica de las iminas de silil ceteno
Joyram Guin1, Georgy Varseev, Benjamin List
1Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|February 1, 2013
Resumen
Los ácidos fósforicos quirales catalizan la protonación enantioselectiva de las iminas de sililceteno. Este método eficiente transforma los sustratos racémicos en nitriles enriquecidos con enantio enriquecidos valiosos utilizando metanol.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Catalización asimétrica por catálisis asimétrica.
Sus antecedentes:
- Las iminas de sililceteno son versátiles intermediarios sintéticos.
- La síntesis enantioselectiva de nitriles sigue siendo un desafío importante en la química orgánica.
Objetivo del estudio:
- Desarrollar un método catalítico eficiente para la protonación enantioselectiva de las iminas de sililceteno.
- Para acceder a nitriles altamente enriquecidos con enantio de precursores racémicos fácilmente disponibles.
Principales métodos:
- Protonación asimétrica catalítica mediante el uso de ácidos fósforicos quirales (TRIP o STRIP).
- Utilizó metanol como fuente de protones y aceptor de sililo.
- Investigó el alcance de la reacción con varias iminas de sililceteno racémica sustituida.
Principales resultados:
- Se logra una alta eficiencia catalítica y enantioselectividad en la reacción de protonación.
- Transformó con éxito una serie de iminas sustituidas de sililceteno en los correspondientes nitriles.
- Productos obtenidos con un alto exceso enantiomérico (ee).
Conclusiones:
- El protocolo desarrollado proporciona una ruta novedosa y efectiva para los nitriles enriquecidos con enantio.
- La catálisis con ácido fosfórico quiral ofrece una poderosa estrategia para las reacciones de protonación asimétrica.
- Este método expande la utilidad sintética de las iminas de sililceteno en las transformaciones enantioselectivas.
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