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Cianosilación estereoselectiva organocatalítica de las cetonas pequeñas
Hui Zhou1, Yu Zhou2, Han Yong Bae1,3
1Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany.
Nature
|May 4, 2022
Resumen
Los químicos desarrollaron nuevos organocatalizadores confinados que logran una alta enantioselectividad en la conversión de cetonas en cianohidrinas. Este avance rivaliza con la estereoselectividad enzimática para sustratos pequeños e imparciales.
Área de la Ciencia:
- Catálisis
- Química orgánica
- Estereoquímica
Sus antecedentes:
- Las enzimas exhiben una estereoselectividad sin paralelo debido a los sitios activos confinados, una característica que carece en los catalizadores químicos tradicionales.
- La cianosilación de cetonas para formar cianohidrinas es una reacción clave catalizada por varios agentes, incluidas las enzimas y los catalizadores químicos.
- El logro de una alta enantioselectividad en esta reacción con catalizadores químicos, especialmente para sustratos pequeños e imparciales, sigue siendo un desafío significativo.
Objetivo del estudio:
- Desarrollar organocatalizadores confinados de amplia aplicación para la cianosiliación altamente enantioselectiva de cetonas.
- Demostrar que los catalizadores químicos diseñados pueden igualar la estereoselectividad enzimática para sustratos pequeños.
Principales métodos:
- Desarrollo de nuevos organocatalizadores confinados.
- Aplicación de estos catalizadores a la cianosilación de cetonas aromáticas y alifáticas, incluida la 2-butanona.
- Se recomienda que se utilicen los siguientes métodos para determinar la enantioselectividad: En el caso de los
Principales resultados:
- Se ha logrado una cianosilación altamente enantioselectiva de diversas cetonas.
- Se ha demostrado una selectividad excepcional (98:2 e.r.) para productos farmacéuticamente relevantes.
- Demostró la eficacia de los organocatalizadores confinados, superando a otras clases de catalizadores, incluidos los biocatalizadores de ingeniería.
Conclusiones:
- Los organocatalizadores confinados pueden diseñarse para lograr niveles enzimáticos de estereoselectividad para sustratos pequeños e imparciales.
- Este avance ofrece una poderosa alternativa química al biocatálisis para la síntesis enantioselectiva.
- Los catalizadores desarrollados proporcionan una amplia aplicabilidad y una alta selectividad en la cianosilación de cetonas.
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