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Cómo las aminas primarias derivadas de alcaloides de cinchona controlan la fluoración electrofílica asimétrica de
1Department of Chemistry and Biochemistry, University of California, Los Angeles , 607 Charles E. Young Drive East, Los Angeles, California 90095-1569, United States.
Journal of the American Chemical Society
|June 27, 2014
Resumen
Se estudió el origen de la selectividad en la fluoración cíclica de cetonas. Los cálculos muestran que el anillo de siete miembros.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Química computacional es la química computacional.
Sus antecedentes:
- La α-fluorización enantioselectiva de las cetonas es crucial para la síntesis de bloques de construcción quirales.
- Las aminas primarias derivadas del alcaloide de la cinchona son catalizadores efectivos para esta transformación.
- Comprender el origen de la selectividad es esencial para la optimización del catalizador.
Objetivo del estudio:
- Para aclarar el origen de la enantioselectividad en la α-fluorización de cetonas cíclicas.
- Investigar el papel de la estructura del catalizador y la geometría de los estados de transición.
Principales métodos:
- Se emplearon cálculos funcionales de densidad para modelar el mecanismo de reacción.
- Se analizaron las estructuras de estado de transición para comprender los resultados estereocímicos.
Principales resultados:
- La preferencia de la silla del anillo de siete miembros en el estado de transición dicta la selectividad.
- Esta preferencia conformacional rige la selectividad facial de la transferencia de flúor.
Conclusiones:
- La dinámica conformacional de la cetona cíclica en el estado de transición es crítica para la enantioselectividad.
- La teoría funcional de la densidad proporciona valiosos conocimientos sobre el control estereoquímico de esta reacción.
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