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Síntesis catalítica enantioselectiva de bromuros de alquilo difluorados

Mark D Levin¹, John M Ovian¹, Jacquelyne A Read^1,2

¹Department of Chemistry & Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.

Journal of the American Chemical Society

|August 18, 2020

Resumen

Este estudio introduce una síntesis enantioselectiva de bloques de construcción de difluoroalquilo bromuro utilizando catalizadores de iodoareno. Los catalizadores optimizados y las condiciones de reacción producen productos altamente enantioselectivos para aplicaciones versátiles.

Área de la Ciencia:

Química orgánica
Química del fluor
Catálisis

Sus antecedentes:

El reto de la síntesis de compuestos fluorados enantioméricamente enriquecidos.
Necesidad de bloques de construcción versátiles en química medicinal y ciencia de los materiales.
Limitaciones de los métodos existentes para la difluoroalquilación.

Objetivo del estudio:

Desarrollar una síntesis enantioselectiva de los bloques de construcción del β,β-difluoroalquilo bromuro.
Identificar y mitigar las vías de descomposición del catalizador.
Investigar los orígenes de la enantioselectividad.

Principales métodos:

Reorganización oxidativa catalizada por el iodoareno de los α-bromostirenos.
Utilizó fluoruro de hidrógeno-piridina como fuente de fluoruro.
Se utiliza el ácido metacloroperoxibenzoico (m-CPBA) como oxidante.

Principales resultados:

Se ha logrado una alta enantioselectividad en la síntesis de difluoroalquilbromuros.
Desarrolló un catalizador mejorado con cargas más bajas al abordar las vías de descomposición.
Demostró la versatilidad de los productos a través de reacciones de sustitución enantiospecíficas.

Conclusiones:

Se ha establecido un método robusto para la síntesis enantioselectiva de bloques de construcción valiosos de difluoroalquilbromuro.
Los estudios computacionales proporcionaron información sobre las principales interacciones CH-π y π-π que rigen la enantioselectividad.
La metodología desarrollada ofrece una vía prometedora para acceder a moléculas fluoradas complejas.

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