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Activación de enlaces aliloides formales C-H de alquenos provocados por una amida de sodio
Wei Bao1, Hanno Kossen1, Uwe Schneider1
1EaStCHEM School of Chemistry, The University of Edinburgh , The King's Buildings, David Brewster Road, Edinburgh EH9 3FJ, U.K.
Journal of the American Chemical Society
|March 16, 2017
Resumen
La amida de sodio cataliza eficientemente la activación del enlace alilico C ((sp3) -H en los alquenos. Este método sin metales de transición permite la síntesis de alto rendimiento de aminas complejas a través de la formación de enlaces C-C con iminas.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- La activación del enlace alilico C ((sp3) -H es crucial para la síntesis orgánica.
- El desarrollo de sistemas catalíticos libres de metales de transición sigue siendo un desafío importante.
- La formación selectiva de enlaces C-C es clave para la construcción de arquitecturas moleculares complejas.
Objetivo del estudio:
- Para explorar el potencial catalítico de la amida de sodio para la activación del enlace alilico C ((sp3) -H.
- Desarrollar un nuevo método sin metales de transición para la formación de enlaces C-C.
- Para sintetizar aminas complejas con alta selectividad y rendimiento.
Principales métodos:
- Se utiliza la amida de sodio como catalizador para la activación formal del enlace alilico C ((sp3) -H de los alquenos.
- Investigó las reacciones posteriores de formación de enlaces C-C con varias iminas.
- Se utilizaron condiciones de reacción suaves y se analizó la selectividad del producto.
- Intermedios de reacción caracterizados mediante resonancia magnética nuclear y espectrometría de masas de alta resolución.
Principales resultados:
- Se ha logrado una activación eficiente del enlace alilico C ((sp3) -H en condiciones suaves.
- Se ha demostrado un alto rendimiento, una regioselectividad completa y una excelente selectividad geométrica en formaciones de enlaces C-C.
- Muestra tolerancia hacia las funcionalidades aromáticas de ciano, cloro y bromo.
- Se han sintetizado con éxito aminas complejas con enlaces dobles CC y unidades heteroaromáticas en un solo paso.
- Se han identificado dos productos intermedios a base de sodio con actividad catalítica.
Conclusiones:
- La amida de sodio es un catalizador muy eficaz para la activación de C ((sp3)-H y el acoplamiento C-C posterior.
- Este enfoque de transición sin metales ofrece una vía sostenible y eficiente para aminas complejas.
- El estudio pone de relieve el papel único del sodio en la catálisis y proporciona información sobre los mecanismos de reacción.
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