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Síntesis de aminas primarias estéricamente inhibidas por catálisis fotorredóxica simultánea

Michael C Nicastri¹, Dan Lehnherr², Yu-Hong Lam³

¹Department of Chemistry , Columbia University , New York , New York 10027 , United States.

Journal of the American Chemical Society

|January 7, 2020

Resumen

Este estudio introduce un nuevo método de catálisis fotorredóxica para la síntesis de aminas primarias obstruidas a partir de oximas de O-benzoilo y cianoarenos. Este enfoque crea de manera eficiente estructuras de aminas complejas, incluidas las con grupos alfa-trifluorometilo.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

Las aminas primarias son bloques de construcción cruciales en el diseño de productos farmacéuticos y ligandos.
La síntesis directa de aminas primarias con carbohidratos alfa completamente sustituidos sigue siendo un desafío.
Los métodos existentes para la síntesis de aminas son limitados para los objetivos estérilmente obstaculizados.

Objetivo del estudio:

Desarrollar una nueva vía sintética para aminas primarias con centros alfa-carbono completamente sustituidos.
Para permitir la síntesis de aminas estéricamente impedidas, incluidas las con grupos alfa-trifluorometilo.
Para aclarar el mecanismo catalítico de esta transformación.

Principales métodos:

Catalización por fotorreducción utilizando oximas de O-benzoilo y cianoarenos.
Catálisis simultánea en tándem que incluye ciclos de sensibilización por tripletes y ciclos reductivos.
Heteroacoplamiento radical de precursores de oxima fácilmente disponibles.

Principales resultados:

Síntesis exitosa de aminas primarias con carbohidratos alfa completamente sustituidos.
Se ha demostrado la síntesis de alfa-trifluorometilaminas.
Propuso un mecanismo que implicaba una catálisis simultánea en tándem por el fotocatalizador.

Conclusiones:

El método fotorredóxico desarrollado proporciona un acceso eficiente a las aminas primarias obstaculizadas.
Esta metodología amplía la caja de herramientas sintéticas para crear estructuras de aminas complejas.
La comprensión del mecanismo catalítico ayuda a una mayor optimización y aplicación.

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