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La expansión del anillo catalizado de azidas de arilo sustituidos por ciclobutanol para acceder a heterociclos N de

Wrickban Mazumdar¹, Navendu Jana¹, Bryant T Thurman¹

¹Department of Chemistry, University of Illinois at Chicago , 845 West Taylor Street, Chicago, Illinois 60607-7061, United States.

Journal of the American Chemical Society

|March 30, 2017

Resumen

Los investigadores descubrieron una nueva reacción catalizada por el rodio para sintetizar heterociclos de nitrógeno de tamaño mediano. Este método utiliza azidas de arilo sustituidos por ortociclobutanol y presenta un paso de expansión de anillo altamente selectivo.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los heterociclos de nitrógeno son andamios cruciales en la química medicinal y la ciencia de los materiales.
La síntesis eficiente de heterociclos de tamaño medio sigue siendo un desafío importante en la síntesis orgánica.
Las reacciones catalizadas por rodio ofrecen potentes herramientas para la formación de enlaces C-N y la síntesis heterocíclica.

Objetivo del estudio:

Para descubrir un nuevo patrón de reactividad para el rodio ((II) -N-arylnitrenes.
Desarrollar una nueva vía sintética para los heterociclos de nitrógeno de tamaño medio.
Para aclarar el mecanismo del paso de expansión del anillo de la llave.

Principales métodos:

Utilizando azidas de arilo sustituidas por ortociclobutanol como materias primas.
Utilizando un catalizador de rodio para generar productos intermedios de N-arilnitreno.
Investigando las vías de reacción a través de experimentos mecanicistas.

Principales resultados:

Se identificó un nuevo patrón de reactividad para los Rh (II) -N- arilnitrenos.
Se logró una síntesis catalítica de heterociclos N de tamaño medio.
Se demostró que el paso clave de expansión del anillo es quimioselectivo y estereospecífico.
Los estudios mecanicistas revelaron una aminación competitiva del enlace sp3 C-H.

Conclusiones:

La reactividad descubierta permite una síntesis eficiente de heterociclos N de tamaño medio.
El ciclo catalítico incluye un intermediario de N-arilnitreno de rodio.
La comprensión de las vías de competencia como la aminación C-H es clave para optimizar la reacción.

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