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A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
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Oxidación de anilinas no activadas para generar nitrógeno arilico
Tianning Deng1, Wrickban Mazumdar1, Russell L Ford1
1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061, United States.
Journal of the American Chemical Society
|February 12, 2020
Resumen
Un nuevo método oxida anilinas 2-sustituidas a bajas temperaturas para crear N-arilo nitrenoides intermedios. Esto permite la síntesis de N-heterociclos funcionalizados, incluidos los 3H-indoles espirocíclicos y las benzazepinonas.
Área de la Ciencia:
- Química orgánica
- Química sintética
- Química Heterocíclica
Sus antecedentes:
- El desarrollo de rutas sintéticas eficientes para los heterociclos N es crucial en la química medicinal y la ciencia de los materiales.
- Los métodos tradicionales a menudo requieren condiciones duras o grupos de protección, lo que limita el alcance y la eficiencia del sustrato.
Objetivo del estudio:
- Desarrollar un nuevo método de oxidación a baja temperatura y sin grupos protectores para las anilinas 2-sustituidas.
- Para utilizar el intermediario de nitrenoide N-arilo generado para la construcción de heterociclos N funcionalizados.
Principales métodos:
- Oxidación de 2-anilinas sustituidas mediante el uso de feniliodino (III) bis (trifluoroacetato) (PIFA) con ácido trifluoroacético o triflato de escandio (Sc (OTf) 3).
- Utilizando el nitrenoide de N-arilo generado in situ para la formación de enlaces C-NAr y C-C.
Principales resultados:
- Síntesis exitosa de 3H-indoles espirocíclicos y bicíclicos y benzazepinonas.
- Demostración de las vías selectivas de formación de enlaces C-NAr y C-C.
- Identificación de los factores que controlan la selectividad en los procesos oxidativos.
Conclusiones:
- El método desarrollado proporciona una ruta fácil y eficiente a diversos heterociclos N en condiciones suaves.
- El intermediario N-arilo nitrenoide exhibe una reactividad versátil para la construcción de arquitecturas moleculares complejas.
- Este enfoque amplía la caja de herramientas sintéticas para acceder a valiosos 3H-indoles y benzazepinonas.
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