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La α-cianatización de aminas mediada por iones de tropilio de las aminas
Julia M Allen1, Tristan H Lambert
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|January 6, 2011
Resumen
El ion tropilio permite la alfa-cianatización directa de aminas mediante la oxidación de sustratos a iones de iminio, que luego reaccionan con el cianuro. Este método eficiente produce aminonitriles con subproductos simples.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
Sus antecedentes:
- La alfa-cianatización de aminas es una transformación crucial en la síntesis orgánica.
- Los métodos existentes a menudo requieren condiciones duras o reactivos especializados.
Objetivo del estudio:
- Desarrollar un método nuevo y eficiente para la alfa-cianatización de aminas.
- Explorar la utilidad del ion trofilio como oxidante en la funcionalización de aminas.
Principales métodos:
- El ion tropilio se utilizó para mediar la alfa-cianatización directa de varios sustratos de aminas en presencia de cianuro de potasio (KCN).
- La reacción procede a través de la oxidación de aminas a iones de iminio, seguido de la metátesis de sales con cianuro.
- El método se demostró en trece sustratos diferentes, incluida una síntesis a escala de gramos.
Principales resultados:
- Síntesis exitosa de aminonitriles de diversos precursores de aminas.
- La reacción genera subproductos fácilmente extraíbles: cicloheptatrieno y tetrafluoroborato de potasio.
- También se demostró una reorganización oxidativa aza-Cope mediada por el ion trofilio.
Conclusiones:
- El ion tropilio proporciona un reactivo suave y eficaz para la alfa-cianización de aminas.
- Este método ofrece una valiosa adición al kit de herramientas del químico sintético para la construcción de compuestos aminonitrílicos.
- La eficiencia de la reacción y el procesamiento simple mejoran su aplicabilidad práctica.
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