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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

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Alilación catalitica asimétrica de las iminas

Jie Liu¹, Chao-Guo Cao¹, Hong-Bao Sun¹

¹Department of Emergency, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy , Chengdu 610041, China.

Journal of the American Chemical Society

|September 20, 2016

Resumen

Este estudio introduce un método catalizado por iridio para crear valiosas aminas homoalílicas 1,4-disubstituidas a partir de iminas. La nueva alilación asimétrica umpolung ofrece una ruta directa a estos compuestos importantes.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Las aminas homoalílicas son bloques de construcción cruciales en la síntesis orgánica.
Los métodos existentes para sintetizar aminas homoalílicas 1,4-disubstituidas son a menudo limitados o complejos.

Objetivo del estudio:

Desarrollar un enfoque catalítico general y eficiente para la síntesis asimétrica de aminas homoalílicas 1,4-disubstituidas.
Establecer una alilación de iminas catalizada por iridio como una estrategia sintética viable.

Principales métodos:

Alilación asimétrica umpolungada catalizada por iridio de las iminas.
Reacción en cascada que implica la alilación regioselectiva intermolecular de los aniones 2-azaalilo.
Posterior reorganización de 2-aza-Cope.

Principales resultados:

Síntesis exitosa de aminas primarias homoalílicas 1,4-disubstituidas enriquecidas con enantio.
Se ha demostrado un amplio alcance y tolerancia del sustrato.
Se utilizan reactivos y catalizadores fácilmente disponibles.

Conclusiones:

El método descrito proporciona un acceso sencillo y general a aminas homoalílicas 1,4-disubstituidas.
Esta alilación asimétrica catalítica de umpolung representa un avance significativo en la síntesis de aminas.

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