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La aminocianuación intramolecular de alquenos por catálisis cooperativa de paladio y boro

Yosuke Miyazaki¹, Naoki Ohta, Kazuhiko Semba

¹Department of Material Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.

Journal of the American Chemical Society

|March 4, 2014

Resumen

Los investigadores desarrollaron un nuevo catalizador de paladio/triorganoboron para la aminocianatión intramolecular de alceno. Este método sintetiza de manera eficiente las indolinas y pirrolidinas sustituidas, ofreciendo una nueva ruta para la cianofuncionalización.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La aminocianuación intramolecular es una transformación sintética valiosa.
Los métodos eficientes para la construcción de heterociclos que contienen nitrógeno están en demanda.
La catálisis con paladio ofrece vías versátiles para la formación de enlaces C-N.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico cooperativo de paladio y triorganoboron.
Para lograr la aminocianatización intramolecular de alquenos a través de la escisión de enlaces N-CN.
Para sintetizar indolinas y pirrolidinas sustituidas con alta selectividad.

Principales métodos:

Utilizando un catalizador cooperativo de paladio y triorganoboron.
Utilizando el 4,5-Bis(difenilfosfino) -9,9-dimetilxanteno (Xantphos) como su ligando.
Investigando la escisión de los enlaces N-CN para la cianofuncionalización.

Principales resultados:

El sistema de catalizador desarrollado promueve efectivamente la aminocianatión intramolecular.
Se logró una alta quimioselectividad y regioselectividad utilizando el ligando Xantphos.
Se sintetizó una variedad de indolinas y pirrolidinas sustituidas.
Se demostró una aminocianatización enantioselectiva preliminar.

Conclusiones:

Se ha establecido un método novedoso y eficiente para la aminocianatión intramolecular de alquenos.
El catalizador cooperativo de paladio/triorganoboron, con ligando Xantphos, permite la síntesis selectiva de valiosos compuestos heterocíclicos.
Este trabajo proporciona una nueva herramienta para la cianofuncionalización y la síntesis heterocíclica.

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