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Estrategia de caminar en cadena para la síntesis orgánica: cicloisomerización catalítica de 1,n-dienes

Takuya Kochi¹, Taro Hamasaki, Yuka Aoyama

¹Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan. kochi@chem.keio.ac.jp

Journal of the American Chemical Society

|September 25, 2012

Resumen

Este estudio introduce la catálisis en cadena para la creación de enlaces carbono-carbono en la síntesis orgánica. Este nuevo método permite la funcionalización de enlaces C-H no reactivos, ofreciendo nuevas posibilidades sintéticas.

Área de la Ciencia:

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

Sus antecedentes:

La formación de enlaces carbono-carbono es fundamental en la síntesis orgánica.
Los métodos existentes a menudo luchan con la funcionalización de enlaces C-H no reactivos.
El caminar catalítico en cadena ofrece un nuevo paradigma para la funcionalidad C-H.

Objetivo del estudio:

Describir la construcción catalítica de los enlaces carbono-carbono utilizando la marcha en cadena en pequeñas moléculas orgánicas.
Para demostrar la utilidad de la cicloisomerización catalizada por el paladio de 1,n-dienes a través de la marcha en cadena.
Desarrollar un protocolo para la síntesis selectiva de derivados biciclo[4.3.0]nonano.

Principales métodos:

Utilizó un catalizador de paladio-1,10-fenantrolina para las reacciones de caminar en cadena.
Se empleó un protocolo de cicloisomerización/hidrogenación para la conversión de dieno.
Investigó la regioselectividad de la migración del catalizador en 1,n-dienes.

Principales resultados:

Se logró la cicloisomerización catalítica de 1,n-dienes para formar productos de anillo de cinco miembros.
Se han sintetizado con éxito derivados biciclo[4.3.0]nonano de 1,7- a 1,14-dienes.
Se demostró que el caminar en cadena permite a los catalizadores encontrar sitios óptimos de formación de enlaces.

Conclusiones:

El caminar en cadena proporciona una nueva estrategia para la síntesis orgánica.
Esta metodología permite la funcionalización de bonos C-H previamente no reactivos.
El protocolo desarrollado ofrece acceso selectivo a estructuras cíclicas complejas.

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