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Reacción de tipo Heck de haluros de alquilo con estirenos catalizados por cobalto

Yousuke Ikeda¹, Tomoaki Nakamura, Hideki Yorimitsu

¹Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.

Journal of the American Chemical Society

|June 6, 2002

Resumen

Un complejo de cobalto cataliza la alquilación del estireno utilizando haluros de alquilo para producir beta-alquilostirenos. Es probable que la reacción proceda a través de un mecanismo radical, ofreciendo una nueva ruta sintética.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Síntesis orgánica La síntesis orgánica.

Sus antecedentes:

Las reacciones de alquilación son fundamentales en la síntesis orgánica.
El desarrollo de sistemas catalíticos eficientes para la formación de enlaces C-C es crucial.

Objetivo del estudio:

Para investigar la actividad catalítica de un complejo de cobalto en la alquilación del estireno.
Para explorar el alcance de los haluros de alquilo utilizables en esta reacción.
Para dilucidar el mecanismo de reacción.

Principales métodos:

Reacción catalítica mediante el uso del complejo de cobalto (CoCl2[1,6-bis(difenilfosfino) hexano]).
Reactivos: estirenos y Me3SiCH2MgCl en éter.
Utilizó varios haluros de alquilo como fuentes de alquilo.

Principales resultados:

Se logró la formación de beta-alquilistirenos.
La reacción demostró tolerancia a una gama de haluros de alquilo, incluidos los cloruros de alquilo.
La evidencia experimental sugiere fuertemente un mecanismo radical.

Conclusiones:

El complejo de cobalto es un catalizador eficaz para la beta-alquilación del estireno.
Este método proporciona una ruta versátil para los beta-alquilistirenos.
El mecanismo radical propuesto ofrece información sobre la formación de enlaces catalíticos C-C.

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