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La formación de enlaces C-C catalizados por hierro en la posición alfa de las aminas alifáticas a través de la
Naohiko Yoshikai1, Adam Mieczkowski, Arimasa Matsumoto
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033.
Journal of the American Chemical Society
|April 6, 2010
Resumen
La catálisis del hierro permite la funcionalización de C-H a través de intermediarios similares a los radicales. Este estudio detalla una nueva reacción mediada por organohierro para una arilación, alquenilación y alquilación eficientes de los enlaces C-H sp.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Síntesis orgánica La síntesis orgánica.
- La catálisis de la catálisis.
Sus antecedentes:
- La formación de enlaces carbono-carbono es fundamental en la síntesis orgánica.
- Las especies de hierro orgánico pueden mediar reacciones con características similares a las de los radicales.
- La funcionalización directa de los bonos C-H sigue siendo un desafío sintético.
Objetivo del estudio:
- Desarrollar un nuevo método catalizado por hierro para la funcionalización C-H.
- Para explorar el alcance de la arilación, alquenilación y alquilación mediadas por el hierro orgánico.
- Para aclarar el mecanismo que implica la translocación radical.
Principales métodos:
- Reacción de la N-(2-iodofenilmetil) dialquilamina con los reactivos Grignard o diorganozinc.
- Se utilizan cantidades catalíticas de hierro (III) acetilacetonato (Fe (acac) (3)).
- Investigaciones mecánicas que incluyen experimentos de etiquetado isotópico.
Principales resultados:
- Se obtienen buenos a excelentes rendimientos de productos de arylación, alquenilación o alquilación.
- Funcionalización demostrada del enlace sp(3) C-H adyacente al grupo amino.
- La evidencia sugiere un mecanismo que involucra la translocación radical iniciada por la eliminación de yoduro.
Conclusiones:
- Desarrolló una estrategia eficiente de funcionalización C-H catalizada por hierro.
- La metodología permite diversas formaciones de enlace C-C.
- La reacción procede a través de una vía de translocación radical mediada por especies de organohierro.
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