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Funcionalización C-H divergente controlada por ligandos de aldehídos con Enynes por catalizadores de cobalto
Rajagopal Santhoshkumar1, Subramaniyan Mannathan1, Chien-Hong Cheng1
1Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
Journal of the American Chemical Society
|December 10, 2015
Resumen
Una nueva reacción catalizada por cobalto sintetiza eficientemente pirrolidinas y dihidrofuranos funcionalizados a partir de 1,6-eninas y aldehídos. Este método atómico económico ofrece una alta quimioselectividad y estereoselectividad para compuestos heterocíclicos valiosos.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- Las pirrolidinas y los dihidrofuranos son bastidores heterocíclicos cruciales en los productos farmacéuticos y naturales.
- Las rutas sintéticas eficientes y selectivas para estos compuestos son muy buscadas en la química orgánica.
- La catálisis del cobalto ofrece una vía prometedora para desarrollar nuevas estrategias de ciclización.
Objetivo del estudio:
- Desarrollar un método altamente económico de paso y átomo para sintetizar pirrolidinas y dihidrofuranos funcionalizados.
- Para explorar la utilidad de la catálisis de cobalto en la ciclización de 1,6-eninas con aldehídos.
- Para lograr una alta quimioselectividad y estereoselectividad en la formación de estos productos heterocíclicos.
Principales métodos:
- Reacción de ciclización catalizada por cobalto utilizando 1,6-eninas y aldehídos como sustratos.
- Investigación de los mecanismos de reacción en los que intervienen los intermediarios del cobaltaciclo.
- Selección de ligandos para controlar la funcionalidad y la selectividad C-H conmutables.
Principales resultados:
- Síntesis exitosa de pirrolidinas y dihidrofuranos funcionalizados con altos rendimientos.
- Demostración de una alta quimioselectividad y estereoselectividad en el proceso de ciclización.
- Elucidación de un ciclo catalítico plausible que involucra la formación de cobaltaciclos y la funcionalización de C-H.
Conclusiones:
- La ciclización catalizada por cobalto desarrollada es un método poderoso y eficiente para acceder a diversas pirrolidinas y dihidrofuranos funcionalizados.
- La selectividad de la reacción se puede ajustar modificando las propiedades electrónicas del ligando.
- Esta metodología proporciona una herramienta valiosa para los químicos sintéticos en la construcción de moléculas heterocíclicas complejas.
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