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Ciclizaciones arilativas de los alquinolos catalizadas por el paladio y regionalizadas controladas

Daishi Fujino¹, Hideki Yorimitsu, Atsuhiro Osuka

¹Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan.

Journal of the American Chemical Society

|April 17, 2014

Resumen

Este estudio demuestra ciclizaciones catalíticas controlables de los alquinoles utilizando intermediarios de arilpaladio. Este método ofrece una síntesis divergente de heterociclos que contienen oxígeno y alquinas funcionalizadas.

Área de la Ciencia:

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

Sus antecedentes:

Los intermediarios de arylpalladium son cruciales en las reacciones de acoplamiento cruzado.
El control de la regioselectividad en la difuncionalización alquina sigue siendo un desafío.
Los heterociclos que contienen oxígeno son frecuentes en los productos farmacéuticos.

Objetivo del estudio:

Desarrollar un método para la difuncionalización regioselectiva y controlable de las alquinas.
Demostrar la síntesis de heterociclos que contienen oxígeno a través de ciclizaciones arilativas catalíticas.
Para mostrar la utilidad de este método en la síntesis de moléculas complejas.

Principales métodos:

Ajuste de la reactividad de los intermediarios de arilpaladio.
Ciclizaciones arilativas catalíticas 5-exo y 6-endo de los alquinoles.
Utilizando alcinoles como sustratos para la síntesis divergente.

Principales resultados:

Se lograron ciclizaciones catalíticas arilativas controlables de 5-exo y 6-endo de los alquinoles.
Demostrado difuncionalización regioselectiva de las alquinas.
Sintetizó varios heterociclos que contienen oxígeno.
Completó una síntesis formal de un antagonista del receptor hNK-1.

Conclusiones:

El método desarrollado permite una regioselectividad controlada en la difuncionalización de alquinos.
Este enfoque proporciona una ruta versátil a los heterociclos que contienen oxígeno.
La metodología es aplicable a la síntesis de compuestos biológicamente relevantes.

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