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A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
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Alquilación versátil de (hetero) ioduros arílicos con cetonas a través de la activación β-C
Ru-Yi Zhu1, Luo-Yan Liu1, Han Seul Park1
1Department of Chemistry, The Scripps Research Institute , La Jolla, California 92037, United States.
Journal of the American Chemical Society
|November 1, 2017
Resumen
Este estudio introduce un nuevo método catalizado por el paladio para la arilación C-H de las cetonas. El enfoque desarrollado ofrece una ruta versátil para el acoplamiento alquilo-heteroarilo, superando las limitaciones anteriores en la funcionalización de cetonas.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- La funcionalización directa de C-H es una herramienta poderosa en la síntesis orgánica.
- Los métodos anteriores para la arilación β-C ((sp3) -H de cetonas se enfrentaron a limitaciones en el alcance y la gestión auxiliar.
- Las cetonas son bloques de construcción sintéticos omnipresentes y valiosos.
Objetivo del estudio:
- Desarrollar un nuevo y eficiente método catalizado por el paladio para la arilación β-C ((sp3) -H de cetonas.
- Utilizar un auxiliar fácilmente disponible para una fácil instalación y extracción.
- Ampliar el alcance de las reacciones de acoplamiento de cetonas y (hetero) arilos.
Principales métodos:
- Reacción catalizada por paladio (II) que emplea un auxiliar de ácido aminooxiacético 2,2-dimetilo.
- La activación β-C(sp3)-H y la posterior arilación de varios sustratos cetónicos.
- Acoplamiento con una amplia gama de yoduros de (hetero) arilo.
Principales resultados:
- Se logró una exitosa β-C(sp3)-H (hetero) airación de diversas cetonas.
- El auxiliar demostró ser fácil de instalar y quitar, lo que mejora la practicidad.
- El método mostró un amplio alcance tanto para la cetona como para los socios de acoplamiento de (hetero) arilo yoduro.
Conclusiones:
- El método desarrollado proporciona un avance significativo con respecto a las estrategias anteriores de arilación β-C ((sp3) -H para las cetonas.
- Este enfoque ofrece una vía ampliamente aplicable y eficiente para el acoplamiento de alquilo-hetero-arilo, incluidos los alquilos primarios y secundarios.
- La disponibilidad inmediata de cetonas y el auxiliar hacen de esta una herramienta sintética valiosa.
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