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Palladio ((II) - Sin-hidroarilación regioselectiva catalizada de alcinos disueltos utilizando un grupo directivo

Zhen Liu¹, Joseph Derosa¹, Keary M Engle¹

¹Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.

Journal of the American Chemical Society

|September 8, 2016

Resumen

Una nueva reacción catalizada por el paladio permite la sin-hidroariación regioselectiva de las aminas homopropargilo. Este método crea eficientemente valiosos motivos de aminas homoalílicas 4,4-disubstituidas que se encuentran en muchas moléculas de fármacos.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

Las aminas homoalílicas son motivos estructurales cruciales en productos farmacéuticos y compuestos bioactivos.
La síntesis regioselectiva de moléculas orgánicas complejas sigue siendo un desafío significativo en la química orgánica.

Objetivo del estudio:

Desarrollar una nueva reacción de sin-hidroarilación regioselectiva catalizada por el paladio para las aminas homopropargilo.
Para controlar la selectividad de la reacción mediante el uso de un grupo direccionable de bidentato.

Principales métodos:

Para la reacción de hidroarilación se empleó la catálisis con palladio.
Para controlar la regioselectividad se utilizó un grupo direccionable de bidentato.
Se realizó una optimización de las condiciones de reacción para varios sustratos alquinos.

Principales resultados:

El método desarrollado logró una alta regioselectividad en la sin-hidroarilación de las aminas homopropargilo.
Tanto los sustratos de dialquilo como los de alquilo-alquino fueron hidro- arilados con éxito.
La reacción produjo productos que contienen el motivo de amina homoalílica 4,4-disubstituido.

Conclusiones:

Se ha establecido una nueva y eficiente vía catalizada por el paladio para las aminas homoalílicas 4,4-disubstituidas.
El uso de un grupo de dirección proporciona un excelente control de la selectividad de la reacción.
Esta metodología ofrece una herramienta valiosa para la síntesis de fármacos candidatos y compuestos bioactivos.

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