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Sustitución catalítica asimétrica vinílica y bisvinílica por propargilo

Hao-Dong Qian¹, Zhi-Heng Li¹, Shuang Deng²

¹CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P.R. China.

Journal of the American Chemical Society

|August 17, 2022

Resumen

Un nuevo ligando quiral N,N,P permite un control preciso de las reacciones catalizadas por cobre, produciendo compuestos carbonílicos no saturados alquínicos altamente enriquecidos con una amplia tolerancia de grupo funcional.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Las reacciones catalizadas por el cobre son cruciales en la síntesis orgánica.
El logro de una elevada regioselectividad y enantioselectividad en la sustitución de propargilo sigue siendo un reto.
El desarrollo de nuevos ligandos quirales es clave para avanzar en la catálisis asimétrica.

Objetivo del estudio:

Desarrollar un nuevo ligando quiral para la sustitución propargílica viníloga y bisviníloga catalizada por cobre.
Para lograr una distinta regionalidad y enantioselectividad en estas transformaciones.
Para sintetizar compuestos carbonílicos insaturados alquinílicos altamente enriquecidos con enantio.

Principales métodos:

Utilizó un nuevo ligando quiral N,N,P en reacciones catalizadas por cobre.
Se han investigado las reacciones de sustitución propargílica viníloga y bisviníloga.
Empleado una amplia gama de sustratos y grupos funcionales.

Principales resultados:

Se ha logrado un control distinto de la regionalidad y la enantiselectividad.
Desarrolló un método eficiente y selectivo para sintetizar compuestos objetivo.
Se ha demostrado una excelente tolerancia al grupo funcional y un amplio alcance en el sustrato.
Realizó con éxito la síntesis a escala de gramos y aplicó el método a transformaciones desafiantes.

Conclusiones:

El nuevo ligando quiral N,N,P es eficaz para controlar la selectividad en la sustitución propargílica catalizada por cobre.
El método desarrollado ofrece una vía eficiente para obtener valiosos compuestos de carbonilo no saturados alquinilados enriquecidos con enantio.
La utilidad sintética se valida a través de la ampliación y la aplicación a la síntesis de moléculas complejas.

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