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Selectividad posicional en funcionalizaciones C-H de 2-benzilfuranos con catalizadores bimetales

Jiadi Zhang¹, Sheng-Chun Sha¹, Ana Bellomo¹

¹Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania , 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States.

Journal of the American Chemical Society

|March 4, 2016

Resumen

Los investigadores desarrollaron nuevos catalizadores bimetálicos para la formación selectiva de enlaces carbono-carbono en la síntesis farmacéutica. Estos catalizadores controlan la selectividad del sitio en los 2-benzilfuranos, lo que permite la arilación de los enlaces C-H sp2 y sp3.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

Las reacciones de formación de enlaces carbono-carbono catalizadas por metales son cruciales para la síntesis de agentes farmacéuticos.
El control de la selectividad entre los enlaces de C-H no equivalentes en la funcionalización de C-H catalizada por metales de transición sigue siendo un desafío significativo.

Objetivo del estudio:

Desarrollar un método para dirigir la selectividad del sitio en la arilación de 2-benzilfuranos.
Investigar el papel de los catalizadores bimetálicos en el logro de la selectividad del sitio divergente.

Principales métodos:

Se utilizaron catalizadores bimetálicos para lograr la arilación selectiva del sitio de los 2-benzilfuranos.
Exploró la modulación de la cooperatividad del catalizador para controlar la selectividad.
Se ha investigado la influencia de las bases y de los aditivos (por ejemplo, K o Li·12-corona-4) en los resultados de la reacción.

Principales resultados:

Se logró un alto control de la selectividad del sitio en la arilación de 2-benzilfuranos.
Se ha demostrado la arilación divergente de los enlaces C-H sp2 y sp3.
Interacciones cation-π identificadas como un factor clave que rige la selectividad, ajustable por base y aditivos.

Conclusiones:

Los catalizadores bimetálicos ofrecen una poderosa estrategia para controlar la selectividad del sitio en la funcionalización C-H.
La modulación de la cooperatividad del catalizador y las interacciones catión-π permite la arilación selectiva de diversos enlaces C-H.
Este enfoque hace avanzar la síntesis de productos farmacéuticos intermedios complejos.

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