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Arilación Meta-C-H Promovida por Ligandos de las Anilinas, Fenoles y Heterociclos

Peng Wang¹, Marcus E Farmer¹, Xing Huo¹

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

Journal of the American Chemical Society

|July 8, 2016

Resumen

Una nueva clase de ligandos 3-acetilamino-2-hidroxipiridina permite reacciones de arilación meta-C-H versátiles. Este método amplía el alcance del sustrato y ofrece nuevas posibilidades para el descubrimiento de fármacos, incluidos los primeros pasos hacia protocolos sintéticos más ecológicos.

Área de la Ciencia:

Química orgánica
Metodología sintética
Catálisis

Sus antecedentes:

La activación y la funcionalidad de C-H son cruciales en la síntesis orgánica moderna.
La meta-C-H arilación ofrece una ruta directa a los compuestos aromáticos complejos.
El desarrollo de ligandos eficientes y versátiles es clave para avanzar en la funcionalidad C-H.

Objetivo del estudio:

Desarrollar una nueva clase de ligandos para promover la arilación meta-CH.
Ampliar el ámbito de aplicación de la meta-C-H a diversos sustratos y socios de acoplamiento.
Demostrar la utilidad de esta metodología en el descubrimiento de fármacos y explorar condiciones de reacción más ecológicas.

Principales métodos:

Síntesis y aplicación de los ligandos de la 3-acetilamino-2-hidroxipiridina.
Utilizando el norborneno como mediador transitorio para la arilación meta-C-H.
Evaluación de las condiciones de reacción para optimizar el rendimiento y la selectividad.
Prueba de la metodología con varias anilinas, aminas heterocíclicas, fenoles y heterociclos.

Principales resultados:

Se desarrolló un andamio versátil de ligando de 3-acetilamino-2-hidroxipiridina.
Se demostraron más de 120 ejemplos de arilación meta-C-H con un amplio alcance de sustrato.
Se logró por primera vez la arilación meta-C-H utilizando ioduros de arilo heterocíclicos.
El método se aplicó con éxito a un derivado de la lenalidomida, mostrando el potencial de descubrimiento de fármacos.
Se logró un progreso inicial hacia un protocolo libre de plata.

Conclusiones:

Los ligandos desarrollados proporcionan una herramienta poderosa para la arilación meta-CH.
Esta metodología amplía significativamente la accesibilidad sintética de los compuestos meta-arilados.
El enfoque es prometedor para el descubrimiento y desarrollo de fármacos eficientes.
El trabajo futuro puede centrarse en optimizar aún más la reacción para la sostenibilidad.

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