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Regiodivergente Radical-Relay Alqueno Dicarbofuncionalización
Zhong Liu1, Francesco D'Amico1,2, Ruben Martin1,3
1The Barcelona Institute of Science and Technology, Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain.
Journal of the American Chemical Society
|October 10, 2024
Resumen
Este estudio introduce un nuevo método catalizado por níquel para la difuncionalización regioselectiva de las olefinas, creando enlaces cruciales carbono-carbono a través de un mecanismo de relevo radical.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- Las olefinas no activadas son sustratos difíciles para la funcionalización selectiva.
- El desarrollo de métodos para la formación de enlaces C-C de largo alcance es esencial en la síntesis orgánica.
Objetivo del estudio:
- Para reportar una 1,n-dicarbofuncionalización regiodivergente de las olefinas no activadas.
- Para permitir la formación de ambos enlaces C(sp3) -C(sp3) y C(sp2) -C(sp3).
- Para lograr esta transformación se utiliza la catálisis de níquel y un relé radical.
Principales métodos:
- Reacción catalizada por níquel empleando un mecanismo de relevo de radicales.
- Utilizando olefinas no activadas como sustratos.
- Investigar el papel de la columna vertebral del ligando en la determinación de la selectividad del sitio.
Principales resultados:
- El éxito de la 1,n-dicarbofuncionalización regioselectiva de las olefinas no activadas.
- Formación de enlaces C(sp3) -C(sp3) y C(sp2) -C(sp3, incluidos los enlaces de largo alcance.
- Pruebas que apoyan un mecanismo entrelazado de adición de radicales de transferencia atómica (ATRA) y caminata en cadena.
Conclusiones:
- Se ha desarrollado un versátil sistema de relevo de radicales catalizados por Ni para la difuncionalización de olefinas.
- El método permite la formación controlada de diversos enlaces C-C.
- El diseño de ligandos es crítico para controlar la selectividad del sitio en este proceso de relevo radical.
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