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La catálisis de tungsteno de baja valencia permite la isomerización selectiva del sitio y la hidroboración de
Tanner C Jankins1, Raul Martin-Montero2, Phillippa Cooper1
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 9, 2021
Resumen
La catálisis de tungsteno permite la hidroboración de alquenos no activados en enlaces C-H distales utilizando grupos de dirección. Este método simple y selectivo ofrece un nuevo patrón de selectividad de sitio para las reacciones de berilización.
Área de la Ciencia:
- Química organometálica
- Catálisis
- Síntesis orgánica
Sus antecedentes:
- La hidroboración es una transformación clave en la síntesis orgánica.
- Las estrategias de grupo dirigidas son cruciales para la funcionalización de C-H selectiva del sitio.
- Los métodos catalíticos para la funcionalización de enlaces C-H no activados siguen siendo un desafío.
Objetivo del estudio:
- Desarrollar una nueva hidroboración catalizada por tungsteno de alquenos no activados.
- Para lograr la funcionalización selectiva en los enlaces C ((sp3) -H distales.
- Explorar la utilidad de los grupos de dirección nativos en esta transformación.
Principales métodos:
- Reacción de hidroboración catalizada por el tungsteno.
- Se utilizaron alquenos no activados con grupos de dirección nativos.
- Condiciones de reacción investigadas para obtener un rendimiento y una selectividad óptimos.
Principales resultados:
- Se obtiene la hidroboración de alquenos no activados en enlaces C ((sp3) -H distales.
- Se ha demostrado una alta regionalidad y quimioselectividad.
- Mostró un amplio alcance de sustrato para el método desarrollado.
Conclusiones:
- El método desarrollado catalizado por tungsteno proporciona una ruta simple y selectiva a los alquenos hidroborados.
- Este enfoque ofrece un patrón de selectividad de sitio complementario en comparación con las reacciones de berilización existentes.
- La metodología amplía el conjunto de herramientas para la funcionalización de C-H y la difuncionalización de alceno.
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