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Arilación directa de los enlaces alifáticos C-H fuertes
Ian B Perry1, Thomas F Brewer1, Patrick J Sarver1
1Merck Center for Catalysis at Princeton University, Princeton, NJ, USA.
Nature
|August 3, 2018
Resumen
Este estudio introduce un nuevo método dual catalítico para la arilación directa de C ((sp3). Acopla eficientemente abundantes enlaces alifáticos C-H con bromuros de arilo, creando valiosos enlaces C-sp3 bajo condiciones suaves.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- La catálisis de metales de transición tiene limitaciones en la funcionalización de átomos de carbono híbridos sp3.
- La funcionalización directa del enlace C-H es ideal, pero es un desafío para los enlaces C ((sp3) -H fuertes y neutros.
- Los métodos existentes a menudo requieren sustratos prefuncionalizados o condiciones duras.
Objetivo del estudio:
- Desarrollar un protocolo suave y general para la arilación directa C ((sp3) de los enlaces alifáticos C-H.
- Para permitir la formación de enlaces C(sp3) -C(sp2) utilizando materiales de partida fácilmente disponibles.
- Para proporcionar una nueva ruta sintética a moléculas complejas y médicamente relevantes.
Principales métodos:
- Un sistema dual catalítico que combina la transferencia de átomos de hidrógeno impulsada por la luz (HAT) con la catálisis del níquel.
- El fotocatalizador de polioxometalato facilita el HAT de enlaces C-H fuertes y neutros para generar radicales centrados en el carbono.
- El catalizador de níquel media el acoplamiento cruzado de estos radicales con bromuros de arilo.
Principales resultados:
- El éxito de la correlación directa C ((sp3) de diversos marcos alifáticos.
- Formación de productos de acoplamiento cruzado C ((sp3) - C ((sp2) en condiciones suaves.
- Aplicabilidad demostrada para productos naturales y materias primas químicas.
Conclusiones:
- El protocolo desarrollado ofrece un acceso sin precedentes a moléculas complejas en un solo paso.
- Este método supera las limitaciones de las reacciones de acoplamiento cruzado tradicionales en carbones híbridos sp3.
- La tecnología permite la funcionalización en sitios previamente no reactivos, expandiendo las posibilidades sintéticas.
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