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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
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Participación de los alquenos en el metallafotoredox: un enfoque de clasificación triple catalítica y radical para el
Qinyan Cai1, Iona M McWhinnie1, Nathan W Dow1
1Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|April 24, 2024
Resumen
El presente estudio introduce un nuevo método de cocatálisis triple para el acoplamiento cruzado C(sp3) -C(sp3). Enlaza eficientemente alquenos y alcoholes, creando estructuras alifáticas complejas para la química medicinal.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Química medicinal
Sus antecedentes:
- El acoplamiento metallafotoredox es vital para la síntesis de andamios alifáticos similares a las drogas.
- La expansión de los socios de acoplamiento en las reacciones metalfotoredóxicas puede acceder a nuevos espacios químicos.
- Los alquenos ofrecen una versátil reactividad radical C ((sp3) a través de la transferencia de átomos de hidrógeno de hidrógeno metálico (MHAT), pero sus aplicaciones de metalfotoredox son limitadas.
Objetivo del estudio:
- Desarrollar una nueva estrategia de foto-reducción de metales para el acoplamiento C ((sp3) - C ((sp3).
- Para permitir el acoplamiento cruzado de alquenos con alcoholes utilizando la activación MHAT.
- Establecer un sistema de cocatálisis triple para la hidroalquilación desoxigenativa.
Principales métodos:
- Utilizó un sistema sinérgico de cocatálisis triple que incluye fotorredóxido de iridio, MHAT de manganeso y clasificación de radicales de níquel.
- Transferencia de átomos de hidrógeno de hidrógeno metálico (MHAT) empleado para la activación de alquenos.
- Se ha investigado la hidroalquilación desoxigenativa de diversas olefinas con metanol y alcoholes primarios.
Principales resultados:
- Se informó del primer acoplamiento cruzado de alquenos activados por MHAT con alcoholes.
- Se ha logrado una hidroalquilación selectiva de las olefinas.
- Demostró una notable tolerancia funcional del grupo en el protocolo desarrollado.
Conclusiones:
- El protocolo de cocatálisis triple desarrollado permite la construcción rápida de estructuras alifáticas complejas.
- Este método amplía el alcance del acoplamiento cruzado con metales fotorredóxicos para la química medicinal.
- El sistema catalítico sinérgico ofrece una nueva herramienta poderosa para la síntesis orgánica.
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