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Generación de radicales alquilo a través de la excitación directa de alquilborato a base de boráceno
Yukiya Sato1, Kei Nakamura1, Yuto Sumida1,2
1Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Journal of the American Chemical Society
|May 13, 2020
Resumen
La excitación por luz visible de una molécula de organoboron genera radicales alquilo. Este método permite diversas formaciones de enlace carbono-carbono, introduciendo varios fragmentos de C ((sp3) en moléculas orgánicas.
Área de la Ciencia:
- Química orgánica
- La fotoquímica
- Química del organoboron
Sus antecedentes:
- Los radicales alquilo son intermediarios cruciales en la síntesis orgánica.
- La generación de radicales alquilo a menudo requiere condiciones duras o precursores específicos.
- La catálisis fotorredóxica con luz visible ofrece una alternativa más suave para la generación de radicales.
Objetivo del estudio:
- Desarrollar un nuevo método para generar radicales alquilo primarios, secundarios y terciarios.
- Para utilizar la excitación por luz visible de un alquilborato a base de boraceno para la generación de radicales.
- Demostrar la aplicabilidad de este protocolo en varias reacciones de formación de enlaces C-C.
Principales métodos:
- Excitación directa con luz visible de un alquilborato a base de boraceno.
- Caracterización fotofísica de la molécula de organoboron.
- Aplicación de radicales alquilo generados en reacciones de decanoalquilación, adición de Giese y acoplamiento cruzado catalizado por níquel.
Principales resultados:
- Generación exitosa de radicales alquilo terciarios, secundarios y primarios.
- Demostración de la versatilidad del protocolo en las reacciones de decanoalquilación y adición de Giese.
- Se logró un acoplamiento cruzado alquilo-arilo catalizado por níquel y una alquilarización vicinal de alquenos.
Conclusiones:
- La generación de radicales alquilo mediada por luz visible a partir de alquilboratos es una estrategia sintética viable.
- Este método proporciona acceso a diversos fragmentos de C ((sp3) para la síntesis orgánica.
- El protocolo ofrece un enfoque suave y eficiente para construir moléculas orgánicas complejas.
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