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Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
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Formación radical monovalente mediada por níquel: una vía concertada de disociación halógeno-atomo determinada por
1Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States.
Journal of the American Chemical Society
|August 25, 2021
Resumen
Los catalizadores de níquel activan electrófilos C ((sp3) a través de una transferencia de electrones en la esfera interna y un mecanismo de disociación de átomos de halógeno. Esta vía explica la reactividad y la quimioselectividad en las reacciones de acoplamiento cruzado.
Área de la Ciencia:
- Química organometálica
- Catálisis
- Síntesis orgánica
Sus antecedentes:
- Las especies monovalentes de níquel son clave para activar electrófilos C ((sp3) en reacciones de acoplamiento cruzado.
- La comprensión del mecanismo de esta activación es crucial para el desarrollo de catalizadores.
Objetivo del estudio:
- Para elucidar el mecanismo por el cual los catalizadores de (bpy) Ni activan electrófilos C ((sp3).
- Diferenciar entre las vías de activación propuestas.
Principales métodos:
- Estudios electroanalíticos del catalizador (bpy) Ni.
- Análisis de la relación de energía libre lineal.
- Cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- Se descartó la transferencia de electrones de la esfera externa y la adición oxidativa de dos electrones.
- Se apoyó una transferencia concertada de electrones en la esfera interna y un mecanismo de disociación de átomos de halógeno.
- Se explicó la reactividad y la quimioselectividad en el acoplamiento cruzado y el acoplamiento electrofilo cruzado.
Conclusiones:
- El estudio aclara el mecanismo de activación electrofílica de C ((sp3) por catalizadores de níquel.
- Esta comprensión proporciona una justificación para el rendimiento del catalizador y la selectividad en las reacciones de acoplamiento cruzado.
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