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Características mecánicas clave de la fluoración desconstructiva mediada por plata de aminas cíclicas: reactividad en
Jose B Roque1, Richmond Sarpong1, Djamaladdin G Musaev2
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|March 3, 2021
Resumen
Este estudio revela un nuevo mecanismo de fluoración deconstructiva mediada por AgI para aminas cíclicas utilizando Selectfluor. La reacción procede a través de la reactividad de dos estados (TSR) que implica la abstracción de hidrógeno y la escisión del enlace C-C.
Área de la Ciencia:
- Química organometálica
- Reacciones de fluoración
- Química computacional
Sus antecedentes:
- La fluoración deconstructiva de aminas cíclicas es una transformación sintéticamente valiosa.
- Comprender los mecanismos de reacción es crucial para optimizar las estrategias sintéticas.
- La catálisis de plata ofrece vías de reactividad únicas en la síntesis orgánica.
Objetivo del estudio:
- Para elucidar el mecanismo de fluoración de las aminas cíclicas N-benzoiladas mediada por Ag (I) con Selectfluor.
- Investigar el papel de la reactividad de dos estados (TSR) en las transformaciones observadas.
- Para explorar posibles vías de reacción competidoras.
Principales métodos:
- Se utilizaron cálculos funcionales de densidad para modelar la vía de reacción.
- Se realizó un análisis de los estados electrónicos (singlet y triplet) de los productos intermedios.
- Se examinaron los principales pasos mecánicos, incluida la abstracción de hidrógeno y la escisión de enlaces C-C.
Principales resultados:
- Se propuso un mecanismo de fluoración deconstructiva mediado por AgI, iniciado por la asociación de reactivos.
- La reacción procede a través de una vía de reactividad de dos estados (TSR) que implica la abstracción de hidrógeno y la escisión del enlace C-C.
- Se identificó una vía de fluoración deformilante competidora.
Conclusiones:
- El estudio proporciona evidencia computacional de un nuevo mecanismo de fluoración catalizado por Ag.
- La reactividad de dos estados (TSR) juega un papel importante tanto en las vías primarias como en las competidoras.
- Los resultados ofrecen información sobre la compleja reactividad del Selectfluor en reacciones mediadas por metales.
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