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Comprensión de la quimioselectividad en la transferencia de electrones acoplados a protones: un estudio cinético de

Guanqi Qiu¹, Robert R Knowles¹

¹Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States.

Journal of the American Chemical Society

|October 2, 2019

Resumen

Este estudio cuantifica la quimioselectividad en las reacciones de transferencia de electrones acoplados a protones (PCET), revelando cómo las constantes de velocidad y el enlace de hidrógeno controlan la selectividad en las activaciones de amida y tiol para la hidroamidación.

Área de la Ciencia:

La cinética química
Catálisis
Química orgánica

Sus antecedentes:

La transferencia de electrones acoplados a protones (PCET) es crucial en las reacciones químicas.
La comprensión de los factores que controlan la quimioselectividad en el PCET es limitada.
El PCET es relevante para la hidroamidación catalítica de las olefinas.

Objetivo del estudio:

Proporcionar una base cuantitativa para la comprensión de la quimioselectividad en las activaciones PCET competitivas de amidas y tiolos.
Investigar la interacción de los factores cinéticos y termodinámicos en la quimioselectividad del PCET.
Informar estrategias para mejorar las reacciones de PCET en catálisis.

Principales métodos:

Estudio cinético de las reacciones PCET competitivas.
Análisis de los equilibrios de enlace de hidrógeno.
Análisis de la relación de fuerzas que impulsan la tasa.

Principales resultados:

Demostró cómo las constantes de velocidad de PCET, los equilibrios de enlace de hidrógeno y las relaciones de fuerza que impulsan la velocidad determinan conjuntamente la quimioselectividad.
Tendencias de reactividad previstas en un modelo de reacción de hidroamidación.
Activación selectiva racionalizada de los enlaces N-H de amida sobre los enlaces S-H de tiol.

Conclusiones:

La quimioselectividad en el PCET está regida por una combinación de factores cinéticos y termodinámicos.
Los resultados proporcionan un marco para el diseño de catalizadores PCET selectivos.
Se desarrollaron estrategias para mejorar la eficiencia de la reacción PCET utilizando co-catalizadores de tiol.

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