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Mecanismo y estereoquímica de catalizar con rodio [5 + 2 + 1] Cicloadición de Ene-Vinylcyclopropanes y monóxido de

Yi Wang¹, Wei Liao¹, Yuanyuan Wang¹

¹Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, People's Republic of China.

Journal of the American Chemical Society

|February 7, 2022

Resumen

Este estudio aclara el mecanismo de las reacciones de cicloadición catalizadas por rodio [5 + 2 + 1]. El análisis cinético visual y los cálculos químicos cuánticos revelan el ciclo catalítico, incluidas las especies monoméricas activas y la escisión del ciclopropano que limita el volumen de negocios.

Área de la Ciencia:

Química organometálica
Catálisis
Química orgánica sintética

Sus antecedentes:

Las reacciones de cicloadición catalizadas por el rodio [5 + 2 + 1] sintetizan carbociclos de ocho miembros.
Esta reacción se ha aplicado en la síntesis de productos naturales.

Objetivo del estudio:

Investigar el mecanismo de la cicloadición [5 + 2 + 1] catalizada por el rodio de los enevinilciclopropanos (ene-VCP) y el monóxido de carbono.
Comprender los factores que influyen en la selectividad y la reactividad en este ciclo de adición.

Principales métodos:

Análisis cinético visual durante 15 años.
Cálculos químicos cuánticos de alto nivel (DLPNO-CCSD)

Principales resultados:

Se identificó un estado de reposo dimérico y una especie catalítica activa monomérica.
Detallado el ciclo catalítico: escisión de ciclopropano (limitando el volumen de negocios), inserción de alceno, inserción de CO, eliminación reductora y transferencia de catalizador.
Se explicaron los orígenes estéricos de la diastereoselectividad y los efectos de la configuración de doble enlace de VCP en la reactividad y la quimioselectividad.

Conclusiones:

El estudio proporciona una comprensión mecanicista completa de la cicloadición [5 + 2 + 1].
Los resultados ayudarán a comprender otras anulaciones carbonilativas catalizadas por metales de transición.

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