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Reacción migratoria de 1,1-cicloannulación catalizada por Pd de los alquenos

Jin-Ping Wang^1,2, Tao Liu¹, Yichen Wu¹

¹State Key Laboratory of Organometallic Chemistry and Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, CAS 345 Lingling Road, Shanghai 200032, P. R. China.

Journal of the American Chemical Society

|December 18, 2024

Resumen

Una nueva reacción catalizada por el paladio permite la síntesis eficiente de diversos heterociclos de nitrógeno y oxígeno a partir de alquenos simples. Este método ofrece una amplia tolerancia de grupo funcional y control sobre el tamaño del anillo, simplificando la preparación de moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Química Heterocíclica

Sus antecedentes:

Los heterociclos son motivos estructurales cruciales en productos farmacéuticos y materiales.
Los métodos sintéticos eficientes y versátiles para la preparación de heterociclos son muy buscados.
Las reacciones catalizadas por el paladio ofrecen herramientas poderosas para la formación de enlaces C-C y C-heteroatomo.

Objetivo del estudio:

Desarrollar una nueva reacción migratoria de 1,1-cicloanulación catalizada por el paladio (MCAR).
Para sintetizar diversos heterociclos de aza y buey de cinco a siete miembros.
Explorar el alcance y las limitaciones de la nueva reacción con varios sustratos.

Principales métodos:

Se utilizó la catálisis de paladio para la reacción migratoria de 1,1-cicloannulación.
Utilizan aminas alqueniles y alcoholes alqueniles fácilmente disponibles como materiales de partida.
Se ha investigado el papel del 4-iodofenol o de los derivados del 2-iodofenol en el control de la regioselectividad y del tamaño del anillo.

Principales resultados:

Se preparó con éxito una amplia gama de azaheterociclos y oxaheterociclos de cinco a siete miembros.
Se ha demostrado una alta eficiencia y una buena tolerancia del grupo funcional en la reacción.
Identificó el papel crítico del grupo hidroxilo fenólico en la dirección de la migración y el control del tamaño del anillo a través de un intermediario de metido de quinona.

Conclusiones:

El MCAR catalizado por Pd desarrollado proporciona una estrategia novedosa y eficiente para la síntesis de heterociclos.
La reacción ofrece una plataforma versátil para acceder a diversas estructuras heterocíclicas.
La comprensión del mecanismo que involucra a los intermediarios de metido de quinona permite un control preciso sobre el proceso de cicloannulación.

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