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La aminoalquilación en tándem intramolecular catalizada por el paladio (II) a través de la funcionalización

Wei Du¹, Qiangshuai Gu, Zhongliang Li

¹Department of Chemistry, The University of Hong Kong , Pokfulam Road, Hong Kong, P. R. China.

Journal of the American Chemical Society

|December 27, 2014

Resumen

Este estudio introduce una nueva reacción catalizada por paladio para crear indolinas fusionadas utilizando la funcionalización C(sp(3)) -H. Este enfoque de química verde evita reactivos prefuncionalizados y grupos de dirección, ofreciendo una síntesis eficiente de heterociclos que contienen N.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La funcionalización C(sp(3)) -H es una estrategia clave en la síntesis orgánica.
La catálisis con paládio ofrece vías eficientes para la activación de C-H.
El desarrollo de nuevas reacciones en tándem es crucial para la síntesis simplificada.

Objetivo del estudio:

Desarrollar una nueva reacción de aminoalquilación en tándem oxidativa catalizada por Pd(II).
Para lograr una funcionalización divergente C (((sp (((3)) -H para la construcción de indolinas fusionadas.
Establecer un protocolo ecológico y económico para la síntesis de heterociclos que contienen N sin reactivos prefuncionalizados o grupos de dirección.

Principales métodos:

Se utilizó un catalizador Pd(II) para la aminoalquilación en tándem oxidativa.
Empleó estrategias de funcionalización divergentes C (((sp(3)) -H.
Se llevaron a cabo estudios mecanicistas para determinar los pasos que determinan la velocidad.

Principales resultados:

Se han sintetizado con éxito indolinas fusionadas de tres y cinco anillos en buenos rendimientos.
Identificó el paso que determina la velocidad en la formación de anillos de tres miembros (clivado bencílico C-H).
Se determinó que la escisión de la amida α-C-H no determina la velocidad en la formación de anillos de cinco miembros.

Conclusiones:

Este trabajo presenta la primera reacción en tándem catalizada por Pd utilizando la activación C(sp(3)) -H sin reactivos prefuncionalizados ni grupos de dirección.
El protocolo desarrollado ofrece un método ecológico y económicamente viable para la construcción de heterociclos que contienen N.
Los conocimientos mecanicistas proporcionan una base para el desarrollo de estrategias de funcionalización C-H.

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