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Calcio quiral VAPOL fosfato mediado por cloración asimétrica y reacciones de Michael de oxindoles 3-sustituidos

Wenhua Zheng¹, Zuhui Zhang, Matthew J Kaplan

¹Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States.

Journal of the American Chemical Society

|February 24, 2011

Resumen

Un nuevo catalizador quiral de fosfato de calcio VAPOL permite una cloración altamente enantioselectiva de oxindoles 3-sustituidos utilizando N-clorosuccinimida. Este método también cataliza de manera eficiente las adiciones Michael enantioselectivas de 3-ariloxindoles.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

Los catalizadores quirales son cruciales para la síntesis enantioselectiva.
Los derivados del oxindol son importantes componentes de la industria farmacéutica.
El desarrollo de métodos catalíticos eficientes para la funcionalización de los oxindoles es altamente deseable.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico para la cloración enantioselectiva de oxindoles 3-sustituidos.
Explorar la utilidad del catalizador desarrollado en otras transformaciones asimétricas, como las adiciones de Michael.

Principales métodos:

Utilizó un complejo quiral de fosfato de calcio VAPOL como catalizador.
Se empleó N-clorosuccinimida (NCS) como agente clorante.
Investigó la adición enantioselectiva de Michael de 3-aryloxindoles a la cetona de metil vinilo. investigado la adición enantioselectiva de Michael de 3-aryloxindoles a la cetona de metil vinilo.

Principales resultados:

Se obtienen altos rendimientos y una excelente enantioselectividad en la cloración de varios oxindoles 3-sustituidos.
Demostró la efectividad del catalizador para promover la reacción asimétrica de adición de Michael con un alto enantiocontrol.
Se establecieron condiciones de reacción suaves y eficientes para ambas transformaciones.

Conclusiones:

El catalizador quiral de fosfato de calcio VAPOL desarrollado es una herramienta poderosa para la cloración asimétrica y las reacciones de adición de Michael.
Esta metodología proporciona una ruta práctica y escalable a los derivados de oxindole enriquecidos enantioméricamente.
Los hallazgos abren nuevas vías para la síntesis de moléculas quirales complejas que contienen el andamio oxindole.

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