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Tandem Adición de Michael/Epoxidación de ilido para la síntesis de derivados de epóxido de ciclohexadieno altamente

Qing-Gang Wang¹, Xian-Ming Deng, Ben-Hu Zhu

¹State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, 354 FengLin Lu, Shanghai 200032, China.

Journal of the American Chemical Society

|April 2, 2008

Resumen

Los investigadores desarrollaron un nuevo método para sintetizar complejos derivados del epoxido de ciclohexadieno. Este proceso eficiente utiliza una adición/epoxidación de ylide Michael en tándem con catalizadores quirales, logrando una alta enantioselectividad.

Área de la Ciencia:

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

Sus antecedentes:

Los epoxidos de ciclohexadieno son valiosos intermediarios sintéticos.
Desarrollar métodos estereoselectivos para su síntesis es un desafío.

Objetivo del estudio:

Desarrollar una síntesis altamente eficiente y diastereoselectiva de derivados de epoxido de ciclohexadieno.
Para lograr una alta enantioselectividad en la síntesis de compuestos multi-esterocentros.

Principales métodos:

Se empleó una adición en tándem de ylide Michael seguida de una epoxidación.
Los ylidos de sulfonio quiral se utilizaron como reactivos clave.

Principales resultados:

El método desarrollado proporciona un acceso eficiente a los derivados del epoxido de ciclohexadieno.
Se observó una alta diastereoselectividad en las reacciones.
Se lograron enantioselectividades de hasta un 96% de exceso enantiomérico (ee).

Conclusiones:

El tándem de adición/epoxidación de ylide Michael es una poderosa estrategia para la síntesis de complejos epoxidos de ciclohexadieno.
El uso de ylidos quirales de sulfonio permite altos niveles de estereocontrol.

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