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Anulación en tándem catalizada por el rodio y (5 + 1) cicloadición: 3-hidroxi-1,4-enino como el componente de 5

Xiaoxun Li¹, Wangze Song, Weiping Tang

¹School of Pharmacy, University of Wisconsin , Madison, Wisconsin 53705, United States.

Journal of the American Chemical Society

|October 30, 2013

Resumen

Una nueva reacción catalizada por Rh crea eficientemente carbazoles y dibenzofuranos sustituidos utilizando un nuevo componente de 5 carbonos en una anulación en tándem y (5 + 1) cicloadición.

Área de la Ciencia:

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

Sus antecedentes:

Desarrollar rutas sintéticas eficientes para compuestos heterocíclicos complejos sigue siendo un desafío clave en la química orgánica.
Las reacciones en tándem y las cicloadiciones ofrecen poderosas estrategias para construir complejidad molecular en un solo paso.

Objetivo del estudio:

Desarrollar una nueva anulación en tándem catalizada por Rh y (5 + 1) reacción de cicloadición.
Para utilizar un 3-hidroxi-1,4-enino único como un bloque de construcción de cinco carbonos para la cicloadición.

Principales métodos:

El empleo de un catalizador de rodio para mediar una anulación en tándem y (5 + 1) proceso de cicloadición.
Utilizando 3-hidroxi-1,4-eninas como sustratos versátiles para la cicloadición.

Principales resultados:

Síntesis eficiente de carbazoles sustituidos, dibenzofuranos y compuestos tricíclicos que contienen una fracción de ciclohexadienona.
Aplicación exitosa de la estrategia de cicloadición (5 + 1) con el nuevo componente de cinco carbonos.

Conclusiones:

La reacción en tándem catalizada por Rh desarrollada proporciona una vía eficiente a valiosos andamios heterocíclicos.
La formación de un subproducto sugiere la participación de carbenos metálicos y cetenos intermedios en el mecanismo de cicloadición (5 + 1).

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