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La expansión del anillo catalizada por oro (I) de los ciclopropanolos y ciclobutanolos

Jordan P Markham¹, Steven T Staben, F Dean Toste

¹Department of Chemistry, University of California, Berkeley, California 94720, USA.

Journal of the American Chemical Society

|July 7, 2005

Resumen

Los complejos de oro ((I) catalizan la reorganización de los alquinyl ciclopropanols en alquilideno cicloalkanones. Esta reacción estereoselectiva proporciona un método práctico para sintetizar las ciclopentanonas sustituidas a partir de los ciclopropanolos.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química organometálica Química orgánica de los metales.
La catálisis es la catálisis.

Sus antecedentes:

El ciclopropanol y los derivados del ciclobutanol son valiosos intermediarios sintéticos.
Las reacciones catalizadas por oro ofrecen una reactividad y selectividad únicas en la síntesis orgánica.
La síntesis estereoselectiva de compuestos cíclicos complejos sigue siendo un desafío significativo.

Objetivo del estudio:

Para describir una nueva reorganización catalizada por oro ((I) de 1-alquinilo ciclobutanolos y ciclopropanolos.
Investigar el alcance y las limitaciones de esta transformación.
Establecer un método estereoselectivo para la síntesis de ciclopentanonas sustituidas.

Principales métodos:

Utilizando complejos catiónicos de triarilfosfina oro (I) como catalizadores.
Reaccionan 1-alquinil ciclobutanolos y ciclopropanolos bajo catálisis de oro.
Analizando el resultado estereoquímico de los productos de reordenamiento.

Principales resultados:

El reordenamiento catalizado por oro (I) convierte de manera eficiente los ciclopropanolos en alquilideno cicloalcanonas.
La reacción tolera varios sustituyentes en la posición acetilénica, incluidos los grupos alquilo, arilo y halo.
La transformación es estereoselectiva, dando un solo isómero de olefina y es estereospecífica con respecto a los sustituyentes de anillo.

Conclusiones:

La catálisis Gold (I) proporciona una vía práctica y estereoselectiva para las ciclopentanonas altamente sustituidas de los ciclopropanolos.
La reacción procede a través de la expansión secuencial del anillo catalizado por el oro.
Este método ofrece una herramienta valiosa para la construcción de estructuras cíclicas complejas con un preciso control estereoquímico.

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