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Iluros de carbonilo inusualmente reactivos y selectivos para las reacciones de cicloadición de tres componentes

Andrew DeAngelis¹, Michael T Taylor, Joseph M Fox

¹Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.

Journal of the American Chemical Society

|January 9, 2009

Resumen

Este estudio detalla una nueva reacción catalizada por Rh que forma productos funcionalizados de furano. Los ylidos de carbonilo sustituidos por alquilo exhiben una reactividad más amplia y una alta selectividad en estas reacciones de tres componentes.

Área de la Ciencia:

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

Sus antecedentes:

Los ilidos de carbonilo son versátiles intermediarios en la síntesis orgánica.
Los métodos anteriores que utilizaban diazoacetato de etilo o alfa-arilo-alfa-diazoesters tenían limitaciones en el alcance y la reactividad.

Objetivo del estudio:

Desarrollar una nueva reacción de tres componentes catalizada por Rh para sintetizar derivados funcionalizados de dihidro y tetrahidrofurano.
Para explorar la reactividad de los ylidos de carbonilo sustituidos por alquilo.

Principales métodos:

Utilizó una reacción de tres componentes que involucra aldehídos, alfa-alquilo-alfa-diazoésteres y dipolarófilos.
Se empleó la catálisis de Rodio (Rh) para generar ylidos de carbonilo sustituidos por alquilo.
Reacciones de cicloadición investigadas de los ylidos generados.

Principales resultados:

Logró la formación de productos de dihidro- y tetrahidrofurano altamente funcionalizados.
Demostró un alcance más amplio de reactividad para los ylidos de carbonilo sustituidos por alquilo en comparación con los métodos anteriores.
Se observó una alta regioselectividad y diastereoselectividad en las reacciones.

Conclusiones:

El método desarrollado catalizado por Rh proporciona un acceso eficiente a estructuras complejas de furanos.
Los ylidos de carbonilo sustituidos por alquilo son intermediarios altamente reactivos y selectivos.
La selectividad observada puede explicarse mediante un modelo de estado de transición asíncrono y endoselectivo.

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