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Hidroacilación catalizada por carbenos N-heterocíclicos de enlaces dobles no activados

Keiichi Hirano¹, Akkattu T Biju, Isabel Piel

¹Organisch-Chemisches Institut der Westfälischen Wilhelms-Universität Münster, Corrensstrasse 40, 48149 Münster, Germany.

Journal of the American Chemical Society

|October 8, 2009

Resumen

Un nuevo catalizador de carbenos N-heterocíclicos (NHC) permite la hidroacilación intramolecular de enlaces dobles no activados. Este nuevo método sintetiza de manera eficiente cromano-4-ones sustituidos, incluidos aquellos con centros cuaternarios de todo carbono desafiantes.

Área de la Ciencia:

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

Sus antecedentes:

Los carbenos N-heterocíclicos (NHC, por sus siglas en inglés) son organocatalizadores versátiles.
Las reacciones de hidroacilación son cruciales para la formación de enlaces C-C.
Los bonos dobles no activados presentan un desafío sintético.

Objetivo del estudio:

Para desarrollar una nueva reacción de hidroacilación intramolecular.
Para utilizar la catálisis NHC para la síntesis de cromano-4-ones.
Explorar el alcance y las limitaciones de la metodología desarrollada.

Principales métodos:

Hidroacilación intramolecular de alquenos no activados.
Variación y optimización sistemática de las estructuras del catalizador NHC.
Síntesis y caracterización del cromano-4-ones. sustituido.

Principales resultados:

Un N-mesitiltiazolilideno anulado con un anillo de siete miembros demostró una alta reactividad.
El catalizador NHC permitió la formación eficiente de enlaces C-C.
Se obtuvieron cromano-4-ones sustituidos en rendimientos de moderados a excelentes.
La reacción formó con éxito centros cuaternarios de todo carbono.

Conclusiones:

Se ha establecido una nueva y eficiente hidroacilación intramolecular catalizada por NHC.
El método desarrollado proporciona acceso a valiosos andamios de cromano-4-uno.
Esta metodología ofrece una poderosa herramienta para la construcción de moléculas orgánicas complejas.

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