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Metátesis catalítica metallonitreno/alquina: un poderoso proceso en cascada para la síntesis de moléculas que
Aaron R Thornton1, Simon B Blakey
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Journal of the American Chemical Society
|March 22, 2008
Resumen
Una nueva reacción catalizada por el rodio construye eficientemente compuestos que contienen nitrógeno utilizando alquinas simples. Esta cascada de metátesis metalonitreno/alquina crea enlaces C-N y complejas estructuras bicíclicas a temperatura ambiente.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los compuestos que contienen nitrógeno son cruciales en los productos farmacéuticos y la ciencia de los materiales.
- La síntesis eficiente de heterociclos complejos de nitrógeno sigue siendo un desafío.
- Las reacciones de metátesis ofrecen potentes herramientas para la formación de enlaces C-C y C-heteroátomo.
Objetivo del estudio:
- Desarrollar una nueva reacción en cascada para sintetizar compuestos que contienen nitrógeno.
- Para utilizar materiales de partida simples de alquino para una construcción molecular eficiente.
- Para explorar la catálisis del rodio para la metátesis de metallonitreno/alquino.
Principales métodos:
- Desarrollo de una reacción catalizada por tetracarboxilato de rodio.
- El atrapamiento de un intermediario electrófilo de nitreno de rodio por un alquino.
- Reacción en cascada que involucra la formación de enlaces C-N y la generación de metalocarbenos.
Principales resultados:
- Construcción exitosa de compuestos que contienen nitrógeno a través de una nueva reacción en cascada.
- La reacción es tolerante a diversos sustitutos de alquilo y arilo en las alquinas.
- Síntesis eficiente de sistemas bicílicos congestionados lograda a temperatura ambiente.
- Modularidad demostrada para la síntesis rápida de estructuras complejas.
Conclusiones:
- Se ha establecido una reacción en cascada de metástasis de metallonitreno/alquino conceptualmente nueva.
- Los catalizadores de rodio (II) permiten la formación eficiente de enlaces C-N y las subsiguientes transformaciones en cascada.
- La metodología proporciona una ruta versátil para moléculas nitrogenadas complejas a partir de precursores simples.
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