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Catalizadores de molibdeno-alquilidina altamente activos para la metátesis de alquinos: síntesis a partir de los
Robyn L Gdula1, Marc J A Johnson
1Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.
Journal of the American Chemical Society
|July 27, 2006
Resumen
Los nuevos complejos de nitrido de molibdeno reaccionan con 3-hexina para formar complejos de propilidina. Estos complejos son catalizadores conocidos para las reacciones de metátesis de alquinos, con un aislamiento conveniente de los aductos.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
Sus antecedentes:
- Los complejos de nitrido de molibdeno son intermediarios clave en las reacciones de transferencia de nitrógeno.
- La metátesis alquina es una herramienta poderosa para la formación de enlaces carbono-carbono.
Objetivo del estudio:
- Para investigar la reactividad de los nuevos complejos de nitrido de molibdeno con alquinas internas.
- Para sintetizar y caracterizar los complejos de propilidina derivados de estas reacciones.
- Para explorar la utilidad de estos complejos como precursores de los catalizadores de la metátesis de alquinos.
Principales métodos:
- Reacción de complejos terminales de nitrido con 3-hexina a temperaturas elevadas.
- Aislamiento y caracterización de los complejos de propilidina resultantes.
- Formación de adutos de 1,2-dimetoxietano (DME) para mejorar la cristalización.
Principales resultados:
- Reacción irreversible de los complejos de nitrido NMo (((OC ((CF3) 2Me) 3 , NMo (((OC ((CF3) 2Me) 3 ((NCMe) y NMo (((OC ((CF3) 3) 3 ((NCMe) con 3-hexeno.
- Formación de complejos de propilidina EtCMo(OC(CF3)2Me)3 y EtCMo(OC(CF3)3)3.3.
- Aislamiento conveniente de los complejos de propilidina como aductos de DME, con 3-DME obtenido en un 61% de rendimiento en una escala multigrama.
Conclusiones:
- Los complejos de nitrido de molibdeno sirven como precursores efectivos para los complejos de propilidina.
- Los complejos de propilidina sintetizados son fácilmente aislables y potencialmente útiles en la metátesis de alquinos.
- Este trabajo proporciona una ruta conveniente a los catalizadores conocidos y altamente activos de la metátesis de alquinos.
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