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Síntesis catalítica de arenas n-alquilo a través de la metátesis cruzada de grupos alquilo
Graham E Dobereiner1, Jian Yuan, Richard R Schrock
1Department of Chemistry, 6-331, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 6, 2013
Resumen
Este estudio introduce un novedoso método de una sola olla para sintetizar arenas n-alquilo a partir de alcanos simples. El proceso utiliza catalizadores de iridio y tungsteno para una alta selectividad y eficiencia en las reacciones en tándem.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La síntesis tradicional de arenas n-alquilo a menudo implica múltiples pasos y condiciones difíciles.
- El desarrollo de sistemas catalíticos eficientes para la funcionalización directa de alcano es un desafío clave en la síntesis orgánica.
Objetivo del estudio:
- Desarrollar una reacción en tándem de una sola olla para la síntesis directa de n-alquilarenos a partir de alcanos y etilbenceno.
- Investigar la eficacia de un sistema catalítico específico de iridio-tungsteno para esta transformación.
- Para explorar el potencial de los catalizadores de metatesis de olefinas altamente activos y térmicamente estables.
Principales métodos:
- Una secuencia en tándem de una sola olla que incluye deshidrogenación, metátesis de olefinas e hidrogenación.
- Utilizado ((tBu) PCP) IrH2 en combinación con los complejos de pyrrolide del monoaryloxide del tungsteno, específicamente W ((NAr) ((C3H6) ((pyr) ((OHIPT) (1a).
- Investigó la auto-metátesis del n-octano utilizando el complejo 1a bajo diversas condiciones.
Principales resultados:
- Se logró la síntesis directa de n-alquilarenos a partir de alcanos y etilbenceno con una excelente selectividad.
- El complejo 1a demostró una alta actividad en la auto-metátesis de n-octano, produciendo las concentraciones de producto más altas reportadas hasta la fecha.
- La estabilidad térmica de los catalizadores permitió el uso de temperaturas elevadas y tiempos de reacción prolongados.
Conclusiones:
- La reacción en tándem desarrollada de una sola olla ofrece una ruta eficiente a los n-alquilarenos.
- La combinación sinérgica de catalizadores de iridio y tungsteno proporciona una alta selectividad y actividad.
- Esta metodología representa un avance significativo en la funcionalización catalítica de alcano y la metátesis de olefinas.
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