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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Síntesis de alquenos 1,1-disubstituidos a través de una adición catalizada por Ru
B M Trost1, A B Pinkerton, F D Toste
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
Journal of the American Chemical Society
|December 14, 2001
Resumen
Los complejos de rutenio catalizan la adición de alquinos a los alquenos, ofreciendo una ruta atómica económica a los alquenos 1,1-disubstituidos. Este nuevo método logra una alta regioselectividad y quimoselectividad en condiciones suaves.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los protocolos tradicionales de olefinación para sintetizar alquenos 1,1-disubstituidos a menudo sufren de una pobre economía atómica.
- El desarrollo de estrategias atómico-económicas es crucial para la síntesis química sostenible.
Objetivo del estudio:
- Explorar la adición catalizada por rutenio de alquinas terminales a los alquenos como una estrategia sintética de economía atómica.
- Descubrir nuevos complejos de rutenio que puedan catalizar eficientemente esta transformación.
Principales métodos:
- Cribado de complejos de rutenio para la adición de alquino-alqueno.
- Optimización de las condiciones de reacción, incluida la temperatura, la carga de disolvente y catalizador.
- Caracterización de los productos de reacción y estudios mecanicistas.
Principales resultados:
- Se identificaron dos nuevos complejos de rutenio, el camporsulfonato de ciclopentadienilrutenio (trifenilfosfina) y el trisulfonato de ciclopentadienilrutenio (acetonitrilo) hexafluorofosfato.
- Las reacciones proceden eficientemente a temperatura ambiente en acetona o DMF, respectivamente.
- Se observó una alta regioselectividad (9: 1 a > 25: 1) para alquenos 1,1-disubstituidos y una excelente quimioselectividad, tolerando varios grupos funcionales.
Conclusiones:
- La reacción catalizada por rutenio desarrollada proporciona un método atómico económico y altamente selectivo para sintetizar alquenos 1,1-disubstituidos.
- El mecanismo probablemente involucra un intermediario de metallaciclopenteno reversible, con quimioselectividad y regioselectividad regidas por factores cinéticos y termodinámicos.
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