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Catálisis en tándem: generación de múltiples enlaces contiguos carbono-carbono a través de una metátesis de cierre de
Benjamin A Seigal1, Cristina Fajardo, Marc L Snapper
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Journal of the American Chemical Society
|November 17, 2005
Resumen
Los catalizadores de rutenio permiten la metátesis de cierre de anillo de olefinas en tándem y las reacciones de adición de Kharasch. Este proceso de un solo paso crea de manera eficiente complejos sistemas de anillos bicíclicos con múltiples estereocentros a partir de precursores simples.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- Química sintética de la química sintética.
Sus antecedentes:
- La catálisis en tándem ofrece rutas de síntesis eficientes, reduciendo los residuos y el manejo.
- Los catalizadores de rutenio son herramientas versátiles en la síntesis orgánica.
Objetivo del estudio:
- Desarrollar un nuevo protocolo catalítico en tándem utilizando un catalizador de rutenio.
- Para lograr la síntesis de complejos sistemas de anillos bicíclicos en una sola operación.
Principales métodos:
- Utilizando el catalizador de alquilideno de rutenio de Grubbs, (Cy3P) 2Cl2Ru=CHPh.
- Empleando una reacción en tándem que combina la metátesis de cierre de anillo de olefinas (RCM) y la adición de Kharasch.
- Investigando las vías de adición intramolecular e intermolecular de Kharasch.
Principales resultados:
- Sintetizó con éxito sistemas de anillos bicíclicos [3.3.0], [4.3.0] y [5.3.0].
- Demostró la formación de tres nuevos enlaces de carbono-carbono contiguos en un solo paso.
- Generó múltiples estereocentros a través de dos vías catalíticas distintas.
Conclusiones:
- El desarrollado en tándem protocolo de adición RCM/Kharasch proporciona un método potente y eficiente para la construcción de arquitecturas moleculares complejas.
- Esta estrategia de una sola olla minimiza los residuos y simplifica los procedimientos sintéticos.
- Las reacciones en tándem catalizadas por rutenio ofrecen ventajas significativas en la química sintética moderna.
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