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Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
Catalizador de metátesis de olefinas basado en rutenio, sencillo y altamente selectivo en Z
Giovanni Occhipinti1, Fredrik R Hansen, Karl W Törnroos
1Department of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway.
Journal of the American Chemical Society
|February 13, 2013
Resumen
Un nuevo catalizador de Grubbs-Hoveyda con un ligando de trifenilbenzenetiolato demuestra una alta selectividad Z en la metátesis de olefinas. Este robusto catalizador logra excelentes números de rotación y mantiene la selectividad Z, ofreciendo una herramienta prometedora para la síntesis de olefinas.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La metátesis de olefinas es una herramienta poderosa para la formación de enlaces C=C.
- Los catalizadores de segunda generación Grubbs-Hoveyda son ampliamente utilizados, pero a menudo carecen de una alta selectividad Z.
- El desarrollo de catalizadores con una estereoselectividad mejorada es crucial para la síntesis dirigida.
Objetivo del estudio:
- Para sintetizar y caracterizar una nueva variante del catalizador Grubbs-Hoveyda.
- Evaluar la actividad catalítica y la selectividad Z del nuevo catalizador en la metátesis de olefinas.
- Para comparar el rendimiento y las propiedades del nuevo catalizador con su compuesto madre.
Principales métodos:
- Sustitución en un solo paso del ligando cloruro en el catalizador de segunda generación Grubbs-Hoveyda.
- Síntesis del ligando 2,4,6-trifenilbenzenetiolato.
- Reacciones de metátesis de olefinas, incluyendo el homoacoplamiento de las olefinas terminales.
- Análisis de la selectividad Z y números de facturación.
Principales resultados:
- Se sintetizó con éxito un nuevo catalizador mediante la sustitución de un anión de cloruro por un ligando de 2,4,6-trifenilbenzenetiolato.
- El nuevo catalizador exhibió una notable selectividad Z, logrando hasta un 96% en el homoacoplamiento de las olefinas terminales.
- Se observaron altos números de rotación (hasta 2000) y una selectividad Z sostenida (>85%).
- El catalizador demostró robustez hacia el oxígeno y el agua, similar al catalizador padre.
Conclusiones:
- El nuevo catalizador Grubbs-Hoveyda con un ligando de trifenilbenzenetiolato es altamente efectivo para la metátesis de olefinas Z-selectivas.
- Este catalizador ofrece una valiosa alternativa para la síntesis de Z-olefinas con alta eficiencia y selectividad.
- Su robustez y características de rendimiento lo hacen adecuado para diversas aplicaciones sintéticas.
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