دورية
The Importance of Imidazolium Substituents in the Use of Imidazolium-Based Room-Temperature Ionic Liquids as Solvents for Palladium-Catalyzed Telomerization of Butadiene with Methanol
| العنوان: | The Importance of Imidazolium Substituents in the Use of Imidazolium-Based Room-Temperature Ionic Liquids as Solvents for Palladium-Catalyzed Telomerization of Butadiene with Methanol |
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| المؤلفون: | Magna, L., Chauvin, Y., Niccolai, G. P., Basset, J.-M. |
| المصدر: | Organometallics; October 2003, Vol. 22 Issue: 22 p4418-4425, 8p |
| مستخلص: | Room-temperature ionic liquids are used as cosolvents in the palladium-catalyzed telomerization of butadiene with methanol. The basic catalyst is palladium(II) acetate with either triphenylphosphine or sodium diphenylphosphinobenzene-3-sulfonate (TPPMS), which was reacted with butadiene and methanol at 85 °C. It was found that the addition of several equivalents of 1,3-dialkylimidazolium salts per palladium leads to complete deactivation of the catalyst. It was suspected that the deactivation of the catalyst was due to the formation of highly stable palladium imidazolylidene complexes, but no direct evidence of this species was obtained. On the basis of this hypothesis, the use of pyridinium and 1,2,3-trialkylimidazolium salts was studied in an attempt to limit the formation of such species. It was found, particularly for the 1,2,3-trialkylimidazolium salts, that highly active and selective systems for the telomerization of butadiene with methanol were obtained. Furthermore, a biphasic catalytic system composed of palladium(II) acetate, TPPMS, heptane, and 1-butyl-2,3-dimethylimidazolium bis((trifluoromethyl)sulfonyl)imidate, [BMMI][TF |
| قاعدة البيانات: | Supplemental Index |
Find this issue from the American Chemical Society | تدمد: | 02767333 15206041 |
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