Ethylimidazolium

Cationic polyelectrolytes containing imidazole groups have been investigated by some researchers. Morawetz et alU4 first found that a cationic polymer, poly (l-vinyl-3-ethylimidazolium iodide), 65 (PQMelm), enhanced the hydrolyses of the negatively charged esters, i. e. NABA and 4-acetoxy-3-nitrobenzenesulfonate 66 (NABS). At intermediate pH, a large catalytic effect was observed and this was... 

Jeng EGS, Sun IW (1997) Electrochemistry of tellurium (IV) in the basic aluminum chloiide-l-methyl-3-ethylimidazolium chloride room temperature molten salt. J Electrochem Soc 144 2369-2374... 

Scheme 13.2 Ethylene insertion followed by elimination of 2-ethylimidazolium...

Mitchell, J. A., The Electrodeposition of Cobalt, Iron, Antimony and Their Alloys from Acidic Aluminum Chloride 1 -methyl-3-ethylimidazolium Chloride Room-Temperature Molten Salts, Ph.D. Dissertation, 1997, University of Mississippi University, MS. 

Stuff, J. R., Separation of cations in buffered l-methyl-3-ethylimidazolium chloride + aluminum chloride ionic liquids by ion chromatography, J. Chromatogr, 547,484-487,1991. 

Dymek, C. J., Grossie, D. A., Fratini, A. V., and Adams, W. W., Evidence for the presence of hydrogen bonded ion-ion interaction in the molten salt precursor, l-methyl-3-ethylimidazolium chloride, /. Molec. Struct., 213, 25-34,1989. 

Carper, W. R., Pflug, J. L., and Wilkes, J. S., Multiple spin probe NMR-studies of ionic structure in l-methyl-3-ethylimidazolium chloride AlClj molten-salts, Inorg. Chim. Acta, 193,201,1992. 

Dieter, K. M., Dymek, G. J., Heimer, N. E. et al., Ionic structure and interactions in l-methyl-3-ethylimidazolium chloride-AlClj molten-salts, /. Am. Chem. Soc., 110,2722,1988. 

A 1 2 mixture of l-methyl-3-ethylimidazolium chloride and aluminum trichloride, an ionic liquid that melts below room temperature, has been recommended recently as solvent and catalyst for Friedel-Crafts alkylation and acylation reactions of aromatics (Boon et al., 1986), and as solvent for UV/Vis- and IR-spectroscopic investigations of transition metal halide complexes (Appleby et al., 1986). The corresponding 1-methyl-3-ethylimidazolium tetrachloroborate (as well as -butylpyridinium tetrachlo-roborate) represent new molten salt solvent systems, stable and liquid at room temperature (Williams et al., 1986). 

Friedel-Crafts reactions in the ionic liquid system l-methyl-3-ethylimidazolium chlo-ride-aluminium(ni) chloride can be performed with excellent yields and selectivities, and in the case of anthracene, have been found to be reversible. This ionic liquid has been shown to demonstrate catalytic activity in reactions such as Friedel-Crafts acylations (Surette et al., 1996 Boon et al., 1986) alkylation reactions (Koch et al., 1976),... 

Comprehensive reviews describing the preparation, purification, and physical and electrochemical properties of these melts have been published [17-20]. The most popular systems are mixtures of A1C13 with either l-(l-butyl)pyridinium chloride (BupyCl) or 1 -methyl-3-ethylimidazolium chloride (MeEtimCl). These systems are very versatile solvents for electrochemistry because they are stable over a wide temperature range. In many ways they can be considered to be a link between conventional nonaqueous solvent/supporting electrolyte systems and conventional high-temperature molten salts. 

A cyclic voltammogram of the [FeBrJ-72- electrode reaction at a Pyrex glass/glassy carbon electrode in molten AlBr3-l-methyl-3-ethylimidazolium bromide at 60°C is displayed in Figure 17.5. 

Figure 17.5 Cyclic voltammogram of a 15.2 mM solution of Fe(III) at a Pyrex glass/ glassy carbon electrode in the 49.5-50.5 mol% AlBr3-l-methyl-3-ethylimidazolium bromide melt at 60°C. The sweep rate was 50 mV s1. [From I.-W. Sun, J. R. Sanders, and C. L. Hussey, J. Electrochem. Soc. 136 1415 (1989), with permission.]...

Figure 17.6 (a) Reverse normal pulse voltammogram, (b) current measured prior to the analysis pulse in (a), and (c) normal large-amplitude pulse voltammogram at a platinum electrode for a 13.4 mM solution of Ti(IV) in the 60-40 mol% AlCl3-l-methyl-3-ethylimidazolium chloride melt at 25°C. [From Ref. 68, with permission.]... 

Figure 17.12 Spectropotentiostatic experiment conducted with a 6.08 tnM solution of [Re3Cl,2]3 in the 49.0-51.0 mol% AlCl3-l-methyl-3-ethylimidazolium chloride melt at40°C using the cell shown in Figure 17.11. Applied potentials (V) (a) open circuit, (b) -0.266, (c) -0.303, (d) -0.325, (e) -0.340, (f) -0.352, (g) -0.364, (h) -0.383, (i) -0.405, (j) -0.550. Inset Nernst plot constructed from the spectra in this figure. [From S. K. D. Strubinger, I.-W. Sun, W. E. Cleland, and C. L. Hussey, Inorg. Chem. 29 993 (1990), with permission.]...

InSb is an important compound semiconductor of the III-V family for optoelectronic purposes. At room temperature the semiconductor has a direct band gap of 0.17 eV and a high mobility of charge carriers. Similar to GaAs, it was reported that InSb can be directly electrodeposited at 45 °C in the Lewis basic chloroin-date ionic liquid InCl3/l-methyl-3-ethylimidazolium chloride, to which SbCU was... 

Li et al. [93] have used l-ethylimidazolium trifluoroacetate, which is a Bronsted acidic ionic liquid, as a medium for the electropolymerization of aniline. They report that in this ionic liquid the oxidation potential of aniline is lower (0.58 V compared to 0.83 V in 0.5 M H2SO4) and that the growth rate of the polymer is increased. Further, the resultant films are smooth, strongly adhered to the Pt working electrode and are very electrochemically stable. Similar results have been reported by Liu et al. [92], who found that this was the best ionic liquid for the polymerization of aniline, compared to the unsatisfactory results observed in other protic ionic liquids 1-butylimidazolium tetrafluoroborate, 1-butylimidazolium nitrate and 1-butylimidazolium p-toluenesulfonate, as well as the l-butyl-3-methylimidazolium hydrogen sulfate and l-butyl-3-methyimidazolium dihydrogen phosphate. 

In 1948, Frank Hurley and Thomas Wier, Jr. [433-436] obtained the first haloaluminate molten salts which melted at room temperature. The authors intended to use these salts as electroplating baths. These first room temperature melts were obtained by combining aluminum chloride with certain organic halide salts. Today, the most useful room temperature molten salts consist of mixtures of aluminum chloride with l-(l-butyl)pyridinium chloride (BPC) or l-methyl-3-ethylimidazolium chloride (MEIC). The structures of BPC and MEIC are given... 

The IL polymers were prepared from polymerizable anions and free imidazolium cations. To investigate the effect of the anion structure on the properties, four kinds of IL monomers were synthesized by neutralizing A-ethylimidazole with acryhc acid, -styrenesulfonic acid, vinylsulfonic acid, and vinylphosphonic acid, respectively, as shown in Figure 29.6 [32]. Table 29.1 summarizes the properties of IL monomers composed of the polymerizable anion and an ethylimidazolium cation. They are liquid at room temperature and show quite low Tg s in the range of —100 to —60°C. EImVS showed the lowest Tg of 95°C among these four IL monomers. In addition it showed the highest ionic conductivity of about 10 S cm at 30°C, which is comparable to that of the best ILs such as the l-ethyl-3-methylimidazolium salts. 

Treatment of the adenine derivative 1.84 with l-(benzyloxycarbonyl)-3-ethylimidazolium tetrafluoroborate (Rapoport s reagent 1.85) forms 1.86 in 82% yield in which the NH2 group is protected with Cbz. 

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