L-ethyl-3-methyl imidazolium chloride

The imidazolium compounds l-ethyl-3-methyl-imidazolium-chloride (EMIM-Cl), l-butyl-3-methyl-imidazolium-chloride (n-BuMIM-Cl), and l-hexyl-3-methyl-imidazolium-chloride (n-HeMIM-Cl), toluene (anhydrous, 99.99%), and HCl were obtained from Sigma Aldrich whereas, l-octyl-3-methyl-imidazolium-chloride (n-OcMIM-Cl), l-Dodecyl-3-methyl-imidazolium-chloride (n-DoMIM-Cl) were... 

Rhinebarger et al. [35] and Eyring et al. [36,37] have used lithium-7 nuclear magnetic resonance (NMR) chemical shift data to determine the stability constants for crown-ether complexes of Li+ in two IL systems consisting of 55/45 mole% N-butylpyridinium chloride-aluminum chloride and l-ethyl-3-methyl-imidazolium chloride-aluminum chloride. The stability constants for... 

Seddon showed that l-ethyl-3-methyl imidazolium chloride-aluminum(lll) chlorides are ionic liquids at temperatures as low as -90°C (Seddon, 1996 Earle and Seddon, 2000). These nonvolatile ionic liquids can solvate a wide range of organic reactions including oligomerisations, polymerizations (Lynn et al., 2000), alkylations (Ross et al., 2001), and acylations (Seddon, 1997 Welton, 1999). 

Fig. 4.1 Simplified electrochemical windows of 1-butyl-pyridinium chloride and l-ethyl-3-methyl-imidazolium chloride.

The first work in this field was reported by Winnick et al. in 1995 [4], In order to design a sodium/iron(II) chloride battery, they examined a l-ethyl-3-methyl-imidazolium chloride/aluminum chloride-based system. As described by Lipsztajn and Osteryoung for lithium it was first necessary to synthesize the acidic ionic liquid by adding an excess of AICI3 and then adding an equivalent amount of sodium chloride as a buffer to obtain again the neutral species. 

Yeh FH, Tai CC, Huang JF et al (2006) Formation of porous silver by electrochemical alloying/ dealloying in a water-insensitive zinc chloride-l-ethyl-3-methyl imidazolium chloride ionic liquid. J Phys Chem B 110 5215-5220... 

The photoisomerization of cis-and trans-stilbenes has been studied in ionic liquids and evidence is presented that the mechanism depends on the particular ionic liquid used. In basic N-butylpyridinium chloride/AlCb the photoequilibration involves stilbene radical cations, whereas in basic l-ethyl-3-methyl-imidazolium chloride/AlCb the process occurs via the standard singlet state photoisomerization mechanism. It has been found that the tetra-O-acetylribo-flavin (126) sensitized dehydrogenation of substituted benzyl alcohols, giving the... 

Geometrical trans to cis isomerization of 3,3 -, 4,4 -, and 5,5 -disubstituted 2,2 -diphenoquinones has been studied by computational methods.The double bond isomerization of butene-catalysed l-ethyl-3-methyl-imidazolium chloride ionic liquid has been similarly examined and stepwise isomerization is suggested.The reaction of l,2-di(l-adamantyl)-2-thioxoethanone with diazomethane and 2-diazopropane gave 2-acylthiiranes via 2 - - 3-cycloaddition, elimination of nitrogen, and 1,3-dipolar electrocyclization of the intermediate acyl-substituted thiocarbonyl ylides. Rearrangement of pyrimidine-5-carboxylic acids esters to 5-acylpyrimidones does not occur in the examples studied and a [l,4]-phospho-Fries rearrangement has been reported. ... 

Phenothiazines contain positively charged amine groups in a mobile phase at low pH. Therefore, they are retained in the presence of ionic liquids through the combination of electrostatic interactions and hydrophobic effects. The effects of the concentration and the type of ionic liquid on the retention of the analyfes, peak symmetry, and efficiency were examined. The following trends increase the retention factor of the analytes and improve system efficiency 1-but-yl-3-methylimidazolium hexafluorophosphate > l-ethyl-3-methyl-imidazolium hexafluorophosphate > l-butyl-3-methylimidazolium chloride. 

No redox features are observed for VCI3 dissolved in l-ethyl-3-methyl-l//-imidazolium chloride (EMIC)/AlCl3 until excess Cl is added. The main species formed appears to be [VCl ] ", although [VCls] " and [VCU]" are also present, and these species may be oxidized reversibly... 

Smith, G.R, Dworkin, A.S., Ragni, R.M., Zingg, S.R, Bronsted superacidity of HCl in liquid chloroaluminate, A1C13—l-ethyl-3-methyl-lH-imidazolium chloride, J. Am. Chem. Soc., Ill, 525-529,1989. 

Campbell, J. L. E., Johnson, K. E., and Torkelson, J. R., Infrared and variable-temperature H-NMR investigations of ambient-temperature ionic liquids prepared by reaction of HCl with l-ethyl-3-methyl-lH-imidazolium chloride, Inorg. Chem., 33, 3340,1994. 

BPC) or l-ethyl-3-methyl-l/f-imidazolium chloride (EMIC), as solvent can accelerate DABCO-catalyzed MBH reactions that are sluggish for other ionic liquids. In addition, the combination of EMIC with AICI3 is a more efficient chloroaluminate ionic liquid than the BPC with AICI3, as it offers higher yields in comparatively shorter time (Scheme 1.119). The chloroaluminates can be easily recycled and reused six times without loss of activity. ... 

In one of the first studies, Stepnowski Zaleska compared the effectiveness of three methods UV photodegradation, UV photolysis of hydrogen peroxide, and photocatalysis on UV-irradiated Ti02. For these investigations imidazolium ILs with different alkyl chain length were chosen (1-butyl-, l-hexyl-3-methylimidazolium, l-methyl-3-octylimidazolium, l-ethyl-3-ethylimidazolium chloride or tetrafluoroborate, methyl imidazole as reference). The stability of these compoxmds with respect to all the photodegradation methods used... 

The last electrolyte system to be mentioned in connection with lithium electrodes is the room temperature chloroaluminate molten salt. (AlCl3 LiCl l-/ -3/ "-imidazolium chloride. R and R" are alkyl groups, usually methyl and ethyl, respectively.) These ionic liquids were examined by Carlin et al. [227-229] as electrolyte systems for Li batteries. They studied the reversibility of Li deposition-dissolution processes. It appears that lithium electrodes may be stable in these systems, depending on their acidity [227], It is suggested that Li stability in these systems relates to passivation phenomena. However, the surface chemistry of lithium in these systems has not yet been studied. 

Figure 45 Structure of l-(l-butyl) pyridinium chloride (BPC) and l-methyl-3 ethyl-imidazolium chloride (MEIC).

Pickup, R, and R.A. Osteryoung. 1985. Charging and discharging rate studies of polypyrrole films in AICI3 l-Methyl-(3-ethyl)-imidazolium chloride molten salts and in CH3CN. JElectroanal Chem 195 271. 

The variation of density with different concentrations of aluminum trichloride in 1,3-dialkylimidazolium chloride- aluminum chloride melts is not however a smooth function. In the study carried out by Wilkes et al. on the density of l-methyl-3-ethyl-imidazolium bromide aluminum bromide systems, the change of the parameters a and b with composition, X, were successfully fitted to polynomials of third order. The constants obtained from this study are shown in Table 21.2.14. 

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