Ethyl tetrachloroaluminate

From empirical observation, ILs tend to be immiscible with non-polar solvents. They can therefore be washed or brought into contact with diethyl ether or hexane to extract non-polar reaction products. Among solvents of greater polarity, esters (ethyl acetate, for example) exhibit variable solubility with ILs, depending on the nature of the IL. Polar or dipolar solvents (including chloroform, acetonitrile, and methanol) appear to be totally miscible with all ILs (excepting tetrachloroaluminate IL and the like, which react). Among notable exceptions, [EMIMJCl and [BMIMJCl are insoluble in dry acetone. 

The utility of ionic liquids can primarily be traced to the pioneering work by Osteryoung et al. [3] on N-butylpyridinium-containing, and by Wilkes and Hussey [4—6] on l-ethyl-3-methylimidazoHum-containing ionic Hquids for electrochemical studies. These studies have strongly influenced the choice of ionic Hquids for subsequent research [7]. The vast majority of work pubHshed to date on room-temperature ionic Hquids relates to N-butylpyridinium and l-ethyl-3-methyHmidazoHum [EMIM] tetrachloroaluminate(III) systems. The large variety of available ion combi-... 

Piersma et al. demonstrated that lithium can be electrodeposited from 1-ethyl -3-methyl-imidazolium tetrachloroaluminate ionic liquid, when lithium chloride was dissolved in the melt [3], Platinum, glassy carbon and tungsten were used as working electrodes with molybdenum and platinum foils as counter electrodes. At -2.3 V a reduction peak of Li+ is observed and at about -1.6 V the stripping of lithium occurs. They noticed that the efficiency was much less than 100%. In addition, they were able to demonstrate that the addition of proton sources like triethanolamine-HCl widens the electrochemical window and allows the plating and stripping of lithium (and also sodium). 

This method is not only limited to halide-based ionic liquids. Synthesis of ionic liquids containing a tetrafluoroborate anion and imidazolium cation has been performed successfully [16] by use of a modified domestic microwave oven with pulsed irradiation (5 x 30 s). Approximately 90% yields of the desired ionic liquids were usually obtained compared with 36% after the same reaction time using conventional heating. Microwave irradiation has been used in the synthesis of l-ethyl-3-methylimidazolium benzoate and dialkyl imidazolium tetrachloroaluminate ionic liquids [17, 18]. These reactions were again performed in a domestic microwave oven using pulsed irradiation. 

Liquid State Simulations on Room Temperature Molten Salts l-Ethyl-3-methylimidazolium Tetrachloroaluminate. 

Plate 9 H NMR spectrum of 1-Ethyl-3-methylimidazolium tetrachloroaluminate [emim]AlCU Solvent CDCb... 

Computer simulation studies of the structure of molten RTILs require suitable force fields of the constituent ions. Such a force field was supplied in the case of l-ethyl-3-methylimidazolium tetrachloroaluminate by Andrade et al. [32] and the molecular dynamics simulation was tested against the structure determined by... 

J. de Andrade, E. Boes and H. Stassen. A force field for liquid state simulations on room temperature molten salts l-Ethyl-3-methylimidazolium tetrachloroaluminate. J. Phys. Chem. B 106, 2002, 3546. 

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