1,3-Dialkylimidazolium chloride-aluminum

Aluminum alkyl, 27 236 Aluminum chloride, 27 250 Aluminum chloride-1,3-dialkylimidazolium chloride catalyst system, 42 495—496 Aluminum oxide, 27 268, 269, 32 57-58, 34 195-197... 

Wilkes, J. S., Frye, J. S., and Reynolds, G. F., W1 and C NMR-studies of aluminum-chloride dialkylimidazolium chloride molten salts, Inorg. Chem., 22, 3870,1983. 

The class of organochloroaluminate ionic liquids, typically a mixture of a quaternary ammonium salt such as 1,3-dialkylimidazolium chloride with aluminum chloride (14), is the most widely explored system 122). 

Significant developments were achieved with the discovery in the 1970s and 1980s of varied room-temperature ionic liquids.41,42 These were organoaluminate ionic liquids, typically a mixture of quaternary ammonium salts with aluminum chloride. A major breakthrough came in 1992 by the discovery of air- and moisture-stable ionic liquids.43 1,3-Dialkylimidazolium cations (1), specifically,... 

These ILs can be turned acidic by adjusting the amount of aluminum chloride Raman spectroscopy showed [9] that at AlClj/dialkylimidazolium molar ratios greater than 1, polynuclear AI2CI7 and AljClfo anions appear. They can dissociate into AICI4 and the Lewis acid AICI3. 

Fannin, A.A., Floreani, D.A., King, L.A., Landers, J.S., Piersma, B.J., Stech, D.J., Vaughn, R. L., Wilkes, J.S., Williams, J.L. Properties of 1,3-dialkylimidazolium chloride aluminum-chloride ionic liquids. 2. phase-transitions, densities, electrical conductivities, and viscosities. J. Phys. Chem. 88, 2614-2621 (1984)... 

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. 

ILs can be classified into two main groups the first group contains simple salts with simple cation and anion, for example, ethylammonium nitrate, and the second group consists of binary systems, that is, mixtures of different ionic species, for instance, aluminum(III) chloride and 1,3-dialkylimidazolium chloride, where the melting point is dependent on the salt composition (Earle and Seddon, 2000). 

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