1-butylpyridinium chloroaluminate

FAB MS has been applied in a number of studies to characterize ILs. Since most ILs are viscous liquids with negligible vapor pressure, the measurement of FAB MS is possible without the addition of a liquid matrix. In principle, ILs can therefore also be used as matrix substances for the FAB analysis of other analytes dissolved therein [12]. Spectra could be measured both in the positive and in the negative ion modes as has been demonstrated, for example, for butylpyridinium- chloroaluminates and gallates [12,13]. Beside the molecular ions, fragments mainly formed by the loss of the substituents of the central core of the cations, for example, butyl groups, were observed. Together with the isotope patterns, these fragments provide valuable information about the structure of newly composed compounds and help also to identify unexpected by-products like oxidized or hydrolyzed compounds in the ILs (see section 14.3.2). 

This catalyst is n-butylpyridinium chloroaluminate, see Rebeiro, G.L. Khadilkar, B.M. Synth. Common. 2000, 30, 1605. 

Matsumoto, T. and Ichikawa, K., Determination of the Wl spin-lattice relaxation rate and the relative number of each chloroaluminate species in the molten 1-n-butylpyridinium chloride AlClj system, /. Am. Chem. Soc., 106, 4316, 1984. 

In 1980 Singh et al. reported the first example of a photoelectrochemical cell using an RTIL. They employed a chloroaluminate melt based on the A -butylpyridinium cation, denoted as BP, as a solvent and III-V semiconductors, namely n-GaAs [9-12] or n-InP [13], as the photoanode. Ferrocene and ferricinium chloride were used as the redox couple. The chloroaluminate-based RTIL used here was prepared by mixing equimolar amounts of AICI3 and BP-Cl. The viscosity of the RTIL is 21 mPas at 25°C [14]. 

The room-temperature chloroaluminate(lll) ionic liquids are the most important members of the first generation of ionic liquids, developed in the second half of the last century The room-temperature halogenoaluminate(III) ionic liquids are extremely sensitive to moisture and must be handled imder an inert atmosphere. Preparation of the halogcno-aluminate(III) ionic liquids is simple a quaternary ammonium (QUAT) halide, e.g. an imidazolium or pyridinium halide, is directly mixed with AICI3 in the ratio necessary to generate the composition required. Upon mixing, an exothermic reaction occurs and the two solids melt into a liquid. The first report on the formation of a room temperature liquid salt, based on the combination of 1-butylpyridinium with AICI3 in the relative molar proportions 1 2 (X =... 

As well as imidazolium based ionic liquids, other kinds of ionic liquids have also been developed for the MBH reaction. Kumar et al. have found that ionic liquid chloroaluminates, consisting of AICI3 and A-l-butylpyridinium chloride... 

Lewis acid-containing ionic liquids such as 1-butyl-3-methylimida-zolium (bmim) chloroaluminate, butylpyridinium chloro-aluminate, and FeCls-doped l-butyl-3-methylimidazolium triflimide have likewise proven effective promoters for the Pechmann condensation. [Bmim]Cl 2AlCl3 has proven to be one of the most reactive ionic liquid promoters, effecting the Pechmann condensation of ethyl acetoacetate and a range of electron-rich phenols in 10—45 min at 30 °C. ... 

Koura et al. [734] studied an interesting non-Li battery configuration using room-temperature melt chloroaluminate electrolytes, AlCls-l-butylpyridinium-Cl (BPC) or AlCl3-l-Et-3-Me-imidazolium-Cl (EMIC), with an Al/P(ANi)Cl-powder cathode and anode (Fig. 15-7). The optimum open circuit (initial discharge) potential was 1.6 V, the specific capacity 68 mAh/g-(P(ANi)), and claimed coulombic efficiency 99%. 

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