Lithium bromide chloride

Lithium bromide,-chloride, 10% 20 B 20 B Stress crack formation in saturated solutions... 

The first reported synthesis of acrylonitrile [107-13-1] (qv) and polyacrylonitrile [25014-41-9] (PAN) was in 1894. The polymer received Htde attention for a number of years, until shortly before World War II, because there were no known solvents and the polymer decomposes before reaching its melting point. The first breakthrough in developing solvents for PAN occurred at I. G. Farbenindustrie where fibers made from the polymer were dissolved in aqueous solutions of quaternary ammonium compounds, such as ben2ylpyridinium chloride, or of metal salts, such as lithium bromide, sodium thiocyanate, and aluminum perchlorate. Early interest in acrylonitrile polymers (qv), however, was based primarily on its use in synthetic mbber (see Elastomers, synthetic). 

Diphenylimidazole with palladium acetate forms the cyclometallated complex 80 (X = OAc) (97AOC491). The acetate group is replaced by chloride or bromide when 80 (X = OAc) reacts with sodium chloride or lithium bromide, respectively, to give 80 (X = C1, Br). Bromide with diethyl sulfide forms the mononuclear complex 81. Similar reactions are known for 1 -acetyl-2-phenylimidazole (96JOM(522)97). 1,5-Bis(A -methylimidazol-2-yl)pen-tane with palladium(II) acetate gives the cyclometallated complex 82 (OOJOM (607)194). 

Metal halide salts other than sodium iodide have been used sparsely to prepare halodeoxy sugars from sulfonate esters. Lithium chloride (107) and lithium bromide (33) have found limited application. Potassium fluoride (dihydrate) in absolute methanol has been used (51, 52) to introduce fluorine atoms in terminal positions of various D-glucose derivatives. The reaction is conducted in sealed tube systems and requires... 

Beckmann, J., and W. Albers, 1996. Air Conditioning and Dehumidification by a Lithium Bromide/Lithium Chloride Liquid Desiccant Technology, InAb-Sorption96 International Ab-Sorption Heat Pump Conference, Natural Resources Canada, Quebec, Canada, pp. 697-702. 

The method is similar to that for the chloride except that lithium bromide is added to the preparation. 

To a solution of 2 g. of rhodium(III) chloride trihydrate in 70 ml. of ethanol is added 12 g. of triphenylphosphine in 250 ml. of hot ethanol. After refluxing until the red solution begins to lighten in color (about 5 minutes), 8 g. of lithium bromide dissolved in 50 ml. of hot ethanol is added and the mixture refluxed for an hour. The orange prisms of the complex are collected by filtration, washed with 50 ml. of anhydrous ether, and dried in vacuum yield 5.1 g. (64% based on rhodium). 

Another variation of this method involves the treatment of an acetonitrile solution of the aryl aldehyde, trimethylsilyl chloride, and either sodium iodide, if iodide products are desired, or lithium bromide, if bromide products are desired, with TMDO. After an appropriate reaction time (5-195 minutes) at a temperature in the range of —70° to 80°, the upper siloxane layer is removed and the benzyl iodide or bromide product is isolated from the remaining lower portion after precipitation of the inorganic salts by addition of dichloromethane. For example, p-anisaldehyde reacts to form /i-rnethoxybenzyl bromide in 84% isolated yield under these conditions (Eq. 200).314,356... 

Bromobenzotellurophene ° A mixture of 2.0 g (19.6 mmol) of phenylacetylene, 1.0 g (6.3 mmol) of tellurium dioxide, 2.0 g (23 mmol) of lithium bromide aud 50 uiL of acetic acid is heated uuder reflux for 20 h, cooled to 20°C, aud poured iuto 150 uiL of diethyl ether. Aqueous sodium hydrogeu carbouate solutiou (5%) is added uutil all the acid has beeu ueutralized. The orgauic phase is separated, dried with auhydrous calcium chloride, fdtered aud evaporated. The browu, oily residue is dissolved iu a mixture of 30 mL of carbou tetrachloride aud 10 mL of petroleum ether (b.p. 30 0°C). Chloriue is carefully bubbled through this solutiou uutil precipitatiou of the product ceases. The yellow precipitate is filtered and recrystallized from acetonitrile. Yield 2.2 g (92%) m.p. 263-265°C. 

Lithium bromide also combines with gaseous ammonia to form four solid deliquescent substances. The monammine, [Li(NH3)]Br, is formed above 95° C. the diammine, [Li(NIi3)2]Br, between 87° and 95° C. the triammine, [Li(NH3)3]Br, between 71° and 87° C. and the tetrammine about —18° C.2 Ephraim prepared other ammino-salts of lithium, as, for example, tetrammino-lithium nitrate, [Li(NH3)J(N03), which is a colourless syrup at ordinary temperature and is more stable than the chloride tetrammino-lithium chlorate, [Li(NII3)Ll]C103, which is a fairly mobile liquid and tetrammino-lithium perchlorate, [Li(NH3)4]C104, a white solid which liquefies and decomposes at ordinary temperature.3... 

The trapping of lithiohalocyclopropanes by carbon dioxide, aldehydes and acid chlorides, respectively, constitutes a useful route to the corresponding cyclopropanecarboxylic acids, alcohols and ketones. In the case of ketones an intramolecular loss of lithium bromide may take place yielding spiroepoxides which in turn may be isomerized to cyclobutanones. 

In order to obtain metallic lithium, A. Guntz electrolyzed a mixture of equal arts of lithium and potassium chlorides and 0. Ruff and 0. Johannsen obtained etter results with a mixture of lithium bromide with 10 to 15 per cent, of the chloride. The electrolysis is conducted in a graphite retort with a thick iron wire as cathode, and a current of 100 amps, at 10 volts gave an 80 per cent, yield. 

Aq. soln. of lithium chloride absorb larger amounts of ammonia than water alone, owing to the formation of complexes, LiCl(NH3) —lithium ammino-chlorides. Similar remarks apply to lithium bromide and iodide. If the solubility of ammonia in water be unity, R. Abegg and H. Riesenfeld found the solubility at 25° is ... 

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