Lithium bromide properties

The next step was to determine the influence of the reaction temperature and whether or not an excess of the reagents in the relative properties TEA TMSC1 LiBr = 1 1 2 should be used. A second response surface model was therefore established. It was found that running the reaction at 40 °C and using 1.5 equivalents of TMS and TEA respectively, and 3 equivalents of lithium bromide afforded 96.7 and 98.2% yield in duplicate runs. These results were assumed to reflect closely the optimum conditions and were used in preparative runs. 

Other investigations of the properties of aqueous solutions have been made by various experimenters.1 Bonnefoi2 has prepared complex compounds of lithium bromide and ammonia analogous to those formed by the chloride (p. 62). 

The properties of irans-RhCl(CO)(PPh3)2 (m.p. 195-197°) and /mns-RhCl(CO)(AsPh3)2 (m.p. 242-244°) have been given. The chlorides can be rapidly converted to the corresponding bromides, iodides, or thiocyanates by the interaction in acetone solutions at room temperature with lithium bromide, sodium iodide, or potassium thiocyanate, respectively. Alternatively, rhodium (III) chloride can first be converted to the bromide or iodide by boiling the ethanolic solution with a ca. fivefold excess of lithium bromide or iodide. 

Esterification of the ketoacid (39) with diazomethane afforded the ketoester (40). This, on treatment with sodium hydride and diethyl carbonate in 1,2-dimethoxyethane, furnished (41) whose NMR spectrum was rather complicated, probably due to contamination with a small amount of tautomer. Reduction of the free carbonyl group with sodium borohydride led to the formation of alcohol whose tosyl derivative on heating with lithium bromide and lithium carbonate in dimethylformamide gave the diester (42). Its spectroscopic properties were identical with those of the one reported [20]. As the diester (42) has already been converted to warburganal (12), the present route for the diester (42) constitutes a formal total synthesis of warburganal. 

Deanin and Dossi used the propylene oxide-MA reaction to prepare cured polyester resin products in a one-step procedure. In the method explored, the epoxide, MA, phthalic anhydride, styrene, lithium bromide, and benzoyl peroxide were combined, heated to a melt, and cured as castings. The properties of the cured materials were inferior to conventional systems. Others have also studied this concept.A one-step (condensation-addition) polymerization procedure has also been studied as a method for preparing coatings " and laminates with epoxy resins. 

Lithium Bromide 10 15-35 5 Limited resistance noticible change in properties a prolonged time of exposure might cause irreversible damage (polymer degradation) ... 

Lithium Bromide (cont) solution aqueous 10 15-35 9 Resistant only slight changes to weight dimensions properties according to current knowledge the medium causes no irreversible damage to the polymer Ultradur B4250 BASF... 

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