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Lithium halide solubilities

Some prapargylic halides can be converted into haloallenes by treating them with copper[I) halide and lithium halide, preferably in THF as solvent. A catalytic amount of the copper salt, which forms a soluble complex with lithium halide, is... [Pg.154]

Lithium Halides. Lithium haHde stabiHty decreases with increasing atomic weight of the halogen atom. Hence, the solubiHty increases from the sparingly soluble Hthium fluoride to the very soluble bromide and iodide salts. The low melting points of Hthium haHdes are advantageous for fluxes in many appHcations. [Pg.225]

Lithium Iodide. Lithium iodide [10377-51 -2/, Lil, is the most difficult lithium halide to prepare and has few appHcations. Aqueous solutions of the salt can be prepared by carehil neutralization of hydroiodic acid with lithium carbonate or lithium hydroxide. Concentration of the aqueous solution leads successively to the trihydrate [7790-22-9] dihydrate [17023-25-5] and monohydrate [17023-24 ] which melt congmendy at 75, 79, and 130°C, respectively. The anhydrous salt can be obtained by carehil removal of water under vacuum, but because of the strong tendency to oxidize and eliminate iodine which occurs on heating the salt ia air, it is often prepared from reactions of lithium metal or lithium hydride with iodine ia organic solvents. The salt is extremely soluble ia water (62.6 wt % at 25°C) (59) and the solutions have extremely low vapor pressures (60). Lithium iodide is used as an electrolyte ia selected lithium battery appHcations, where it is formed in situ from reaction of lithium metal with iodine. It can also be a component of low melting molten salts and as a catalyst ia aldol condensations. [Pg.226]

The first family of the so-called anion receptors was aza-ethers that were based on cyclic or linear amides, where the nitrogen core was made electron-deficient by the perfluoroalkylsulfonyl substituents so that these amides would preferentially interact with the electron-rich anions through Coulombic attraction, contrary to how their unsubstituted counterparts would act. Two selected representatives from the aza-ether family are shown in Table 8. When used as additives in solutions of various lithium halides LiX in THF, these novel compounds were found to increase both the solubility and the ion conductivity of these solutions. For example, the ion conductivity of the LiCl/THF solution was 0.0016 mS cm while the LiCl/THF solution with one of the linear aza-ethers containing eight perfluoroalkylsulfonyl substituents n = 5 for the linear aza-ether shown in... [Pg.125]

Schlosser modification of Wittig reaction The presence of soluble metal salts such as lithium salts decreases the aVfrans-selectivity. The normal Wittig reaction of non-stabilized ylides with aldehydes gives Z-alkenes. The Schlosser modification of the Wittig reaction of non-stabilized ylides furnishes -alkenes. In the presence of lithium halides oxaphosphetanes can often be observed, but betaine-lithium halide adducts are also formed. If lithium salts are added to the equilibrium, oxaphosphetane formation and elimination of... [Pg.160]

Lithium bis(trimethylsilyl)amide is a colorless solid which is soluble in a variety of organic solvents suitable for reactive compounds such as organometallic substances or substituted metal amides. The compound melts at 71 to 72°. It is unstable in air and catches fire when compressed, but it is stable in an atmosphere of nitrogen. Reactions with a variety of nonmetallic halides give lithium halides and hexamethyldisilazyl derivatives. [Pg.21]

For example, the lithium halides have solubilities roughly in the reverse order LiBr > LiCl > Lil > LiF. The solubilities show a strong hard-hard interaction in LiF that overcomes the solvation of water, but the weaker hard-soft interactions of the other halides are not strong enough to prevent solvation and these halides are more soluble than LiF. Lil is out of order, probably because of the poor solvation of the very large iodide ion, but it is still about 100 times as soluble as LiF on a molecular basis. [Pg.181]

Solid complexes of defined stoichiometry have been prepared for all the lithium halides with HMPA. For LiBr, both [LiBr(HMPA)2] and [LiBr(HMPA)4] have been obtained as solids of defined m.p., but the 1 1 complex, the kinetically active species for epoxide rearrangement, has not been isolated. The rate of epoxide loss and solubility of LiBr increased proportionately with added solubilizer (HMPA), to a maximum rate at a 1 1 ratio of addend LiBr. Additional HMPA beyond this ratio caused the rate to decrease even though all the LiBr remained in solution. At an addend LiBr ratio of 2 1, the reaction effectively ceased. These observations allow the conclusions that [LiBr(HMPA)2] is more stable than the reactive 1 1 complex in benzene, and that only the latter is kinetically competent. [Pg.763]

The unusual properties of polytertiaryamine chelated lithium salts have been noted (6). The high solubility and conductivity of chelated lithium halides in benzene raise a number of important and interesting questions concerning the role of the aromatic solvent since these chelated... [Pg.123]

Some of the most profound lithium ion effects are observed in diethyl ether, benzene, or toluene, and the literature on Wittig reactions under these conditions contains a number of results that appear to be somewhat contradictory. The reason for this lack of consistency may be related to issues of lithium halide or betaine adduct solubility. Thus, Bergelson and Shemyakin et al. (5c, d) were able to show that ylide solutions prepared in benzene behaved differently if they were filtered to remove precipitated salts prior to use (compare Table 11, entries 3 and 4 entries 47 and 48). Later, it was shown that filtered toluene solutions of Ph3P=CHCH3 obtained from the phos-phonium bromide using butyllithium contain <0.1% bromide according to elemental analysis (18b). Therefore, the dramatic change in the alkene ratio... [Pg.53]

Mercury(I) halides have a similar trend, with Hg2p2 the most soluble and Hg2l2 the least soluble. However, LiF is by far the least soluble of the lithium halides its K p is 1.8 X 10 , but the other lithium halides are highly soluble in water. Similarly, Mgp2 and AIF3 are less soluble than the corresponding chlorides, bromides, and iodides. [Pg.201]

Depending on their specific compositions and the procedures by which they are produced, protein polymers may be soluble or insoluble in aqueous solution. The BetaSilk and ProNectin polymers are insoluble in water. Prom a lyophilized powder they can be dissolved in concentrated chaotropic solvents such as aqueous formic acid or lithium halide salt solutions. For example, SLP3 is soluble in 88% formic acid at 10 w t% or greater. If the formic acid is either diluted by addition of water or if its pH is neutralized, SLP3 will precipitate. SLPF is soluble in 4.5 M lithium perchlorate solution at 1 w t%. Once dissolved the solution can be diluted wadi water or phosphate buffer to 0.1 w t% or less. It will remain in solution temporarily depending on its concentration (O.OI wa% solution will precipitate in about 8 hours). [Pg.401]

This result correlates with the relative stabilities of the product and starting material, which favor the chloroalkane. However, this equilibrium may be driven in the reverse direction by a simple trick Whereas all of the lithium halides are soluble in acetone, solubility of the sodium hahdes decreases dramatically in the order Nal > NaBr > NaCl, the last being virtually insoluble in this solvent. Indeed, the reaction between Nal and a primary or secondary chloroalkane in acetone is completely driven to the side of the iodoalkane (the reverse of the reaction just shown) by the precipitation of NaCl ... [Pg.234]

These are halides formed by highly electropositive elements (for example those of Groups I and II, except for beryllium and lithium). They have ionic lattices, are non-volatile solids, and conduct when molten they are usually soluble in polar solvents in which they produce conducting solutions, indicating the presence of ions. [Pg.343]


See other pages where Lithium halide solubilities is mentioned: [Pg.225]    [Pg.225]    [Pg.220]    [Pg.127]    [Pg.602]    [Pg.168]    [Pg.143]    [Pg.29]    [Pg.168]    [Pg.602]    [Pg.11]    [Pg.10]    [Pg.168]    [Pg.287]    [Pg.178]    [Pg.312]    [Pg.207]    [Pg.207]    [Pg.16]    [Pg.237]    [Pg.18]    [Pg.137]    [Pg.153]    [Pg.377]    [Pg.1361]    [Pg.211]    [Pg.312]    [Pg.220]    [Pg.127]    [Pg.220]    [Pg.103]    [Pg.14]   
See also in sourсe #XX -- [ Pg.181 ]




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Halides lithium

Lithium solubilities

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