Lithium iodide dihydrate

By using three mole equivalents of lithium iodide dihydrate, at the end of 6.5 hours of reflux a 77% yield of 2-benzylcyclopentanone is obtained. 

Esters Lithium iodide. Lithium iodide dihydrate. Methanesulfonic acid. 

Lithium iodide dihydrate, LiL2 H2O. Mol. wt. 169.88. Supplier Fluka. 

Whereas anhydrous lithium iodide in a refluxing base of suitable boiling point cleaves esters to the corresponding acids, lithium iodide dihydrate effects cleavage and concomitant decarboxylation, as illustrated for the case of 2-benzyl-2-carbo-methoxycyclopentanone. Elsinger refluxed a mixture of this keto ester, lithium... 

Decarboxylation Benzoic anhydride. N-Bromosuccinimide. r-Butylhydroperoxide. r-Butyl-hypoiodite. Copper chromate. Copper powder. Copper salts. Cuprie carbonate. N,N-Di-methylanilrne. N,N-Dimethyl-p-toluidine see Potassium permanganate, reference 32). Lead dioxide. Lead tetraacetate. Lithium iodide dihydrate. Potassium fluoride. Quinoline. Sodium hypochlorite. 

Lithium iodide dihydrate is available from Fluka A.G., Buchs, S.G., Switzerland. The checkers used the trihydrate and, by means of a Dean Stark trap 4 attached between the flask and the condenser, 1 mole, of water was removed via azeotropic distillation with collidine. 

A soln. of 2-benzyl-2-carbomethoxycyclopentanone in 2,4,6-collidine added to a refluxing soln. of lithium iodide dihydrate in the same solvent, and refluxed 19 hrs. under Ng 2-benzylcyclopentanone. Y 72-76%, Also preferential de-carbomethoxylation s. F. Elsinger, Org. Synth. 45, 7 (1965). 

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. 

Lithium iodide, Lil.—On evaporation of the solution obtained by the interaction of lithium carbonate and hydriodic acid, or barium or calcium iodide, lithium iodide crystallizes in the form of hydrates,7 a trihydrate, dihydrate, and monohydrate having been isolated. Above 300° C. the anhydrous salt is formed, but its action on glass and porcelain at high temperatures has prevented its preparation in the pure state. The boiling-point of the iodide is 1170° C.,8 and the vapour-pressure in atmospheres corresponds with the expression... 

The hydrate system formed by lithium iodide will be used to illustrate the stepwise dehydration process. When heated at temperature values below the melting point of anhydrous lithium iodide (446°C), the trihydrate is capable of losing its water of hydration to form a dihydrate and a monohydrate on the way to the anhydrate phase ... 

Vapor pressure of water over the trihydrate, dihydrate, and monohydrate phases of lithium iodide as a function of temperatme. (The data were plotted from published values from... 

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... 

Iron(II) fluoride Iron(II) hydroxide Iron(III) hydroxide Iron(III) phosphate dihydrate Lanthanum iodate Lead(II) bromide Lead(II) carbonate Lead(II) chloride Lead(II) fluoride Lead(II) hydroxide Lead(II) iodate Lead(II) iodide Lead(II) selenate Lead(II) sulfate Lithium carbonate Lithium fluoride Lithium phosphate Magnesium carbonate Magnesium carbonate trihydrate... 

Sodium dichromate dihydrate 7789-17-5 Cesium iodide 7789-18-6 Cesium nitrate 7789-21-1 Fluorosulfonic acid 7789-23-3 Potassium fluoride 7789-24-4 Lithium fluoride 7789-25-5 Nitrosyl fluoride 7789-29-9 Potassium bifluoride 7789-36-8 Magnesium borate 7789-38-0 Dyetone ... 

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