Tellurium tetrafluoride

Tellurium tetrafluoride, Tep4 m.p. 130 C. Colourless deliquescent solid prepared SeF4 plus TeOj. Hydrolysed by water. 

Tellurium Tetrafluoride. TeUurium tetrafluoride [15192-26-4] TeF, forms white, hygroscopic needles melting at 129.6°C. It decomposes at 194°C to TeFg and is readily hydrolyzed. Tellurium tetrafluoride attacks glass, sUica, and copper at 200°C, but it does not attack platinum below 300°C. 

Although free from the formally oxidising anions present in the two groups below, a few of these compounds show instability. These are m-Bis(trimcthvlsilylamino )tellurium tetrafluoride, 2615 Pentaamminechlororuthenium chloride, 4137... 

Tellurium Tetrafluoride, TeF4, is formed by the action of fluorine on tellurium, the heat of the reaction causing the mass to become incandescent.3... 

Tellurium tetrafluoride is a deliquescent solid which is decomposed... 

Tellurium tetrafluoride combines with the fluorides of the alkali metals (including ammonium) and barium fluoride, producing colourless crystalline salts of the general formula XF.TeF4, in which X represents the equivalent weight of the metal.2... 

Tellurium Hexafluoride, TeFe, appears to be more stable than tellurium tetrafluoride. It has been obtained by the action of fluorine on tellurium at —78° C. The resulting colourless crystalline solid vaporises on allowing the temperature to rise. The solidified substance melts at —36° C. and boils at —35-5° C., the critical temperature being 83° C. The vapour density is 119-5, agreeing with the formula TeFe. The gas has an unpleasant odour, recalling ozone and tellurium hydride. Water only slowly decomposes the gas, which does not attack glass. 

Tellurium tetrafluoride and dialkyltrimethylsilylamines, when refluxed in benzene until the evolution of fluorotrimethylsilane had ceased, produced bis[dialkylamino tellurium difluorides2. The reaction cannot be stopped at the dialkylamino tellurium trifluoride stage. 

Bis[morpholino] Tellnrium Difluoride2 7.1 g (35 mmol) of tellurium tetrafluoride are suspended in 50 ml of... 

Tellurium tetrafluoride and tellurium tetrachloride reacted exothermically with N,N-bis[trimethylsilyl]acetamide and with Ar,A -bis[trimethylsilyl]arcnesulfonamides in benzene to precipitate the corresponding diimino tellurium compounds2. 

Bis[acetylimino] Tellurium2 5.1 g (25 mmol) of tellurium tetrafluoride dissolved in 100 ml of benzene are added to a stirred solution of 10.6 g (52 mmol) of bis[trimethylsilyl]acetamide in 40 ml of benzene. When the exothermic reaction has subsided, the mixture is stirred for 6 h at 20", kept overnight at 20°, and filtered. The solid is washed with diethyl ether and dried under reduced pressure yield 4.7 g (77%) m.p. 152°. 

Reaction of tellurium tetrafluoride or tellurium tetrachloride with A7,Ar-bis[trimcthyl-silyl]acetamide or -arenesulfonamide in benzene, produced imino tellurium dihalides2. 

Acetylimino Tellurium Difluoride1 2.0 g (10 mmol) of tellurium tetrafluoride and 40 ml of benzene are vigorously stirred and a solution of 2.0 g (10 mmol) of /V.yV-bisftrimethylsilyl]acct amide in 20 ml of benzene is added dropwise. Stirring is continued at 20° for 5 h, the mixture is then filtered, the solid is washed several times with diethyl ether, and dried. The product should be stored with protection from moisture yield 2.1 g (96%) m.p. 113°. 

Heating tellurium tetrafluoride with an excess of fluoroalkoxytrimethylsilaneat 100 to 120° until the evolution of fluorotrimethylsilane ceases, produced tellurium tetrakis[fluoro-alkoxides]10. 

Tellurium Tetrakisifluoroalkoxide]1 30 mmol of tellurium tetrafluoride are mixed with 150 mmol of fluoroalkoxytrimethylsilane and the mixture is heated at 100-120° until evolution of fluorotrimethylsilane has stopped. The mixture is filtered and the filtrate is distilled under reduced pressure. 

After tellurium tetrafluoride and fluoroalkoxytrimethylsilane (molar ratio 1 3) were refluxed in benzene for four hours, the corresponding tris[fluoroalkoxy] tellurium fluoride was isolated and purified by vacuum distillation2. 

The same compounds were obtained when tellurium tetrafluoride and three molar equivalents of tellurium tetrakis[fluoroalkoxides] were refluxed in benzene3. 

Heating tellurium tetrafluoride and fluoroalkoxytrimethylsilane (1 2 molar ratio) in benzene for 2h produced bis[fluoroalkoxy] tellurium difluorides in high yields1. 

The same compounds were obtained by refluxing equimolar amounts of tellurium tetrafluoride and tellurium tetrakis[fluoroalkoxides] in benzene1. 

Bis[2,2,3,3-telrafluoropropoxy] Tellurium Difluoride1 6.1 g (30 mmol) of tellurium tetrafluoride are suspended in 50 ml of anhydrous benzene, 12.2 g (60 mmol) of 2,2,3,3-tetrafluoro-l-trimethylsiloxypropane are added dropwise with stirring, the mixture is heated at 70° for 2 h, and filtered. Fluorotrimethylsilane and benzene are distilled from the filtrate and the residue is distilled under vacuum yield 11.1 g (87%) b.p. 95o/0.03 torr. 

When equimolar amounts of fluoroalkoxy tellurium trifluorides and fluoroalkoxytrimeth-ylsilanes were heated in benzene at 70° for two hours and the reaction mixtures worked up as described for the reactions between tellurium tetrafluoride and fluoroalkoxy trimeth-ylsilanes, bis[fluoroalkoxy] tellurium difluorides were obtained1. 

Equimolar amounts of tellurium tetrafluoride and fluoroalkoxytrimethylsilane reacted in benzene at 60° to give fluoroalkoxy tellurium trifluorides2. 

Tellurium tetrakis[fluoroalkoxides] and three molar equivalents of tellurium tetrafluoride in refluxing benzene produced fluoroalkoxy tellurium trifluorides1. 

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