Tellurium tetrabromide

Tellurium Tetrabromide. Tellurium tetrabromide [10031-27-3] TeBr, forms yellow hygroscopic crystals which decompose above 280°C and melt at 363°C under bromine vapor. It boils at 414—427°C, dissociating into TeBr2 and bromine. It is soluble in ether and chloroform but not in CCl, and is readily hydroly2ed in water. 

With the exception of the reactions of trifluoromethyl radicals with sulfur vapor, which is really a separate class of reactions, if the power supplied to the load coil surrounding the reactor (see Fig. 2) was maintained at, or near, the minimum amount needed to support the discharge, in only two cases were compounds found that clearly resulted from reactions other than replacement of halogen by trifluoromethyl. The reaction of tellurium tetrabromide (or the chloride) gave, in addition to the products just reported, very small proportions of such species as BrCF2TeCF2Br and (C2F5)2Te, which were isolated in yields of... 

See Tellurium tetrabromide Ammonia Tellurium tetrachloride Ammonia... 

Silver difluoride, 0014 Silver fluoride, 0013 Sodium chloride, 4036 Sodium iodide, 4623 Tantalum pentachloride, 4185 Tellurium tetrabromide, 0296 Thallium, 4922 Tin(II) chloride, 4116 Tin(IV) chloride, 4174 Tin(II) fluoride, 4331 Titanium(II) chloride, 4117 Titanium dibromide, 0284 Titanium diiodide, 4630 Titanium tetrachloride, 4176 Titanium tetraiodide, 4638 Titanium trichloride, 4158... 

Tellurium tetrachloride (as well as tellurium tetrabromide and tellurium tetraiodide) reacts with 4 mol equiv of arylmagnesium bromide, giving rise to diaryl teUurides in high yields. ... 

The aryl derivatives, which are not easily accessible from tellurium tetrabromide and tetraiodide, are therefore prepared by this route. 

With chlorine and bromine, products are tellurium tetrachloride, TeCL, a white, very hygroscopic crystalline solid, and tellurium tetrabromide, TeBr4, an orange crystalline solid ... 

Tellurium tetrabromide is amphoteric in fused arsenic tribromide, from which complex bromides such as [(Et)4N]2TeBr6 and ammine adducts such as TeBr4-2PhNMe2 have been obtained. Addition compounds with pyridine, tetramethylthiourea and piperazine have also been reported.38,39 Alkali metal Salts such as TeBr4-2CsCl and the full brominated complexes of the type M2TeBr6 and M2PoBrs are also known. 

Brauner, after trying various unsatisfactory methods, prepared and analysed pure tellurium tetrabromide,7 obtaining the value 127-54. 

Tellurium Dibromide, TeBr2.—Just as the tetrachloride can be reduced to the dichloride, so can tellurium tetrabromide be made to yield the dibromide by treatment in dry ether solution in the dark with finely divided tellurium. The solution so obtained is chocolate-brown in colour and is decomposed by water 8... 

Tellurium Tetrabromide, TeBr4.—This compound can be produced by the action of excess of bromine on tellurium, the vigour of the reaction being moderated by cooling. The excess of bromine is subsequently removed by evaporation. There is a danger of the product containing a little of the dibromide or a little unaltered tellurium it may therefore be purified by fractional sublimation under reduced... 

Tellurium tetrabromide is slightly hygroscopic and can be dissolved in a little water without decomposition. The aqueous solution, on evaporation over sulphuric acid, yields a deep red hydrated product. More water causes hydrolysis to tellurous and hydrobromic acids ... 

On this decomposition depends the effectiveness of the suggested method for freeing crude tellurium tetrabromide from any oxybromide present in it. 

Tellurium Dicyanide, Te(CN)a.—Tellurium tetrabromide and silver cyanide in a suitable organic solvent such as benzene react according to the equation... 

Tellurium and Bromine. —Tellurium Dibromidn, Tellurium Tetrabromide, Tellurium Oxybromides. 

Tellurium tetrachloride and tellurium tetrabromide reacted with four molar equivalents of dithiocarboxylic acids or their piperidinium salts. Tellurium bis[dithiocarboxylates] were formed1. However, the reaction between tellurapentathionate and dithiocarboxylates is the preferred method for the preparation of tellurium bis[dithiocarboxylates] ... 

Tellurium tetrachloride and tellurium tetrabromide were converted to tellurium dithiocarboxylate halides in reactions with two or fewer molar equivalents of dithiocarboxylic acids1,2 or their piperidinium salts1. Reactions with a 3 1 molar ratio of the reagents (dithiocarboxylate/tellurium tetrahalide) were not carried out. 

The reactions with tellurium tetrabromide were carried out at 0°. 

Solutions of sodium fluoroalkoxides in diethyl ether reacted with suspensions of tellurium tetrachloride or tellurium tetrabromide in ethanol at room temperature to produce the... 

Tris fluoroalkoxy tellurium bromides were synthesized by refluxing a mixture of three moles of tellurium tetrakis[fluoroalkoxides] and one mole of tellurium tetrabromide in benzene. The oily products were isolated by removal of the solvent in vacuo1. 

When equimolar amounts of tellurium tetrabromide and sodium dimethyldithiocarbamate were combined in dioxane, bromobis[dimethyldithiocarbamato]tellurium tetrabromo(di-... 

From Tellurium or Tellurium Tetrabromide and Organic Radicals... 

The compound decomposed on storage with deposition of tellurium1. Tellurium tetrachloride need not be used in substance it can be generated in the reaction mixture from tellurium dioxide and acetyl chloride or chlorotrimethylsilanc. With acetyl bromid tellurium tetrabromide can be formed. When cyclohexene was present in the reaction mixture, 2-halocyclohexyl tellurium trihalides were isolated in approximately 70% yields. Acetic acid, chloroform, or dichloromethane may be used as solvents2. 

When the addition reactions of tellurium tetrachloride or tellurium tetrabromide were carried out in the presence of an alcohol with a cycloalkene as the olefin, trans-2-alkoxycycloalkyl tellurium trihalides were isolated in yields ranging from 30 to 80%4... 

The reaction between tellurium tetrabromide and cycloheptene with ethanol as the solvent yielded 2-ethoxycycloheptyl tellurium tribromide2. The 2-bromocycloheptyl tellurium tribromide, a likely intermediate, could have reacted with ethanol. 

Tellurium dicyanide was prepared from tellurium tetrabromide and silver cyanide (Vol. IX, p. 932). Tellurium dicyanide, which was found to be quite stable in acetonitrile solution, reacted with excess cyanide ion to form tricyanotellurate(II) as an unstable intermediate3. 

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