Telluronium Hydroxide

Triorgano telluronium halides are converted to triorgano telluronium hydroxides upon shaking with an aqueous suspension of silver oxide3 6. In most instances, the triorgano telluronium hydroxide is not isolated but reacted with an acid such as hydrofluoric acid or picric acid to produce telluronium salts with an acid-derived anion. 

Examples of similarly prepared triorgano telluronium hydroxides are ... 

Neutralization of a trimethyl telluronium hydroxide solution to methyl red with hexafluorosilicic acid followed by evaporation of the solution to dryness on a steam produced bis[trimethyl telluronium] hexafluorosilicate (decomposes at 320-336°, from ethanol)1. 

Alkoxycarbonylmethyl diphenyl telluronium bromides shaken with an aqueous suspension of silver oxide for 3 days produced carboxymethyl diphenyl telluronium hydroxides. 

Bis[2,2 -biphenyldiyl tellurium was similarly obtained in 36% yield. Because this compound is not as easily converted by water to the telluronium hydroxide as tetraphenyl tellurium is converted, the reaction mixture is poured into ice/water and the precipitated solid recrystallized from acetone2. 

Tetramethoxy tellurium and 2,2 -dilithiobiphenyl combine, to give 2,2 -biphenyldiyl 2-biphenylyl telluronium hydroxide as, by-product12. 

Carboxymethyl Diphenyl Telluronium Hydroxide 5.0 g (12 mmol) of carboxymethyl diphenyl telluronium bromide and 2.0 g (8.6 mmol) of silver oxide in 45 ml of water are shaken for 4 days. The mixture is filtered, the filtrate is concentrated under vacuum at 20°, and the crystals are collected m.p. 118°. 

Triorgano telluronium hydroxides, obtained by treating triorgano telluronium halides with an aqueous suspension of silver oxide, react with acids such as hydrohalic acids , hexafluorosilicic acid , picric acid and with alkali metal halides The telluronium hydroxides are generally not isolated. 

Biphenyldiyl 2-Biphenylyl Telluronium Hydroxide A solution of 66.4 mmol of 2,2 -dilithiobiphenyl in 250 ml of dry diethyl ether is prepared under nitrogen and cooled to — 70°. A solution of 8.17 g (32.5 mmol) of tetramethoxy tellurium in 300 of diethyl ether is added dropwise, the mixture is allowed to warm to 20°,... 

Ethoxyphcnyl Tetramethylene Telluronium Bromide1 A solution of 3.08 g (6.2 mmol) of bis[4-ethoxyphenyl] ditellurium in a mixture of 2.5 ml of benzene and 7.5 ml of ethanol is heated under reflux. 0.04 g (10 mmol) of sodium borohydride dissolved in 8.5 ml of 1 molar aqueous sodium hydroxide solution followed by 0.22 g (1 mmol) of 1,4-dibromobutane dissolved in 5 ml of benzene are added dropwise to the refluxing solution. The warm mixture is stirred for 30 min, filtered, the solid is washed with diethyl ether, and dried under vacuum yield 0.30 g (80%) m.p. 280° (from acetonitrile). 

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