From Hydroxy Tellurium Pentafluoride

Imidazolinium pentafluoro(oxo)tellurate (VI), methanol, and excess imidazole gave imidazolinium c 5-methoxo(tetrafluoro)oxotellurate(VI), which was converted to cis-hydroxy methoxy tellurium tetrafluoride on treatment with 96% sulfuric acid.  

Irgolic Organo-tellurium Compounds without a C,Te-Bond 

Cis- and ranj-hydroxy methoxy tellurium tetrafluoride reacted stereospecifically with chlorotrimethylsilane tetramethylstannane, and boron trichloride with elimination of hydrogen chloride or methane. The compounds obtained are trimethylsiloxy methoxy tellurium tetrafluoride trimethylstannoxy methoxy tellurium tetrafluoride, and boron tris[methoxo(oxo)tetrafluorotellurate (VI)] 

The HjC-O-Te bonds are remarkably stable no cis-trans isomerization was observed when the hydroxy methoxy tellurium tetrafluorides were kept at temperatures below 130°. The bonds are not cleaved by 65% oleum or chlorosulfonic acid at room temperature, instead, the sulfate esters HjCO-TeF tO-SOjH) were formed. These sulfate esters were transformed to HO-TeFiCO-SOjH) upon heating to 100°. Cesium chloride dissolved in an excess of cis- or /run.s-hydroxy methoxy tellurium tetrafluoride liberated hydrogen chloride with the formation of very hygroscopic cesium methoxo(oxo)letrafluorotellurates(VI). Trunj-hydroxy methoxy tellurium tetrafluoride reacts instantaneously with water with loss of fluoride. The cu-compound is stable toward hydrolysis at room temperature.  

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