From Methoxy Tellurium Pentafluoride

Methoxy tellurium pentafluoride and sodium methoxide (molar ratio 1 8) in methanol in a sealed tube at 20° produced, after 18 hours, a mixture offac- and mer-trimethoxy tellurium trifluoride. The composition of the reaction mixture was ascertained by F-NMR spectroscopy. 

F F H3CO-Te-F HsCO OCHs + H3CO-Te-OCH3 1 H3CO  

Dialkoxy tellurium tetrafluorides may react in chloroform with an excess of alcohol in the presence of pyridine to form trialkoxy tellurium trifluorides. Whether or not these reactions produce trialkoxy tellurium trifluorides depends on the nature of the alkoxy groups in the dialkoxy tellurium tetrafluoride and only secondarily on the nature of the alkyl groups of the alcohol. 

CH2CH2-SCH3 CH2CH2-SCHj CH2CII2-SCH3 

CH2CH2-OC2H5 CHjCHj-OCiH CH2CH2-OC2H5 

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Methoxy Tellurium Pentafluoride 1.3 g (40 mmol) of methanol and 10 g (41 mmol) of tellurium hexafluoride are condensed at —196° in a 400 ml tube containing 10 g (0.24 mol) of sodium fluoride. The tube is sealed, and the mixture is warmed to 20° and kept at this temperature overnight. Volatile materials are distilled from the mixture under reduced pressure into a cooled trap. The material in the trap is distilled at atmospheric pressure to give the product yield 7.6 g (75%) b.p. 58°. 

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