From Tellurium Hexafluorides

Primary monohydric and polyhydric alkanols reacted with tellurium hexafluoride to form alkoxy tellurium pentafluorides. Primary alkanols and equimolar amounts of tellurium hexafluoride in the presence of sodium fluoride or pyridine gave alkoxy tellurium pentafluorides in yields generally higher than 70%.  

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°. 

Cholesteryloxy tellurium perttqfluoride (m.p. 153°) was similarly prepared using 1,2-dimethoxyethane as the solvent. The compound was purified by column chromatography with benzene as the mobile phase.  

The reaction of 2-A -acetylaminoethanol with tellurium hexafluoride in acetonitrile produced an oxazolinium pentafluoro(oxo)tellurate(VI) from the intermediary 2-N-acetylaminoethoxy tellurium pentafluoride that underwent intramolecular alkylation.  

Alcohols other than methanol reacted only slowly with tellurium hexafluoride in the presence of sodium fluoride as the HF-acceptor. The reactions proceeded much faster with 0.5 mole of pyridine per mole of tellurium hexafluoride. Under these conditions, small quantities of dialkoxy tellurium tetrafluorides are also formed.  

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