With Dihydrogen Peroxide and a Carboxylic Acid

A convenient single-step method for the preparation of diaryl tellurium dicarboxylates in 82 to 92% yields involves the reactions of the diaryl tellurium with hydrogen peroxide and carboxylic acids . The reaction probably proceeds via diaryl tellurium oxides as intermediates. Carboxylic acid anhydrides can be used instead of the carboxylic acids. 

Diphenyl Tellurium Diacetate 2.8 g (10 mmol) of diphenyl tellurium are dissolved in 20 ml of chloroform and 1.5 g (25 mmol) of glacial acetic acid and 5 mg of triethylbenzyl ammonium chloride are added. 1.7 w/of 25 % hydrogen peroxide are then added dropwise to the stirred mixture. The organic layer is separated, dried, the chloroform is evaporated, and the residue is washed with a mixture of hexane and diethyl ether yield 3.6 g (90%) m.p. 138°. 

Similarly prepared was dibenzo-1,4-oxatellurin 10,10-diacetate (yield 90% m.p. 207°). 

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