Arenetellurinyl Carboxylates

Arenetellurinic acids are reduced to diaryl ditellurium compounds by potassium disulfite or 4-methylbenzenesulfonyl hydrazide.  

Addition of dilute acetic acid to 4-ethoxybenzenetellurinic acid caused formation of the anhydride s. 

Only a few examples of arenetellurinyl carboxylates, the mixed anhydrides of tellurinic acids and carboxylic acids, are known. These eompounds were prepared by refluxing mixtures of arenetellurinic acid anhydrides with acetic or trifluoroacetic acid or their anhydrides in chloroform . Acetonitrile and 1,2-dichloroethane were also used as solvents. Benzenetellurinyl trifluoroacetate is described as a very hygroscopic, intractable oil. The arenetellurinyl acetates are solids with melting points of approximately 150°. 

Benzenetellurinyl Acetate To a suspension of 0.457 g (1.0 mmol) of benzenetellurinic anhydride in 10 m/ chloroform are added 0.112 g (1.1 mmol) of acetic anhydride under an atmosphere of nitrogen. The mixture is refluxed for 30 min. When all the solid has disappeared, the solution is concentrated under reduced pressure. The residue is recrystallized from benzene/hexane. The colorless, hygroscopic crystals melted at 150-152° in a sealed tube yield 100%. 

Irgolic Organic Tellurium Compounds with one Te,C Bond 

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The reactions of arenetellurinyl carboxylates for the transformation of organic molecules were explored. 

Carboxylic acids or carboxylic acid anhydrides react with arenetellurinic anhydrides in refluxing chloroform, in 1,2-dichloroethane, or in acetonitrile to give arenetellurinyl carboxylates. 

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