Lithium aryl tellurolates

The direct oxidation of lithium aryl tellurolates into the ditellurides without previous aqueous work-up is exemplified by the preparation of di(2,4,6-tri-t-butylphenyl) ditel-luride. ... 

Sodium benzenetellurolate is arylated in liquid ammonia via photoinduced reactions with aryl halides3,4. Aryl iodides reacted with sodium benzenetellurolate in the presence of copper(I) iodide in hexamethylphosphoric triamide (but not in DMF or DMSO) to produce aryl phenyl tellurium compounds5- However, lithium benzenetellurate reacted with 1,2-bromoiodobenzene and lithium methane tellurolate with 1,2-dibromobenzene in tetrahydrofuran at 20° to yield l,2-bis[organotelluro]benzenes6. 

The preparation of an aryl lithium compound from an aryl halide and an alkyl lithium compound also produces an alkyl halide. The alkyl halide may react subsequently with the lithium arenetellurolate to yield aryl alkyl tellurium compounds. In these cases the tellurolate has only a transitory existence. 

Tellurolates, which are easily accessible through reduction of diorgano di telluriums, can be alkylated and arylated and added across carbon-carbon triple bonds. In addition, the weakness of the Te —Te bond in diorgano ditelluriums can be exploited to prepare unsymmetrical diorgano telluriums. Many reagents such as organic lithium compounds,... 

The reaction can be performed in different organic solvents. Currently ethanol seems to be the most common solvent. This method has been employed almost exclusively for the preparation of sodium alkyl-, alkenyl-, aryl-, and heteroaryl tellurolates. Metallic lithium and sodium can also be used for the reduction of diorganyl ditellurides. 

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