From Sodium Arenetellurolates and Arylseleno bromomethanes

Arylselenomethyl aryl telluriums are obtained from sodium arenetellurolates and (arylseleno)bromomethanes. The tellurolates are generated by the reduction of diaryl ditelluriums with sodium borohydride.  

Phenyl Phenylselenomethyl Tellurium 2.05 g (5 mmol) of diphenyl ditellurium are dissolved in dml of ethanol/benzene (3/1, v/v) and the solution is placed in a nitrogen-flushed, 250-ml flask equipped with a magnetic stirrer. 10 g (265 mmol) of sodium borohydride are dissolved in 200 w/ of 1 M aqueous sodium hydroxide solution. The sodium borohydride solution is added dropwise at 20° to the stirred diphenyl ditellurim solution until the mixture becomes colorless. Then 2.5 g (10 mmol) of phenylselenobromometh-ane are added immediately and the mixture is stirred at 20° for 30 min. 10 m/of dichloromcthane are added, the organic layer is separated, washed successively with saturated ammonium chloride solution and brine, and dried with anhydrous magnesium sulfate. The dried extract is filtered and the filtrate evaporated. The residue is dissolved in petroleum ether (b.p. 30-60°), and the solution is cooled to — 78° whereupon the product crystallizes yield 2.5 g (66%) m.p. 51°. 

Similarly prepared were 4-chlorophenylselenomethyl phenyl tellurium 4-methoxyphenyl 4-methoxyphenylselenomethyl tellurium  

4-ethoxyphenyl phenylselenomethyl tellurium 4-methoxyphenylselenomethyl 2-naphthyl tellurium  

The crude products were always obtained in quantitative yields. Purification of the air-sensitive compounds led to lowered yields. 

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