Aryl Tellurium Dichloride Amides

4-Methoxyphenyl Tellurium [0,0 -Dimethyl dithiophosphate] Dibromide Dry ammonium 0,0 -dimethyl dithiophosphate (42 mg, 0.22 mmol) is added to a slurry stirred solution of 103 mg (0.22 mmol) of 4-methoxyphenyl tellurium tribromide in 5 ml carbon disulfide. The mixture is stirred at 20° for 0.5 h and then filtered. The solvent is evaporated from the filtrate at 0° under reduced pressure. The gummy yellow residue is recrystallized from chloroform/hexane (1 1) at — 4 . The crystals are collected and dried under reduced pressure yield 74% m.p. 121°. 

4-methoxyphenyl tellurium[0,0 -diethyl dithiophosphate] dichloride yield 49% m.p. 97° 

Ary] tellurium dichloride amides are highly air- and moisture-sensitive. They decompose slowly over a period of three weeks when stored under an inert atmosphere at 20°. Hydrazine in ethanol reduces these compounds to the corresponding diaryl ditelluriums.  

Aryl tellurium trichlorides react vigorously with trimethyl(dialkylamino)silanes in benzene under an atmosphere of dry nitrogen.  

Phenyl Tellurium Dichloride Diethylamide A system consisting of a 200 ml round bottom flask, a reflux condenser, a dropping funnel, and a magnetic stirrer is flushed with dry nitrogen, the flask is flame-dried, and charged with 50 m/ of anhydrous benzene and 3.1 g (10 mmol) of phenyl tellurium trichloride. 1.5 g (10 mmol) of trimethyl(diethylamino)silane are added dropwise to the stirred benzene solution, stirring is continued for 3 h, and the mixture is filtered in a Schlenk-type apparatus. 50 ml of petroleum ether (b.p. 30-60°) are added to the filtrate, the resultant slurry is allowed to settle 3 h, the clear supernatant liquid is decanted, petroleum ether is added to the decantate, and the solution is allowed to stand overnight. The yellow crystals are filtered and dried under vacuum yield 1.3 g (31%) m.p. 105° (dichloromethane-/petroleum ether). 

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