From Aryl Tellurium Cyanide

Primary and secondary alcohols may serve as the source of alkyl groups in the preparation of aryl phenyl tellurium compounds. Phenyl tellurium cyanide, conveniently obtained from diphenyl ditellurium (p. 368), reacted smoothly with alcohols in dichloromethane in the presence of tributylphosphane. The alkyl phenyl telluriums were obtained in yields ranging from 32 to 78%. Triphenylphosphane or triethyl phosphite did not catalyze these reactions.  

R = CfiH,7, C11H23, CijHjs, C14H29, CigH33, (CH2)2 —C Hj, CH CH3) —C12H25 

Dodecyl Phenyl Tellurium In 2 ml of dichloromethane are dissolved 0.20 g (0.87 mmol) of phenyl tellurium cyanide and 0.10 g (0.54 mmol) of dodecanol. The solution is placed in a 50-ml, nitrogen-flushed flask containing a magnetic stirrer and 0.5ml tributylphosphane are added. The mixture is stirred at 20° for 0.5 h and then the solvent is evaporated. The residue is chromatographed on silica gel with hexane as the mobile phase yield 0.12 g (62%) yellowish oil. 

Phenyl tellurium cyanide and co-halo-a-aminocarboxylic acids were claimed to react to yield phenyl cu-amino-co-carboxyalkyl telluriums  

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Arenediazonium tetrafluoroborates react with potassium tellurocyanate in DMSO. The expected aryl tellurium cyanides are seldom stable enough to be isolable and are converted to diaryl ditellurium compounds. Only 2-nitrophenyl tellurium cyanide and 2,6-dimethyl-phenyl tellurium cyanide were obtained through chromatographic separation from the diaryl ditellurium compounds6. 

Diaryl tellurium compounds can be obtained in moderate yields from potassium tellurocyanate and arenediazonium tetrafluoroborates in DMSO at room temperature. The potassium tellurocyanate is obtained from tellurium and potassium cyanide in DMSO. Aryl tellurium cyanides are probably formed as intermediates that disproportionate to the diaryl tellurium products and tellurium dicyanide2. 

Diaryl tellurium dichlorides, obtainable from aromatic compounds and tellurium tetrachloride, react with excess bromine or iodine in refluxing DMF or acetonitrile in the presence of a metal fluoride to give aryl halides in low yields. The reactions with chlorinating agents are very sluggish. The reaction of bromine and bis[4-methoxyphenyl] tellurium dichloride formed 2,4-dibromomethoxybenzene in 76% yield. Reactions of these tellurium dichlorides with copper(I) cyanide in DMF produced aryl cyanides in yields of less than 8%3. 

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