Tellurium Cyanide

The tellurium cyanide may be obtained as a colourless solution on extraction with ether. On evaporation and crystallisation of this solution a double compound of cyanide and ether is obtained, from which the pure cyanide may be prepared by distillation in vacuo. 

From Phenyl Tellurium Cyanide, Divinyl Tellurium, Alkyl Ethynyl Telluriums, or Bis[benzoyl] Tellurium Compounds... 

Phenyl tellurium cyanide was reduced with sodium borohydride in ethanol to sodium benzenetellurolate4. 

Benzyl tellurium cyanide and phenylmethanethiol in carbon tetrachloride at 20° formed benzyl phenylmethylthio tellurium2. 

Benzyl Phenylmethylthio Tellurium2 0.123 g (0.5 mmol) of benzyl tellurium cyanide and 0.062 g (0.5 mmol) of phenylmethanethiol arc dissolved in carbon tetrachloride and the mixture is stirred for 20 min. The solvent is then evaporated and the residue is recrystallized from petroleum ether yellow prisms m. p. 69°. 

Tellurocyanate ion reacts with benzyl halides1-3, aryl iodides10, arenediazonium tetraflu-oroborates4, and with azulene11 to form aryl tellurium cyanides. 

Organo tellurium halides treated with potassium or silver cyanide were converted to organyl tellurium cyanides (p. 366). 

Tetraphenylarsonium benzyl(bromocyanato)tellumte(II) was prepared from benzyl tellurium cyanide and the arsonium bromide3 and also from tetraphenylarsonium tellurocya-nate and benzyl bromide4. 

Potassium tellurocyanate, prepared from potassium cyanide and tellurium in DMSO, reacts with benzyl halides to produce benzyl tellurium cyanides in good yields. Because of the sensitivity of potassium tellurocyanate to oxygen and of some of the benzyl tellurium cyanides to light, the reactions must be carried out in an inert atmosphere (nitrogen or argon) under red light. 

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. 

Azulenyl tellurium cyanide was synthesized from potassium tellurocyanate and azulene7. 

Diaryl ditellurium compounds and potassium cyanide produced aryl tellurium cyanides in low yields when stirred in dimethyl sulfoxide at 20°8. 

Phenyl tellurium cyanide was obtained from sodium benzenetellurolate and cyanogen bromide2. 

The reactions of organo tellurium cyanides are largely unexplored. Benzyl tellurium cyanides reacted with the stoichiometrically required amounts of bromine to yield benzyl tellurium tribromides4,5. An excess of bromine caused deposition of tellurium and the formation of benzyl bromide5. 

Treatment of benzyl tellurium cyanide with methanolic sodium hydroxide yielded dibenzyl ditellurium5. Benzyl and substituted benzyl tellurium cyanides were reduced to dibenzyl ditellurium compounds by hypophosphorous acid5,6. 

Irradiation of a chloroform solution of benzyl tellurium cyanide under an oxygen atmosphere with an UV lamp produced benzaldehyde and benzyl alcohol5. 

Phenyl tellurium cyanide reacted with cyclohexene1,2, alcohols3, and haloamino acids4. 

Phenyl tellurium cyanide is converted to sodium benzenetellurolate by an ethanolic solution of sodium borohydride4,5. 

Methoxyphenyl tellurium cyanide and poly(4-lithiostyrene) produced a 4-methoxy-phenyltelluro-substituted polymer6. 

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. 

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 reactions2. 

Dodecyl Phenyl Tellurium2 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 co-amino-cu-carboxyalkyl telluriums3. 

Cyanogen halides combine with diaryl tellurium in diethyl ether solution to form diaryl tellurium cyanide halides in 80 100% yields1-3. 

Cyanide has the possibility of bonding to tellurium via the C atom or the N atom. The v(CN) absorption for nitriles, R-CN, occurs at 2260-2220 cm-1, and for isonitriles, R-NC, at 2160-2120 cm-1. However, the single crystal X-ray structural analysis of 4-nitrobenzyl tellurium cyanide showed that the cyanide group is bonded to the tellurium atom via the carbon atom1. Thus, di- and triorgano tellurium cyanides are discussed here. 

Triphenyl tellurium cyanide (triphenyl telluronium cyanide) was prepared by passing an ethanolic solution of triphenyl telluronium chloride through an anion exchange column in the cyanide form1. 

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