Bismuth Tellurolates

Diethylstibano 4-Methylphenyl Tellurium A mixture of 0.72 g bis[4-methylphenyl] ditellurium (1.6 mmol) and 0.59 g tetraethyldistibane (1.6 mmol) is stirred under argon at 25° for 1 h. The orange, air-sensitive liquid (very soluble in non-polar solvents) is obtained in quantitative yield. 

Dimethyl ditellurium and tetramethyldistibane formed, within a few minutes at 20° in an exothermic reaction dimethylstibane methyl tellurium in quantitative yield. The reaction with tetraethyldistibane is best carried out at — 40° to prevent cleavage of carbon-antimony bonds. 

The air-sensitive dialkylstibano methyl tellurium compounds can be distilled under reduced pressure without disproportionation into tetraalkyldistibane and dimethyl ditellurium. Even at elevated temperature, disproportionation was not observed. However, diethylstibano methyl tellurium tends to decompose to triethylstibane and bis[methyltelluro] ethylstibane.  

The malodorous Sb — Te compounds are thermochromic with the color changes occurring at the melting points. The reversible color changes are probably caused by changes of intermolecular contacts during the phase transition.  

Diphenyl ditellurium reacted with tetramethyldibismuthine in diethyl ether at — 20° and with trimethylbismuthine in dichloromethane at 20° to form dimethylbismuthino phenyl tellurium.  

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These compounds are discussed in the Sections on Phosphorus, Arsenic, Antimony, and Bismuth Tellurolates (s.p. 198, 199). 

Nitrogen, Phosphorus, Arsenic, Antimony, and Bismuth Tellurolates... 

The tin(II) and lead(II) tellurides result from the amide M N(SiMe3)2k and tellurol. The tin derivative is dimeric with the Sn2Te2 unit adopting a butterfly-like structure with the terminal tellurol groups cis109. The antimony and bismuth derivatives result from amides and the tellurol96. 

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