Polymeric Organic Tellurium Compounds

Dimethyl and methyl phenyl 4,4-dimethyl-2,6-dioxocyclohexylidene tellurium compounds transferred a methyl group to triethylamine, triphenylphosphane, tris[di-methylamino]phosphane, and triphenylarsane. The methyl onium cations were isolated as tetraphenylborates. The alkylidene organo telluronium intermediate was identified by P-NMR spectroscopy in the reaction of the ylide with tris[dimethylamino]phosphanek 

Hexamethyl tellurium is thus far the only known compound of this type. It was obtained from tetramethyl tellurium difluoride and dimethyl zinc. Hexamethyl tellurium survived being heated at 140° for 4.5 hours. 

The few polymeric materials containing organic groups and tellurium as repeating units are poly(alkylene tellurium), poly(arylene tellurium), and the corresponding ditellurium compounds. These polymers were prepared to allow the exploration of their eleetrical properties. 

Another group of polymeric organic tellurium compounds was obtained from diphenyl tellurium dichloride and disilver salts of dicarboxylic acids. 

Tellurium and 4,4 -dilithioarenes reacted in tetrahydrofuran to form poly(4,4 -arylene ditellurium) polymers.  

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Bis-[iodomethyl tellurium, the only isolated representative of this class of organic tellurium compounds, was obtained by reduction of bis[iodomethyl] tellurium diiodide with potassium disulfite. The diiodide was prepared in widely fluctuating yields never exceeding 30% by heating amorphous tellurium and diiodomethane at 80° for 49 h1. Bis[iodomethyl] tellurium polymerizes in solution and on heating1. 

Polymeric tellurium compounds. Polymers containing tellurium were either prepared from precursors with two tellurium atoms in the molecule or by introduction of a tellurium functionality into an organic polymer. 

Tellurium has no significant biological role. Tellurium and tellurium compounds should be considered to be toxic and need to be handled with care. Organic tellurides have been employed as initiators for living radical polymerization, and electron-rich mono- and di-tellurides possess antioxidant activity. Humans exposed to as little as 0.01 mg/m or less in air develop "tellurium breath", which has a garlic-like odor. This is due to formation of ethyl telluride within the body. 

The identity of bis pentafluorophenyl ditellurium obtained by the reduction of pentafluoro-phenyl tellurium trichloride by zinc in ethanol6,7 seems to be uncertain8. l,4-Bis[trichlorotelluro]benzene9 and 2,2 -bis[trichlorotelluro]biphenyl10 were reduced to polymeric ditellurium compounds that were insoluble in organic solvents. 

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