Tellurium alkoxides

Tellurium alkoxides were also prepared from the stoichiometrically required amounts of tellurium tetrachloride and alcohol in tetrahydrofuran, with triethylamine serving as the hydrogen halide-scavenger3. 

Tellurium tetraethoxide or tellurium tetraisopropoxide refluxed with acetyl chloride produced tellurium alkoxide chlorides3. 

Tellurium alkoxide chlorides are waxy solids or viscous liquids. The thermal stability of these compounds decreases with increasing chlorine content1. 

Tellurium tetraalkoxides and acetyl chloride reacted in benzene to produce tellurium alkoxide chlorides and alkyl acetate. The number of alkoxide groups remaining with the tellurium atom is determined by the molar ratio of the reagents3. 

The tellurium alkoxide trichlorides were isolated as adducts containing one mole of alkyl acetate per two moles of tellurium compound3. 

Diaryl tellurium oxides and dimethyl sulfate or diethyl sulfate reacted in hot methanol to give bis[diaryl tellurium alkoxide] sulfates1. 

Stirring diorgano tellurium diethoxides in a diethyl ether/pentane medium with the stoichiometrically required amounts of 1,2-dihydroxyethane, 1,3-dihydroxypropane, 2-hydroxyphenylmethanol, 1,2-dihydroxybenzene, 2,2 -dihydroxybiphenyl, 2,3-dihydroxy-naphthalene, or 4-methylphenol produced diorgano tellurium alkoxides and phenoxides. These compounds precipitated as white solids from the reaction mixtures or separated as oils that crystallized during storage at low temperatures. The products of the transesterification with diols could be oligomeric. The low solubility of these compounds prevented the determination of their molecular masses . 

Selenium and tellurium alkoxides are also highly volatile and tend to be monomeric. For example, ethoxo-, -butoxo-, and isopropoxo-derivatives of selenium have been volatilized at 76°C/10.0, 110°C77.0, and 88°C/4.5mm pressures, respectively. Similarly tellurium tetramethoxide, ethoxide, -butoxide, and isopropoxide distilled at 115°C/9.0, 107°C/5.0, 150°C/0.8, and 76°C/0.5mm pressure, respectively. 

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