Tellurol

Tellurols are analogues of alcohols and phenols where tellurium replaces oxygen. Tellurols, selenols, and thiols have similar properties, but tellurols are the least stable. Although they are fundamental representatives of organotellurium compounds, tellurols are lightly studied because of their instability. Tellurol derivatives include telluroesters (RC(O)TeR') and tellurocyanates (RTeCN).

Alkyltellurols are yellow liquids with a strong odors. Aryltellurols form colorless crystals. More stable than these compounds are the organoelement tellurols. These fairly stable compounds have the formulae (Me₃Si)₃CTeH, (Me₃Si)₃SiTeH, and (Me₃Si)₃GeTeH.

The acidity of tellurols can be inferred by the acidity and dissociation constant of hydrogen telluride, H₂Te, which has a (first) pK_a of 2.64 corresponding to a dissociation constant of 2.3 × 10^−3.5. H₂Te has a lower pK_a and higher dissociation constant than H₂S and H₂Se.

The absence of hydrogen-bonding explains the low boiling temperature of tellurols. The Te–H bond in tellurols is weak. Tellurols are easily oxidized and decompose thermally. Ultraviolet light also induces decomposition. Methanetellurol decomposes to dimethyl ditelluride and hydrogen.

The first tellurol to be synthesized, ethanetellurol, was prepared in 1926 via the Grignard reagent. The most frequently used method involves reduction of the ditellurides (R₂Te₂).

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