Organyl tellurolates

In contrast, tellurium insertion in alkyl- or aryllithium compounds followed by alkylation is a useful method for the synthesis of unsymmetrical tellurides. (For a tabulation of unsymmetrical tellurides prepared by alkylation of organyl tellurolates, see ref. 8.)... 

Actually, the method of choice for the preparation of organyl tellurolate anions is the reduction of diorganyl ditellurides with reducing agents. 

The arylation of organyl tellurolates, restricted first to aryl halides activated by electron-withdrawing groups,2 or requiring special conditions such as heating in HMPA in the presence of Cul, or photostimulation in liquid ammonia,ijggjj achieved successfully with non-activated aryl halides under normal conditions. ... 

Organyl tellurols are very unstable compounds owing to their extreme sensitivity to oxygen, giving the corresponding ditellurides. The first short-chain alkyltellurols (C1-C4) have been isolated as yellow liquids with an obnoxious odour, from the reaction of aluminium telluride and hydrogen telluride, respectively, with alcohols and aUcyl bromides. Aryltellurols seem not to have been isolated. As shown in Sections 3.1.3.2 and 3.2.2, aryl tellurolates are... 

Bis-organyl telluromethanes or organyl telluroketals, can be prepared by the conventional method involving the reaction of 2 equiv of organyl tellurolates with dihalomethanes. 

From organyl tellurols or tellurolates and terminal acetylenes... 

From organyl tellurolate (and telluride) anions and vinyl bromides... 

Organyl tellurolate anions effect 1,4-additions to acetylenes bearing electron-withdrawing groups such as acetylenic ketones, aldehydes, esters, diacetylenic ketones, " as well as acetylenic phosphonates and sulphones giving 2-substituted vinyl tellurides with Z configuration. 

Organyl tellurolates are unstable, air-sensitive species and are normally used in situ without isolation. Some methods... 

One convenient method for the preparation of organyl tellurolates is the treatment of diorganyl ditellurides with NaBH4. 

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