Unsymmetrical diorganyl tellurides

A different approach to unsymmetrical diorganyl tellurides, in which an electrophilic tellurium species is used, involves the nucleophilic attack of organomagnesium or organo-lithium reagents to diorganyl ditellurides. 

Unsymmetrical diorganyl tellurides (general procedure). A solution of the ditelluride (2 nunol) in THE (30 mL) is treated dropwise at 0°C under N2 with Br2 (0.32 g, 3 mmol)... 

Diorganyl tellurides, compounds with two organic groups linked to a tellurium atom, constitute the most abundant and famihar class of organic tellurium compounds. The organic groups, of the most differentiated types, can be identical or different, giving rise to symmetrical or unsymmetrical tellurides. 

Diorganyl mono- and ditellurides are the best-known classes of organic tellurium compounds comprising symmetric and unsymmetric alkyl, aryl, and alkyl-aryl tellurides. In addition to acyclic tellurides, heterocychc aliphatic telluroethers as well as aromatic tellurophene-derivatives are known (for a review, see Ref 36). 

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