Telluride dihalides halides

The diaryl tellurides combine with halogens to form dihalides, R2TeX2, and with mercuric halides mercurihalides are produced, R2Te.HgX2. 

A reaction sequence starting with bis[phenyltelluro]mcthane leads to the insertion of a methylene group into the carbon-halogen bond of an alkyl halide. The bis[phenyltelluro] methane is reacted with butyl lithium to yield lithiomethyl phenyl telluride, which combines with an alkyl halide. The resulting alkylmethyl phenyl tellurium is converted to the tellurium dihalide, which in turn decomposes to an alkylmethyl halide when kept under vacuum at 250 6 or heated in DMF in the presence of a sodium halide at 100°7. 

Similar reactions between aluminum telluride and 1,5-dihalopentanes produced 5-halopentyl pentamethylene telluronium halides and pentane-1,5-diyl bis[pentamethylene telluronium] dihalides. ... 

Reduction of Organoselenium and -tellurium Halides and Oxides. TUD reduces aryltellurium trihalides to diaryl ditel-lurides (eq 2) and diorganyltellurium dihalides and telluroxides to diorganyl tellurides (eq 3) in high yield. The corresponding selenium compounds are reduced similarly. Some examples are given in Table 2. The reduction is performed by premixing the substrate and 2 N NaOH at room temperature for 15 min prior to the addition of TUD in petroleum ether. 

Among the many recent reports concerning telluranes, little is to be found of significant organic chemical interest, though a synthesis of biaryls from bis(aryl)tellurium dihalides or diary] tellurides by treatment with degassed Raney nickel is notable. Some leading references are 2%, 297, and also others discussed in the Sulphenyl Halides section. 

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