From bis triphenylstannyl telluride and alkylating reagents

The title reagent (prepared by the reaction of sodium hydrogen telluride with chlorotriph-enylstannane) reacts easily with the more active halides such as benzyl bromides whereas common halides need to be activated by cesium fluoride. 

Alkyl iodides and bromides react satisfactorily under these conditions whereas alkyl chlorides and aryl halides are nonreactive. 

Dialkyl tellurides (general procedure) Bis(triphenylstannyl) telluride (1 equiv), alkyl halide (2 equiv), excess CsF (4 equiv) and the solvent (MeCN or MeCN/THF) are mixed, kept nnder N2 and monitored by thin layer chromatography (TLC) (or NMR). Usual work-up of the mixture yields the telluride. 

Takahashi, H. Uemura, S. Sugita, N. Nippon Kagaku Kaishi 1987, 1469. 

Kozyzkin, B. L Salamtin, B. A. Ivanov, L. L. Kuzovlev, I. A. Gribov, B. G. Federov, V. A. Poluch. Anal. Veshchestv Osoboi Chist [Bold. Vses. Konf.] 1976, 5, 142, Chem. Abstr. 1979, 91, 140278. 

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