Total Control on the Synthesis of Regio and Stereoisomers of Vinylic Tellurides.

Abstract Methodologies for the total control on the synthesis of E, Z or 1,1-dissubstituted vinylic tellurides are described. Tellurobutadienes bearing the butyltellurium moiety at carbon 2 or at carbon 1 with E or Z configuration at the tellurium containing double bond were also obtained. Addition of diisobutylaluminum butyltellurolate to terminal alkynes resulted in the formation of 1-(butylteluro)-1-(organyl) ethenes in 45–75 % yield. Al/Te exchange reaction on vinyl alanes with butyl tellurenyl bromide/LiCl furnished the isomers of E configuration in 50–60 % yield. Vinylic tellurides of Z configuration at the double bond formed were obtained in 30–51 % yield by the hydroalumination of acetylenic tellurides.