Alkynes to Vinyl Lithiums

Phenylacetylene and sodium telluride combine to produce bis[(Z)-2-phenylethenyl] tellurium, while phenylacetylene and sodium butanetellurolate or sodium benzenetel-lurolate yields organo (Z)-2-phenylethenyl telluriums. These vinyl telluriums are cleaved by butyl lithium in tetrahydrofuran at -78 to (Z)-2-phenylethenyl lithiums. 

Ethynyl phenyl telluriums, obtained from ethynyl lithiums and phenyl tellurium halide, are carboxylated in methanol in the presence of triethylamine and palladium(II) chloride to methyl ethynylcarboxylates. l,4-Diorgano-l,3-butadiynes are by-products in these reactions. 

Irgolic Organo Tellurium Compounds with 2 Te —C Bonds or 1 Te = C Bond 

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