The reaction of tellurium tetrachloride and aryltellurium trichloride with simple olefins and γ, σ-unsaturated acids has been studied. Cyclohexene gives normal products of addition while styrene, di-isobutylene and 1, 4-diphenylbutadiene-1, 3 do not react with aryltellurium trichlorides and give rise to elementary tellurium when treated with tellurium tetrachloride. In the case of the unsaturated acids lactonization occurs due to the participation of the ...