anti-Markovnikov addition of tellurium tetrachloride to trimethyl ethynyl silane

An investigation of the TeCl4 interaction with trimethyl ethynyl silane 1 in CHCl3 has shown that anti-Markovnikov adduct [Z-1-(trimethylsilyl)-2-chlorovinyl]tellurium trichloride is formed as the only product. In time, it is hydrolyzed to give [Z-1-(trimethylsilyl)-2-chlorovinyl]tellurium(hydroxy)-dichloride which, in turn, is dehydrated to afford bis[(2-chloro-1-trimethyl-silylvinyl)dichlorotellurium]oxide. These data revealed that the reaction studied was the first example of anti-Markovnikov syn-addition of TeCl4 to terminal acetylenes. A computed simulation of the TeCl4 interaction with ethynyl silane 1 in a gas state using PES method did not reveal dominating orientation of the addition but showed the conditions at which anti-Markovnikov addition can occur and which were probably met in carrying out the reaction in CHCl3.