12-Membered highly unsaturated macrocyclic silahydrocarbon containing exocyclic methyl and benzyl groups is synthesized by the reaction of benzylmethyldi(bromomagnesiumethynyl)silane with dimethyldichlorosilane. Hydrosilylation of benzyl(triethynyl)silane with trichlorosilane with subsequent reaction of the formed adduct with trimethylsilylmagnesium bromide leads to the spherical dendrimer (N-C = 3) containing the benzyl group at the central Si atom, -CH=CH- groups in the inner sphere and numerous triple bonds on periphery. NMR spectra of the obtained compounds were studied.