Preparation of ethynylsilane dendrimers

A dendritic macromolecule containing 144 phenylethynyl groups was created. 1,3,5-tris(dimethylvinylsilyl)benzene (G0) as the core and bis(phenylethynyl)methylsilyl groups as progressing units were used. The first generation (G1P-9Cl) was obtained by the reaction of G0 with trichlorosilane and was followed by the phenylethynyl-group-containing generation (G1-9PA) by the reaction of lithium phenylacethylide. Using the continuous iterative reactions of trichlorosilane and lithium phenylacethylide, the dendritic molecule progressed to the second generation (G2-27PA). For the formation of a less crowded model, the reaction of the first generation (G1-9PA) with dichloromethylsilane was allowed to progress to the 18 SiCl bonded second generation (G2P-18Cl). After that, by the use of the two iterative reaction mechanisms, the fifth generation with 144 phenylethynyl groups containing the carbosilane dendrimer was prepared.