Cage octaphenylsilsesquioxane from cyclic tetrasiloxanetetraol and its sodium salt

Cage octasilsesquioxane with various substituents were obtained by the condensation reaction of various all-cis cyclic tetrasiloxanetetraol (R-T4-tetraol, R = phenyl, p-tolyl, i-butyl, naphthyl) with benzyltrimethylammonium hydroxide or tetrabutylammonium fluoride as a catalyst. Co-condensation of phenyl-T4-tetraol with phenyl-d5-T4-tetraol or with p-tolyl-T4-tetraol were found to proceed through reshuffling process evidenced by scrambling of the substituents. Pure octa(4-bromo-substituted phenyl)octasilsesquioxane was synthesized for the first time from tetra(4-bromo-substituted phenyl)tetrasiloxanetetraol sodium salt.