Zwitterionic lambda Si-5-silicates with SiO2S2C skeletons: Syntheses and structural characterization in the solid state

The zwitterionic lambda Si-5-silicates [(dimethylammonio)methyl]bis[methane carboxylatothiolato(2-)-O,S]silicate (9) and bis[benzene-1-carboxylato-2-th iolato(2-)-O,S][(dimethylammonio)methyl]silicate (10) were synthesized by t reatment of the zwitterionic lambda Si-5-tetrafluorosilicate F4SiCH2NMe2H w ith two molar equivalents of Me3SiSCH2C(O)OSiMe3 and 1,2-Me3SiS-C6H4-C(O)OS iMe3, respectively (formation of four molar equivalents of Me3SiF). Compoun ds 9 and 10 were characterized by elemental analyses (C, H, N, S) and solid -state NMR studies (C-13, Si-29). In addition, compound 10 was structurally characterized by single-crystal X-ray diffraction.