10.1021/jo001248+
The research focuses on the preparation, NMR spectroscopy, and theoretical studies of tris(trimethylsilyl)sulfonium and methylbis(trimethylsilyl)sulfonium ions. These ions were prepared as long-lived species through reactions involving trimethylsilane, trityl tetrakis(pentafluorophenyl)borate (Ph3C+ TPFPB), and precursor sulfides such as hexamethyldisilathiane and methylthiotrimethylsilane. The resulting ions were characterized using 1H, 13C, and 29Si NMR spectroscopy at -78 °C. The study also attempted the synthesis of dimethyl(trimethylsilyl)sulfonium ion but was unsuccessful due to the formation of the more stable trimethylsulfonium ion. The structures and NMR chemical shifts of the ions were calculated using density functional theory (DFT) and IGLO methods, with results aligning well with experimental data.