S-(Trimethoxysilylmethyl)- and S-(Silatranylmethyl)isothiuronium Halides and Their N-Substituted Derivatives

Previously unknown S-(trimethoxysilylmethyl)- and S-(silatranylmethyl)isothiuronium halides and their N-substituted derivatives were prepared. According to the IR and UV spectra, these compounds exist in the solid state and in methanol and acetonitrile solutions in the form of two equilibrium salt structures: those with the positively charged nitrogen and carbon atoms, or predominantly in one of these. In solutions of the iodides in highly polar acetonitrile, the first salt structure can occur in an equilibrium with its dissociation products, S-organylisothiourea (or its N-substituted derivative) and hydrogen iodide.