Insights into the Hydrolytic Polymerization of Trimethoxymethylsilane. Crystal Structure of (MeO)₂MeSiONa

Abstract

The commercially practiced conversion of trimethoxymethylsilane (MTM) to [OSi­(OMe)­Me)]_<i>n</i> polymers and resins is assumed to proceed via the silanol (MeO)₂MeSiOH. Access to this crucial silanol is gained via the synthesis of (MeO)₂MeSiONa, the first methoxysilanoate to be crystallographically characterized. Mild protonation of this silanoate gives (MeO)₂MeSiOH, which is shown to condense with (MeO)₂MeSiOH but not with MTM. Condensation generates reactive disiloxanols but does not produce symmetric disiloxanes. Parallel results were obtained with (MeO)₂PhSiOH