Syntheses, spectroscopic and structural properties of phenoxysilyl compounds: X-ray structures, FT-IR and DFT calculations

• X-ray molecular structures of three phenoxysilyl compounds are reported.
• Vibrational spectra of two polymorphs of phenoxysilanethiol are analyzed.
• The energy of intramolecular SH---π interaction is estimated from DFT calculations.
• DFT calculations are in good agreement with experimental results.

The reaction of silicon disulfide with alkylphenols yields tetraphenoxysilane, cyclodisilthiane and silanethiol. The outcome of the reaction depends on the presence of the steric hindrance in the ortho position on the reacting phenol. New products of the reaction of silicon disulfide with phenols are characterized by FT-IR, NMR, X-ray diffraction and DFT calculations. The intramolecular interactions in the compounds are mainly XH---π (X = C, S) whereas the intermolecular interactions are either very weak CH---π/CH---O contacts found in aryloxysilane or electrostatic dipole–dipole attraction in cyclodisilthiane and silanethiol. The S–H---π interactions in the obtained silanethiol are analyzed with the use of DFT/GGA BLYP-D XC potentials. The energy of intramolecular S–H---π interaction is estimated.

New products of the reaction of silicon disulfide with phenols: phenoxysilane, cyclodisilthiane and silanethiol have been characterized by FT-IR, NMR and X-ray diffraction. The outcome of the reaction depends on the presence of the steric hindrance in the ortho position of the reacting phenol. The intramolecular interactions in the compounds are mainly XH---pi (X = C, S) whereas the intermolecular interactions are very weak CH---π/CH---O contacts as in aryloxysilane or electrostatic dipole-dipole attractions in cyclodisilthiane and silanethiol. The energy of intramolecular S–H---π interaction is estimated with the use of DFT/GGA BLYP-D XC potentials.Figure optionsDownload as PowerPoint slide