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The Raman spectra (3500–20 cm−1) of gaseous, liquid and solid and the infrared spectra (4000–50 cm−1) of gaseous and solid trimethoxyborane, B(OCH)3, were recorded. Qualitative depolarization values were obtained from the Raman spectrum of the liquid. All normal modes, except the torsions, were assigned based on infrared band contours, depolarization values, group frequencies and normal coordinate calculations. From a comparison of the spectra in the fluid states with that from the solid, it is concluded that the molecule exists predominantly in a single conformation in all physical states. Frequencies and potential energy distributions for the normal modes were calculated with the force constants obtained from ab initio calculations with the 3–21G basis set. A comparison of these calculated frequencies with the observed spectra is consistent with the predominant form having a ‘planar’ heavy atom skeleton with C3h symmetry. In was not possible to determine an experimental barrier to rotation about the BO bond. No change was observed in the 13C NMR spectrum over the temperature range of 22 to −90°C. Structural parameters, conformational stability and barriers to internal rotation were obtained from ab initio Hartree–Fock gradient calculations employing both the 3–21G and 6–31G* basis sets. The results are compared with the corresponding data for some similar organoboranes.

The infrared (4000-50 cm−1) and Raman spectra (3500-10 cm−1) have been recorded for dimethylmethoxyborane, (CH3)2BOCH3, in both the gaseous and solid states. Additionally, the Raman spectrum of the liquid has been recorded and qualitative depolarization values obtained. Only one conformation has been found in all three physical states and, on the basis of the polarized nature of the Raman band assigned as the BC2 antisymmetric stretch, this conformer is identified as being the “planar” form with Cs molecular symmetry. A complete vibrational assignment is proposed based on the depolarization data, infrared gas phase band contours, and group frequencies. Additionally, variable temperature 13C NMR studies have been carried out and the barrier to rotation about the BO bond has been determined as 8.9 kcal mol−1. Structural parameters have been obtained from ab initio Hartree—Fock gradient calculations employing 3-21G and 6-31G* basis sets. The results are compared with the rα values obtained earlier from an electron-diffraction study. Potential-surface calculations have been carried out to determine the conformational stability and barriers to internal rotation. Frequencies and potential-energy distributions for the normal modes have been calculated utilizing the 3-21G basis set. All results are compared to the corresponding data for some other organoboranes.

Iodosobenzene in the presence of catalytic amount of benzeneseleninic acid oxidized various sulfides to sulfoxides through ligand coupling on the iodine atom in excellent yields in acetonitrile under mild conditions.