Bis (trifluoromethyl) sulfone, CF3SO2CF3: synthesis, vibrational and conformational properties.

ABSTRACT

Bis (trifluoromethyl) sulfone, CF(3)SO(2)CF(3), was obtained as a byproduct in the synthesis of CF(3)SO(2)SCF(3). The compound was characterized by infrared and Raman spectroscopy as well quantum chemical calculations. Quantum mechanical calculations indicate the possible existence of two conformers symmetrically equivalent with C(2) symmetry. The preference for the staggered form was studied using the total energy scheme and the natural bond orbital (NBO) partition scheme. Additionally, the total potential energy was deconvoluted using a sixfold decomposition in terms of a Fourier-type expansion, showing that the hyperconjugative effect was dominant in stabilizing the staggered conformer. Infrared and Raman spectra of CF(3)SO(2)CF(3) were obtained. Harmonic vibrational wavenumbers and a scaled force field were calculated, leading to a final root mean-square deviation of 7.8 cm(-1) when comparing experimental and calculated wavenumbers.