Gas-phase structure of 4,4-difluoro-3-(pentafluorothio)-1,2-oxathietane-2,2-dioxide, SF5(CHCF2OS)over-bar-O-2

摘要

The gas-phase structure of 4,4-difluoro-3-(penrafluorothio)-1,2-oxathietane-2,2-dioxide, SF5CHCF2OSO2 (1), has been determined by gas electron diffraction; a planar structure of the four-membered sultone ring with a puckering angle of 1 +/- 5 degrees was found. This result is in contrast to a previous X-ray crystallographic study which reports a nonplanar ring conformation with a puckering angle of 14 degrees. The comparison between the gas-phase and crystal structures demonstrates that deformation of the ring in the solid state is due to intermolecular interactions (C-H ... O=S hydrogen bonds). The structural parameters of the sultone ring in SF5CHCF2OSO2 are compared with those in CF2CF2OSO2 and CHFCF2OSO2. (C) 1998 Elsevier Science B.V. [References: 15]