106726-64-1Relevant articles and documents
Cycloaddition reactions of dichlorodithionitronium hexafluoroarsenate(V) with alkynes and alkenes; the preparation and X-ray crystal structure of 1,3-dichloro-1,3,2-dithiazolidinium hexafluoroarsenate(V)
Parsons, Simon,Passmore, Jack,Schriver, Melbourne J.,White, Peter S.
, p. 852 - 862 (2007/10/02)
The dichlorodithionitronium cation, ClSNSCl+, undergoes symmetry-allowed, concerted, cycloaddition reactions with alkynes and alkenes in liquid sulphur dioxide.With ethyne and propyne it gives corresponding 1,3,2-dithiazolium salts in quantitative yield.Cycloaddition with alkenes yields (hitherto unknown) 1,3-dichloro-1,3,2-dithiazolidinium cations.The reactions are sensitive to substituents, and only the cycloaddition with ethene occurs quantitatively on a preparative scale.Cycloadditions with propyne and E- and Z-2-butene have been observed in solution.The preparation, characterization, and X-ray crystal structure of the product of the reaction of ClSNSCl+ with ethene, 1,3-dichloro-1,3,2-dithiazolidinium hexafluoroarsenate(V), are reproted.Crystals of 1,3-dichloro-1,3,2-dithiazolidinium hexafluoroarsenate(V) are monoclinic, of space group P21/c, a = 6.3161(6) Angstroem, b = 17.1724(23) Angstroem, c = 19.1558(18) Angstroem, and β = 98.143(8) deg; Z = 4 and R = 0.061.The 1,3-dichloro-1,3,2-dithiazolidinium cation consists of a five-membered ring, axially substituted at the sulphurs by chlorine (average bond lengths: S-N 1.603(8) Angstroem, S-Cl 2.025(4) Angstroem, S-C 1.822(10) Angstroem, and C-C- 1.504(13) Angstroem).Two crystallographically unique cations are linked by weak S..N contacts into pseudo-dimers.These data are used, together with structural comparisons with related SNS-containing cations and the sulphoxides and the 14N chemical shift, to show that the bonding in the SNS region of the cation is best represented by the valence canonicals and , such that the sulphur and nitrogen atoms respectively carry absolute positive and negative charges.This picture is also supported by the fluoride contacts to the cation from the AsF6- anion, which are exclusively to sulphur.Nuclear magnetic resonance data were consistent with the retention of the solid state structure of in solution.
