Trichlates, an Unattended Class of Compounds: Characterization of Cl3CSO2Cl, and (H5O2)

Chlorination of CS2 leads to trichloromethanesulfenyl chloride, Cl3CSCl, in moderate yields. The oxidation of Cl3CSCl with H2O2 gives Cl3CSO2Cl, the chloride of trichloromethanesulfonic acid. Cl3CSO2Cl is the crucial product for the preparation of trichloromethanesulfonates (“trichlates”) and has been characterized by IR spectroscopy, differential scanning calorimetry (DSC) and X‐ray diffraction measurements (P‐1, a=609.99(5) pm, b=727.45(6) pm, c=782.49(7) pm, α=80.644(3)°, β=85.175(3)°, γ=88.311(3)°. The acid Cl3CSO3H can be gained in form of the hydrate (H5O2)[Cl3CSO3] in two different modifications (I: monoclinic, P21/n, Z=8, a=1292.47(7) pm, b=605.89(2) pm, c=2661.1(1) pm, β=98.708(4)°, V=1672.8(1) Å3; II: monoclinic, Cc, Z=4, a=699.80(5) pm, b=1054.72(8) pm, c=1139.88(8) pm, β=95.303(3)°, V=837.7(1) Å3. Both modifications have been investigated by IR spectroscopy, thermal analyses and theoretical calculations.