Vibrational and Valence Photoelectron Spectroscopies, Matrix Photochemistry, and Conformational Studies of ClC(O)SSCl

ClC(O)SSCl was prepared by an improved method by the reaction of [(CH3)2CHOC(S)]2S with SO2Cl2 in hexane. The photoelectron spectra in the gas phase present four distinct regions, corresponding to ionizations from electrons formally located at the S, O, and Cl atoms and at the CO bond. The vibrational IR and Raman spectra of the liquid were interpreted in terms of the most stable syn–gauche conformer (the OC double bond syn with respect to the SS single bond and the CS single bond gauche with respect to the SCl single bond) in equilibrium with the less stable anti–gauche form, both occurring in two enantiomeric forms. The randomization process between the conformers was induced by broad-band UV–visible irradiation in matrix conditions, and several photoproducts were identified by FTIR spectroscopy. The experimental results were complemented by theoretical calculations.