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 [(CH<sub>3</sub>)<sub>2</sub>CHOC(S)]<sub>2</sub>S with SO<sub>2</sub>Cl<sub>2</sub> 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.