Spectroscopic, Theoretical, and Electrochemical Studies of 1,2-Dithiins

The lowest oxidation potentials for 1,2-dithiins are in the range of 0.67-0.96 V in acetonitrile and 0.81-1.04 V in dichloromethane. These oxidation potentials are less anodic than expected based on the ionization potentials of 1,2-dithiin determined by photoelectron spectroscopy. Theoretical calculations suggest that the reason for this difference is a change in optimized geometry between 1,2-dithiin and its oxidized species.