Reactions of Sulfur Compounds with Ozone in Aqueous Solution

The aim of this paper was to shed some light on the mechanisms of ozone reactions with sulfur compounds. In thiolates and thiols, linear anionic and neutral trioxides, respectively, were formed in the first stage. The anionic trioxide could eliminate O2•– and 1O2, and could lead to the formation of the corresponding sulfinic peracid anion. The neutral trioxide could release 1O2 and could form the corresponding sulfinic peracid. Sulfinic peracids and their anions resulted from the internal rearrangement of certain cyclic trioxides derived from linear trioxides. This study can serve as a starting point for identifying the products generated in systems involving thiolates/thiols and ozone. The reaction of ozone with sulfides leads to the formation of a neutral linear trioxide that eliminates 1O2 either directly or via a cyclic trioxide. Another reaction investigated was that between dimethyl sulfoxide (DMSO) and ozone. The mechanism proceeds through the formation of a linear trioxide, followed by the direct elimination of 1O2. The temperature dependence of the second-order rate constant was determined as: kII=6.97⋅1011⋅e−  63000R⋅T M–1·s–1.