Reactions of the methylsulfinyl radical [CH3(O)S•] with oxygen (3O2) in solid argon

Hans Peter Reisenauer, Jarosław Romański, Grzegorz Mlostoń, Peter R. Schreiner

Chem. Commun. 2015, 51, 10022–10025. DOI: 10.1039/c5cc02168e

Highlight: Holm Petzold, Nachr. Chem. 2015, 63, 760

The atmospherically highly relevant methylsulfinyl radical (CH3(O)S•) readily reacts with molecular triplet oxygen in cryogenic argon matrices containing small amounts of 3O2. Comparison of experimental and computed IR- and UV/Vis spectra, including isotope exchange, show that the initially formed 3O2 adduct has the structure of a peroxyl radical (CH3(O)SOO•), which upon irradiation with UV light isom-erizes to the methylsulfonoxyl radical (CH3SO3•). The latter transforms into the methansulfonic acid radical (•CH2SO3H) by irradiation with visible light. During the matrix photolysis small amounts of SO3 and methyl radical were detected indi-cating competitive direct photodissociation.