Nature of 2?/1?* Three-Electron-Bonded Chlorine Adducts to Sulfoxides

Article abstract of DOI:10.1021/j100172a026

Reaction of sulfoxide radical cations, R2SO^.+, with chloride ions in acidic aqueous solutions (pH * electron.The same species is formed upon oxidation of sulfoxides by Cl2^*, although only with relatively low rate constants.The measured λ_max are 390, 400, and 410 nm for the R2SO...Cl species with R = Me, Et, and n-Pr, respectively.Equilibrium constants for R2SO^.+ + Cl^- <--> R2SO...Cl have been determined to be 560, 600, and 575 M^-1, for the same respective series of species (error limit +/- 20percent).It is considered that our three-electron-bonded species is identical with an electronically not further specified chlorine-atom adduct to sulfoxide, R2SO(Cl)^., observed earlier in sulfoxide-containing solutions of carbon tetrachloride and dichloromethane.The R2SO...Cl exhibit oxidizing properties and are shown to oxidize, for example organic sulfides and disulfides (rate constants on the order of 10⁸ M^-1 s^-1) or SCN^- (rate constants on the order of 10⁹ M^-1 s^-1).The optical and kinetic results are discussed in light of the electronic properties of the radical species.