Klaus Dieter Asmus

Formation of a two-centre, three-electron, sulphur–sulphur bond in the gas phase

The dimer formed in the gas-phase reaction of ionized di-isopropyl sulphide with its neutral analogue is shown to possess a strong sulphur–sulphur bond.

Formation of sulfur-centered cation radicals by photofragmentation

Abstract The selected dialkyl dithioethers 1,5-dithiocane, 1,4-dithiepane, 1,4-dithiane, and 2,6-dithiaheptane are readily monoalkylated in nitromethane by tert-butyl O-trifluoromethanesulfonyl-3-hydroxyperoxypropanoate, 6 , to give the corresponding sulfonium salt peresters 2a-c , and 3 in good yield. Laser flash photolysis of these compounds affords the known two-sulfur, three-electron stabilized cation radicals 2a , b , and 5 which were characterized by optical absorption spectroscopy.

ANODIC OXIDATION OF 1,n-HALO(ALKYLTHIO)ALKANES AND 1,n-CHLORO(ALKYLSULFINYL)ALKANES

Abstract Anodic oxidation of 1,n-halo(alkylthio)alkanes [X-(CH2)n-S-R, X = Cl, Br, I] and l,nhalo(alkylsulfinyl)alkanes [Cl-(CH2)n-S(O)-R] was studied by cyclic voltammetry in anhydrous acetonitrile and by controlled potential electrolyses. The ease of sulfur oxidation was not affected by the alkyl substituents R or the number of methylene groups n in compounds with n > 2. The oxidation of the 1,2-halo(alkylthio)ethanes (n = 2) occurred at slightly higher potentials. The peak potentials decreased slightly in the order Cl > Br > I which is probably due to the electronegativity of the halogen atoms. The investigated anodic oxidation was shown to be a two electron irreversible process. Electrolyses in aqueous acetronitrile led to the corresponding sulfoxides and sulfones in good yields.