title: Kinetics and mechanism of the Co(II)-assisted oxidation of thioureas by dioxygen.
abstract: Catalytic oxidation of N,N'-dimethylthiourea and thiourea by dioxygen in water using a new cobalt(II) complex of octasulfophenyltetrapyrazinoporphyrazine was performed under mild conditions. The reaction is shown to include the formation of an intermediate anionic five-coordinate complex followed by an unusual two-electron oxidation to produce the corresponding urea and elemental sulfur (S8). Kinetic and thermodynamic parameters for the different reaction steps of the process were determined. Drastic differences in catalytic activity of cobalt and iron octasulfophenyltetrapyrazinoporphyrazines were observed.
authors.affiliation: Institute for Inorganic Chemistry, University of Erlangen-Nurnberg, Egerlandstrasse 1, 91058 Erlangen, Germany.
authors.forename: Evgeny V
authors.initials: EV
authors.lastname: Kudrik
authors.forename: Alexander
authors.initials: A
authors.lastname: Theodoridis
authors.forename: Rudi
authors.initials: R
authors.lastname: van Eldik
authors.forename: Sergei V
authors.initials: SV
authors.lastname: Makarov
mesh_terms: D002384:Catalysis; D003035:Cobalt / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008024:Ligands; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D013890:Thiourea / Q000031:analogs & derivatives / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D014867:Water; D003035:Cobalt; D013890:Thiourea; D010100:Oxygen