22665-15-2Relevant academic research and scientific papers
Reactive ligands in radical processes catalyzed by copper complexes
Tarkhanova,Gantman
, p. 82 - 88 (2011)
The effect of the reactivity of donor ligands on the catalytic properties of copper complexes in the oxidative dimerization of mercaptans is considered. Catalytic compositions containing metal complexes in an excess of organic reagent ligands, which can show pronounced reductive properties (aromatic amines) or, on the contrary, oxidative properties (dimethyl sulfoxide) toward substrates, exhibit the greatest activity. In the course of the oxidation of mercaptans catalyzed by copper complexes, redox reactions accompanied by not only a change in the oxidation state of the metal but also the direct interaction of a substrate with an organic donor occur. In the presence of aromatic amines, the coupled oxidation of thiols and amines occurs, whereas dimethyl sulfoxide participates in the reaction as an oxidizing agent.
Substituent Effect On The Stability Of The Hydroxyl Radical Adduct Of α-Phenyl N-tert-Butyl Nitrone (PBN)
Janzen, Edward G.,Hinton, Randall D.,Kotake, Yashige
, p. 1257 - 1260 (2007/10/02)
α-Hydroxy-(3- and 4-substituted)-benzyl tert-butyl aminoxyl radicals, the hydroxyl radical spin adducts of 3- and 4-substituted α-phenyl N-tertbutyl nitrones (R-PBN's), decay rapidly (in seconds) by first order kinetics in acetonitrile (ACN).The Hammett equation is obeyed with p = -1.36 and r = 0.90.Polar solvents produce an increase in rate of decay: water (fast) > ACN (fast) > benzene (slow).Thus substantial charge separation in the transition state is indicated.The mechanism proposed is a unimolecular cleavage reaction producing the substituted benzaldehyde and tert-buty nitroso anion radical: .Support for this mechanism is provided by the detection of tert-butyl hydroaminoxyl when the decay is studied in water. Key Words: EPR, PBN, Hammett Equation, Spin Trapping, Spin Adduct
On the Use of Glyoxal Bis(t-Butyl Nitrone) as a Spin Trap
Rehorek, Detlef,Janzen, Edward G.
, p. 968 - 982 (2007/10/02)
Nitroxides derived from glyoxal bis(t-butyl nitrone), GBBN, have been studied by e.s.r. spectroscopy.Well resolved e.s.r. spectra exhibiting extra hyperfine splitting by magnetic active nuclei in γ-position have been recorded for the spin adducts of alkyl, as well as .N3 and .CH2Cl radicals.Enhanced stability was found for the spin adducts of halogen atoms.However, a wider application of this spin trap is limited by the strong superposition of the e.s.r. signals of different radical spin adducts which is directly related to almost identical conformations of these nitroxides.
Spin-trapping with 2-methyl-2-nitrosopropane: photochemistry of carbonyl-containing compounds. Methyl radical formation from dimethyl sulfoxide
Rosenthal, Ionel,Mossoba, Magdi M.,Riesz, Peter
, p. 1486 - 1492 (2007/10/02)
The photochemical reactions of several carbonyl-containing compounds investigated by spin-trapping with 2-methyl-2-nitrosopropane revealed different modes of scission depending on the structure of the initial compound.Thus, in photo-Fries rearrangements, the acyl radical was detected. 1,3-diphenyl-2-propanone decarbonylated to yield the benzyl radical.Finally, valerophenone yielded the radicals expected by γ-hydrogen abstraction.In a dark reaction, dimethyl sulfoxide reacts with NaOH to generate methyl radicals.The latter result suggests the need for caution in the use of dimethyl sulfoxide with 2-methyl-2-nitrosopropane for the detection of hydroxyl radicals.
