Oxygen species, mononuclear

R. Mason, Catalysis in chemistry and biochemistry, Catal. Lett., 2004, 98, 1. M. Che, A. J. Tench, Characterisation and reactivity of mononuclear oxygen species on oxide surfaces, Adv. Catal., 1982, 31, 78. 

The purpose of this review is to survey the work on adsorbed molecular oxygen species and to show how recent developments point the way toward an understanding of the role that they and the mononuclear forms of oxygen may play in oxidation reactions. The coverage is restricted to those papers where there is direct evidence on the nature of the oxygen species concerned. 

The mechanism of photo-oxidation of alcohols over Ti02 is not certain. Bickley (206, 405) postulates that the oxidation of isopropanol occurs via attack by OJ to form an aldehydic intermediate, which is then further oxidized by H202 or OH- to form acetone whereas Formenti and Teichner (406) suggest that oxidation occurs via a mononuclear oxygen species which at higher temperatures may involve activated lattice ions (417). This latter suggestion is very similar to the work on UV formation of O ions on the surface in a variety of oxides which have been reviewed previously (1). 

VII. The Relation of Mononuclear Surface Oxygen Species to Electron Spectroscopic and Catalysis Studies... 

Characterization and Reactivity of Mononuclear Oxygen Species on Oxide Surfaces M. Che and A. J. Tench Sulfur Poisoning of Metals C. H. Bartholomew, P. K. Agrawal, and... 

Characterization and Reactivity of Mononuclear Oxygen Species on Oxide Surfaces... 

For this reason, the present review is restricted to mononuclear oxygen species, such as the O ion, but it has also been broadened in scope to include the nonparamagnetic surface oxide ion O2 . Recent spectroscopic measurements have shown that O2 has unusual properties when it is in a situation of low coordination on the surface. Other mononuclear forms of oxygen such as charged O+ and O2 + ions are known in the gas phase, but in view of the high ionization potential of the O atom (2) given below, these species are unlikely to be stabilized on the surface ... 

The synthesis, structure, and superoxide dismutase mimetic activity in vitro and the protection against reactive oxygen species in vivo of mononuclear copper complexes with 2-(4-methylphenylsulfamoyl)-6-nitrobenzothiazole have been reported [602], Like 1,2,3-benzoxadiazoles, nitroderivatives of 1,2,3-benzothiadiazoles were obtained on diazotization of the corresponding or/Zzo-aminothiophcnolcs [213, 218, 583], The initial or/Zzo-thiophcnols for this reaction were synthesized by nucleophilic substitution of halogen in ort/zo-halogenoanilines. It turned out that 4-nitro- and... 

Superoxide Reductase (see Iron Proteins with Mononuclear Active Sites). Detoxification of reactive oxygen species in anaerobic microorganisms has recently been shown to center around SOR, a novel mononuclear iron enzyme that reduces superoxide to hydrogen peroxide (see equation 4), rather than dismuting superoxide to oxygen and hydrogen peroxide as is the case for the superoxide dismutases found in aerobic organisms. 

---