Dioxygen species

Table 14.4 Effect of electron configuration and charge on the bond properties of dioxygen species...

The failures of CeOj alone or RhjOj alone to yield RO or 01-type paramagnetic centers, when subjected to the same experimental strategy as that which did yield such centers over RhOj/CeOj after T > 573 K, pointed to synergism between the RhO, and CeO components of the latter in producing at 300 K the dioxygen species required for 01 and for RO-type signals, possibly through the intermediacy of Rh-O-o-Ce and Rh-O-O-Ce interfacial sites. 

Taube H. 1986. Interaction of dioxygen species and metal ions—Equilibrium aspects. Prog Inorg Chem 34 607. 

These conclusions are supported by another ESR study (Jd) made on some oxygenated cobaltoximes(II), which showed that the dioxygen species finally formed is best characterized as a peroxo-bridged complex these being reversibly formed binuclear complexes. 

Step 2 Reaction between COg and surface oxygen or dioxygen species to give C02 (Eqn. 3) or carbonates (Eqn. 4)... 

A rare example of the activation of 02 and CO by platinum involves the treatment of the nucleophilic dioxygen species [Pt(02)(PPh3)2] with the electrophilic carbonyl ligand in [PtCl(CO)(PPh3)2]+ to afford a dinuclear cycloperoxycarbonyl adduct (116) in high yield.311... 

Compound Dioxygen species KO-O) n(M-0)s as Oxygen source Reference... 

Taube, Henry, Interaction of Dioxygen Species and Metal Ions—Equilibrium... 

Most known reactions of dioxygen species involve inner-sphere pathways, or adduct formation. Our studies of the... 

Hyperfine coupling constant, 22 267, 269 Hyperfine interaction, ESR data for, 22 274 Hyperfine parameters for O, 32 128-130 Hyperfine splitting, 31 81 Hyperfine structure, trimer species, 31 98-99 Hyperfine tensor, 22 267, 273-279, 336, 340 constants, 32 20-21 dioxygen species, 32 18-25 equivalent oxygen nuclei, 32 18-21 ionic oxides, 32 40... 

We found that a solution of [(TIMElSr )Co]Cl (3 -Co) reacts cleanly with dioxygen at room temperature to form the 1 1 cobalt dioxygen species [(TIMEN )Co(02)] (Fig. 16, -Co(02)). Infra-... 

Interactions and reactions of iron porphyrins with dioxygen species,with nitric oxide (see Section 5.4.3.8), with nitrite and with nitrate, and also of complexes containing carbon-bonded ligands, have continued to attract considerable interest and be reviewed. 

Reviews of kinetics and mechanisms deal with long-range electron transfer and with the uptake and release of dioxygen species, especially uptake from organic peroxides. " " The photochemistry of iron porphyrin complexes has been documented." ... 

Interaction of dioxygen species with Fe aq and with Fe " aq has been very briefly reviewed. In relation to 0x0-, peroxo-, and superoxo-complexes as models for intermediates in oxygenase activity, a brief report on a 2000 symposium on activation of oxygen summarizes the then-current situation in the search for a mechanism common to mono- and dinuclear iron sites, mono- and dinuclear copper sites, and copper-iron sites. The outline proposals comprise ... 

The electronic spectrum of Fe—O2 in a hemerythrin derivative has been reported. Further references to reactions of iron porphyrins with dioxygen species appear in Section 5.4.3.7.2. 

Table 2 Structural and infrared spectroscopic data for dioxygen species [117] ...

The analogous dioxygen species (IMes)2Pd(02) was isolated for the Pd(IMes)2 complex, confirming the above analysis [78]. But in this case the peroxo complex does not react with CO2. Addition of acetic acid to a toluene solution of the peroxo complex produces a hydroperoxopalladium(II) complex species (IMes)2Pd(OAc)(OOAc). Further protonolysis to yield hydrogen peroxide proceeds quite slowly (Scheme 12). Details are described in another article of this issue by S. Stahl. 

Busca (18b) has evaluated the literature values for infrared bands attributed to coordinated and adsorbed dioxygen species. He concludes that it is very difficult to deduce the nature of the dioxygen coordination from measurements of the frequency shift, Av00, with respect to the stretching frequency of the free molecule. It needs to be stressed that it is also difficult to distinguish between mononuclear and molecular species from measurements of v00, and this can only be achieved by careful interpretation of experiments using 160/180 isotopic mixtures. The absence of such experiments very often accounts for the conflicting attributions in the literature which are discussed in later sections. 

Defined as N = (n - n )/2, where n and n are the numbers of electrons in the bonding and antibonding molecular orbitals, respectively, of the corresponding dioxygen species. e R = alkyl. 

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