Complexes with oxygen

Rhodium complexes with oxygen ligands, not nearly as numerous as those with amine and phosphine complexes, do, however, exist. A variety of compounds are known, iucluding [Rh(ox)3] [18307-26-1], [Rh(acac)3] [14284-92-5], the hexaaqua ion [Rh(OH2)3] [16920-31 -3], and Schiff base complexes. Soluble rhodium sulfate, Rh2(804 )3-a H2 0, exists iu a yellow form [15274-75-6], which probably coutaius [Rh(H20)3], and a red form [15274-78-9], which contains coordinated sulfate (125). The stmcture of the soluble nitrate [Rh(N03)3 2H20 [10139-58-9] is also complex (126). Another... 

Coordination Complexes. The abiUty of the various oxidation states of Pu to form complex ions with simple hard ligands, such as oxygen, is, in order of decreasing stabiUty, Pu + > PuO " > Pu + > PuO Thus, Pu(Ill) forms relatively weak complexes with fluoride, chloride, nitrate, and sulfate (105), and stronger complexes with oxygen ligands (Lewis-base donors) such as carbonate, oxalate, and polycarboxylates, eg, citrate, and ethylenediaminetetraacetic acid (106). The complexation behavior of Pu(Ill) is quite similar to that of the light lanthanide(Ill) ions, particularly to Nd(Ill)... 

Complexes with oxygen-donor ligands can be isolated as solids. The hydrated salts, Hg2(N03)2 2 H20 and Hg2(C104)2 -4 H20 both contain the aquo complex ion I ... 

Alkyliron(lll) porphyrin complexes are air. sensitive, and when exposed to oxygen under ambient conditions the products are the very stable iron(IIl) /t-oxo dimers, [Fe(Por)]20. A more careful investigation revealed that the reaction of the alkyl complexes with oxygen proceeds via insertion of O2 into the Fe—C bond. " When a solution of Fe(Por)R (R = Me, Et, i-Pr) is exposed to O2 at —70 C, the characteristic H NMR spectrum of the low spin iron alkyl complex disappears and is replaced by a new, high spin species. The same species can be generated from the reaction of an alkyl hydroperoxide with Fe(Por)OH, and is formulated as... 

Platinum(II) Complexes with Oxygen-donor Ligands 709... 

S.4.4 PlatiiHim(II) Complexes with Oxygen-donor Ligands 6.5.4.4.1 Aqua, hydroxo, and oxo ligands... 

Silver(I) complexes with oxygen donor ligands have been prepared with three different types of ligands /3-diketonates, carboxylates, and crown ethers. 

With respect to calculations of the electronic structure of molecular clusters and their complexes with oxygen, the PM 3 program of the computer-driven system called MOPAC was used. 

In order to explain the catalytic activity of PANI, we have modeled the electronic structure of doped molecular PANI clusters and its adsorption complexes with oxygen and hydrogen. The geometric and electronic... 

In order to study the possible reasons and mechanisms of the catalytic activity of conducting polymers (CP), the electronic structure of some molecular CPs clusters and its adsorption complexes with oxygen were modeled [6], In the CP-O2 complex, the CP surface is an electron density donor. For example, in the case of PANI, the bond orders in adsorbed O2 molecules decrease by about 30%, and the bond lengths L increase by about 24%. Thus, the adsorbed O2 molecules have a fairly high degree of activation and can readily interact with the protons. 

Thus, Cr3 + and Co3 + belong to dass A because they form more stable complexes with oxygen as the donor atom than when sulfur is the donor atom. On the other hand, Ag+ and Pt2+ belong to dass B because they form more stable complexes with P or S as the donor atom than with N or O as the donor atom. 

High-Nuclearity Paramagnetic 3d- Metal Complexes with Oxygen- and Nitrogen-Donor Ligands Richard E. P. Winpenny... 

FeP-02). (b) Optimized structure of the full heme b molecule complexed with oxygen (heme-02). 

Onodera, K., Furusawa, C.-I., Kojima, M., Tsuchiya, M., Aihara, S., Akaba, R., Sakuragi, H. and Tokumaru, K. (1985). Mechanistic considerations on photoreaction of organic compounds via excitation of contact charge transfer complexes with oxygen. 

Takeya, H., Kuriyama, Y. and Kojima, M. (1998). Photooxygenation of stilbenes in zeolite by excitation of their contact charge transfer complexes with oxygen. Tetrahedron Lett. 39, 5967-5970... 

The reaction of binuclear copper complexes with oxygen as models for tyrosinase activity was also markedly accelerated by applying pressure (106408 ). Tyrosinase is a dinuclear copper protein which catalyses the hydroxylation of phenols. This reaction was first successfully modeled by Karlin and co-workers (109), who found that an intramolecular hydroxylation occurred when the binuclear Cu(I) complex of XYL-H was treated with oxygen (Scheme 5). 

In a recent paper a detailed mechanistic study of this reaction was presented (108). The first step is the reversible binding of oxygen by forming a u-peroxo species. This intermediate reacts further via an irreversible step to the hydroxylated product. The kinetic measurements at high pressure were performed at -20°C, since at room temperature no peroxo intermediate can be observed. The forward reaction of the Cu(I) complex with oxygen is characterized by a strongly... 

THE REACTIVITY OF TRANSITION METAL COMPLEXES WITH OXYGEN... 

Complexes with Oxygen and Other Donor Atoms. The crystal structure of the 4-phenylpyridine adduct of [VO(acac)2] has shown that the molecule adopts an approximately cis-octahedral structure (37) with a V=0 bond length of 158(1) pm. ... 

---