Dioxygen, complexes

On reaction with 02, the P—Ir-P colinearity is maintained (174.5°), keeping these bulky ligands apart, but the Cl-Ir-C angle closes (to 97.4°) to accommodate the incoming 02 molecule. The geometry of the 02 adduct can be described as distorted octahedral, with Ir, Cl, C and the two O atoms essentially coplanar. As expected as the coordination number increases, there is a general increase in bond length (except for Ir—Cl). 

The S2 group is removed by Hg or R3P, oxidized by periodate to coordinated S20 or SO and methylated by Me3S03F. 

It is essential that reagent grade CHC13 is used in the synthesis as the trace of ethanol stabilizer removes the aryl isocyanate byproduct and prevents it 

The orange thiocarbonyl is air stable (IR i/(C=S) 1332 cm-1) its synthesis proceeds via an isolable C2S5 complex that is desulphurized by refluxing with PPh3 [144]  

The iridium(II) complexes are rarer that those of rhodium(II). Iridium does not seem to form carboxylates Ir2(02CR)4 with the lantern structure complexes analogous to trans-RhX2 (PR3 )2 are not formed with bulky tertiary phosphines, probably because the greater strength of Ir-H bonds leads to IrHX2(PR3)2. 

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AH of the commercial inorganic peroxo compounds except hydrogen peroxide are described herein, as are those commercial organic oxidation reactions that are beheved to proceed via inorganic peroxo intermediates. Ozonides and superoxides are also included, but not the dioxygen complexes of the transition metals. 

Reversible formation of a dioxygen complex by direct reaction of O2 with trani-[Ir(CO)Cl(PPh3)2] discovered by L. Vaska. 

Chemistry of transition metal complexes supported by hydrotris(pyrazolyl) borates and chemistry of dioxygen complexes based on these ligands 99YGK619. 

Figure 3.18 Metal-dioxygen bonding in platinum-dioxygen complexes.

Bond lengths (Continued) carbonyl complexes dioxygen complexes disulphur complexes dithiocarbamates Mlerene complexes halide complexes halides... 

Electronic spectra of metal-dioxygen complexes. A. B. P. Lever and H. B. Gray, Acc. Chem. Res.,... 

Formation and stabilities of cobalt dioxygen complexes in aqueous solution. A. E. Martell, Acc. Chem. Res., 1982,15,155-162 (68). 

Thermodynamics of oxygen binding in natural and synthetic dioxygen complexes. E. C. Nieder-hoffer, J. H. Timmons and A. E. Martell, Chem. Rev., 1984, 84,137-203 (599). 

The structure and reactivity of dioxygen complexes of the transition metals, M. H. Gubelmann and A. F. Williams, Struct. Bonding (Berlin), 1983,55,1-65 (529). 

A number of investigations of the copper-group oxides and dioxygen complexes have been reported. The electronic spectra of CuO, AgO, and AuO were recorded in rare-gas matrices (9), and it was found that the three oxides could be formed effectively by cocondensation of the metal atoms with a dilute, oxygen matrix, followed by near-ultraviolet excitation. The effective wavelengths for CuO or AgO formation were X > 300 nm and for AuO was X > 200 nm. In addition, the laser fluorescence spectrum of CuO in solid Ar has been recorded (97). 

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