Tris complex, oxidation

Samarium, tris(triphenylphosphine oxide)bis-(diethyldithiophosphato)-structure, 1,78 Samarium complexes dipositive oxidation state hydrated ions, 3, 1109 Samarium(III) complexes salicylic acid crystal structure, 2, 481 Sampsonite, 3, 265... 

Abdou, H. (2006) PhD. Thesis New Chemistry with Gold-Nitrogen Complexes Synthesis and Characterization of Tetra-, Tri-, and Dinuclear Gold(I) Amidinate Complexes. Oxidative-Addition to the Dinuclear Gold (I) Amidinate, A M University, Texas. 

In a very special system, the photoelectrochemical regeneration of NAD(P)+ has been performed and applied to the oxidation of the model system cyclohexanol using the enzymes HLADH and TBADH. In this case, tris(2,2 -bipyridyl)ruthenium(II) is photochemically excited by visible light [43]. The excited Ru(II) complex acts as electron donor for AT,AT -dimethyl-4,4 -bipyridinium sulfate (MV2+) forming tris(2,2 -bipyridyl)ruthenium(III) and the MV-cation radical. The Ru(III) complex oxidizes NAD(P)H effectively thus... 

The possibility of generating a 1 1 complex of aluminium by tethering together three aryloxide moieties has been explored. Synthesis [165] of the tripodal, polydentate ligand N[2-[(CH2)2N(H)CH2]-Ar 3 (Ar = 4-chlor-ophenol) allows subsequent treatment with one equivalent of (H20)9 A1(C104)3 in the presence of excess (H20)3 NaOAc to afford a tris(phen-oxide) complex [166]. More recently, the formation of Al-N(H) interactions has been precluded in the tris(2-hydroxybenzoyl)-2-aminoethylamine and tris(2-hydroxy-3-methoxybenzoyl)-2-aminoethylamine trianion complexes... 

Four-membered ring complexes with cadmium are useful as precursors for the preparation of tri- -octylphosphine oxide (TOPO) capped materials. Thus, compounds 95 were efficient precursors to CdSe nanoparticles on thermolysis in TOPO C1996AM161, 1997CM523, 1998CC833, 1998CC1849, 1999CC2235>. 

Epoxide-carbaayl rearrangement. Lithium bromide effects facile rearrangement of epoxides to aldehydes and/or ketones in benzene solution. The salt is insoluble in benzene but addition of 1 mole of HMPT or tri- -bulylphosphine oxide per mole of lithium bromide affords a soluble complex which effects the epoxide rearrangement. Evidence suggests a mechanism involving the salt of the bromohydrin as an intermediate. 

The most comprehensive studies of the effect of acidity on potentials are those of Schilt 617, 618), where media up to 12 M in sulfuric acid were used. For M = Fe, Ru, or Os, the oxidation-reduction potential for M(bipy) +/M(bipy) + becomes less negative as the medium becomes more acid, while the converse is true for [M(bipy)2(CN)3]/[M(bipy)2(CN)2]. These results are interpreted as showing the formation of stable ion-pairs derived from the tris complexes and acid anions the CN groups in the mixed M(II) but not M(III) complexes may behave as bases yielding mono- and diprotonated species. 

There are few reported data for the rates of electron transfer between the large complexes of these ligands. The rates are very large, and for the iron group metals NMR studies only allow a lower limit of 10 1 mole sec to be set (200, 224, 473, 474). The exchange between the tris complexes of Co(II) and Co(III) is found to catalyze ligand exchange for Co(III) (230) it has also been studied in nonaqueous media (504). Because of their convenient analytical properties, however, bipyridyl and phenanthroline complexes have been extensively examined in their oxidation reduction reactions. 

Bipyridine is a strong field ligand that forms relatively stable complexes, with the inherent M—N bond strength enhanced by the chelate effect. These factors favor the formation of 4-coordinate bis and 6-coordinate tris complexes. The tris complexes of the first row transition metals in normal oxidation states (+2 or +3) are best prepared by the reaction of a suitable metal salt with an excess of bpy in water, methanol, or other organic solvent. The solid complexes can be obtained by crystallization or by the precipitation of the perchlorate, hexafluorophosphate, tetrafluoroborate, or other salts. Because bpy is a strong field ligand, the lower oxidation states tend to be favored, and reduction of M(III) complexes can occur in these preparations. The M(III) complexes are usually readily obtained by the chemical, aerobic, or electrochemical oxidation of the M(II) species. 

Addition of tri- -octylphosphine oxide (TOPO), a proposed synergist, to the system works to improve the uptake of both actinide ions. Two plausible complexation stoichiometries have been reported for the synergistic effect of TOPO, suggesting the formation of two different extracted species (see Equations (56) and (57)) ... 

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