Vanadium complexes mononuclear

Two separate publications (125, 126) described the synthesis of a number of carbonyl complexes of vanadium. The mononuclear species V(CO) , n = 1-6, have all been identified by using CO matrix-dilution experiments and mixed CO- CO isotope experiments while main-... 

Valinomycin metal complexes, 969 Vanadium complexes acetylacetone exchange reactions, 380 1,4-diaza-l,3-butadiene, 209 dioxygen mononuclear, 321 hydrazido(2-), 148 hydroxamic adds, 506 phthalocyanines, 865 polypyrazolylborates, 248 porphyrins, 824 dioxygen adducts, 325... 

The complexes derived from simple monodentate carboxylates are not stable, and only one mononuclear complex with a sterically hindered carboxylate has been successfully isolated, [VCKCbC Bujs] (13).103 Attempts to prepare carboxylates in organic solvents often led to the formation of oligomeric cluster compounds with a variety of interesting structural types.103 In aqueous solutions, these vanadium complexes appear to contain six-coordinate vanadium.60,104 Even carbonate has been found to form a weak vanadiumtV) complex in solution.105... 

New complexes containing azo- and hydrazinato-derivatized Schiff base ligands298 375 continue to be used for the analytical determination of vanadium.376 The vanadium complex was characterized for the Schiff base derived from the condensation reaction of benzoyl acetone and Girard s reagent P.377 Azophenolates of mononuclear and mixed valence dinuclear species have been reported.378 Naphthanol- or quinolinol-derivatized ligands prefer to chelate iron over vanadium.379... 

Coordination compounds of vanadium(V) also catalyze peroxidative halogenation reactions where the reactive oxidant is a monoperoxo complex of a mononuclear vanadium compound (Figure 6) [11,22,92-95,99]. 

Holmes, S. and CJ. Carrano. 1991. Models for the binding site in bromoperoxidase Mononuclear vanadium(V) phenolate complexes of the hydridotris(3,5-dimethylpyra-zolyl)borate ligand. Inorg. Chem. 30 1231-1235. 

Vanadium(V) alkoxides have been known since 1913,69 and in Table 2 we show some of the known alkoxides, the parent alcohol, and the nature of the complex in organic solvents and in aqueous solution. Alkoxides have been prepared from methanol, ethanol, isopropanol, t-butanol, silsequioxanes, cyclopentanol, cyclohexanol, norborneol, adamantanol, phenol, and other alcohols (see Table 2).70- 0 The simple complexes associate in organic solvents and dimerization in the presence of alkoxide is observed with the isopropanol complex.70 The more sterically hindred alcohols are less reactive and do not hydrolyze completely in the presence of small amounts of water.73 The first simple alkoxide to be structurally characterized was the methoxide complex (14) and the vanadium was found to be a six-coordinate dinuclear species however, the structure of this compound did not refine very well.91 This was the first report of the diamond core V—O—V—0 unit, albeit associated with two six-coordinate vanadium atoms. The diamond core V—O—V—O (11), which has since then been found to be a typical structural unit for these complexes, was distinctly asymmetric revealing a difference in the interactions between the two mononuclear parts of the molecule. The first monodentate alkoxide found to contain... 

A mononuclear complex with formate ligands has been structurally characterized (97).478 Each unit of K2[V0(HC02)4] has the vanadium in a pseudo-octahedral geometry, with the coordination of an adjacent molecule s free carbonyl (C=0) group serving as the sixth ligand.478 The... 

Mononuclear Viv complexes of substituted hydroxamates have been characterized with 1,10-phenanthroline or 2,2 -bipyridine as supporting ligands. A seven-coordinate vanadium atom was proposed to exist in these complexes, although a six-coordinate complex may be more likely.652 A range of hydroxamate-containing complexes have been prepared and were subsequently found to facilitate transport of Viv into cells.653... 

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