Complexation hydroxamic adds

The known complexes, MIVL4 (Table 43), precipitate from aqueous solutions of actinide(IV) compounds on addition of the ligand. Somewhat surprisingly, one hydroxamic add, (PhCO)NHOH, behaves as a neutral ligand, and the complex Th(N03)4-2(PhC0)NH0H... 

The complexing capacity of hydroxamic acids was predicted by Werner in 1908, who also indicated the metals most likely to form stable complexes.288 Since then, the formation of poorly soluble and intensely coloured hydroxamates has been used for analytical determinations for a number of metal ions, such as Fe3+, Mos+, Vs+ etc. A recent general review of transition metal complexes of hydroxamic adds included the few known examples of silver(I) complexes.289... 

The preference of hydroxamic acids to form metal complexes through the hydroxamide functional group (1) and not through the hydroxyoxime structure (2) is confirmed by IR,27,28 UV,29 ESR30 and NMR28 spectral studies. Hydroxamic adds bind metal ions to form complexes with structure (3) rather than structure (4), for which evidence has been claimed31 in one case only. 

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... 

Narula and Gupta have measured the thermodynamic stepwise stability constants for the formation of complexes of dialkyltin(TV) ions, R2Sn " (R = Me or Bu ), with hydroxamic adds, RCONHOH (R = Ph, Me2CH, Me) potentiometrically in 75% dioxane-water media. This has been followed by determination of formation constant of iV-arylhydroxamic adds-dialkyltin(IV) ions. Das et have described the synthesis of a munber of diorganobis(hydroxamato)tin(IV)... 

Dutta and Satapathi have described the synthesis of a variety of phenylmercury(II) complexes with benzo-, p-chlorobenzo-, picolino-, quinolino- and quinoline-8-hydroxamic adds and characterized them by their IR spectra and conductivity measurements. 

Hydrosulfido complexes, 517 bonding, 519 reactivity, 519 structures, 519 synthesis, 518 types, 518 Hydroxamates metal complexes, 505-508 Hydroxamic add, Ai-methyl-metal complexes, 507 Hydroxamic add, phenyl-metal complexes stability, 506 Hydroxamic acids... 

Hydroxylamine, O-acetyl-N-benzoyl-At-phenyl-hydroxamic adds from, 506 Hydroxylamine ligands, 101 Hydrozirconation, 342 Hypoxanthines metal complexes, 93... 

Molybdenum(VI) complexes citric acid, 476 IR spectra, 469 guanidine, 283 hydroxamic adds, 506 maleic add, 475 conformation, 467 crystal structure, 476 tartaric add, 479 NMR, 468... 

In the next step, the test solution is cooled and acidified with dilute hydrochloric acid R. Add 0.2 ml of ferric chloride solution R1 diluted ten times and a bluish-red or red color is produced. The product responsible for the color is a complex of iron(III) hydroxamates (Figure 3.18.4). 

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