8-hydroxyquinoline-5-sulphonic acid

SWV has been applied to study electrode reactions of miscellaneous species capable to form insoluble salts with the mercury electrode such as iodide [141,142], dimethoate pesticide [143], sulphide [133,144], arsenic [145,146], cysteine [134, 147,148], glutathione [149], ferron (7-iodo-8-hydroxyquinolin-5-sulphonic acid) [150], 6-propyl-2-thiouracil (PTU) [136], 5-fluorouracil (FU) [151], 5-azauracil (AU) [138], 2-thiouracil (TU) [138], xanthine and xanthosine [152], and seleninm (IV) [153]. Verification of the theory has been performed by experiments at a mercury electrode with sulphide ions [133] and TU [138] for the simple first-order reaction, cystine [134] and AU [138] for the second-order reaction, FU for the first-order reaction with adsorption of the ligand [151], and PTU for the second-order reaction with adsorption of the ligand [137]. Figure 2.90 shows typical cathodic stripping voltammograms of TU and PTU on a mercuiy electrode. The order of the... 

Iodo-8-hydroxyquinoline-5-sulphonic acid (or ferron reagent)... 

Many other reagents have been used for determining iron, e.g., sulphosalieylic acid [106-109], ferron (7-iodo-8-hydroxyquinoline-5-sulphonic acid) (e = 4.0-10 at 610 nm) [110], Tiron [111,115], HTTA [116,117], pyrocatechol [118], phenylfluorone (in presence of Triton X-100 [119], morin (in the presence of a surfactant e = 6.3-10 ) [120-122], Alizarin S (extraction with Aliquat 336 in CHCI3] [123], Purpurin [124,125], salicylates[126,127], 2,2 -diquinoxalyl [128], sulphanilic acid in the presence of a surfactant [129], haematoxylin [130], and hydroxamic acid derivatives [13,14,131,132]. 

Other organic spectrophotometric reagents for Nb include 8-hydroxyquinoline-5-sulphonic acid [75], 5,7-dichloro-8-hydroxyquinoline (e =1.3-10 at 400 nm) [76], 5-chloro-7-iodo-8-hydroxyquinoline [77], Lumogallion [78], and thioglycolic acid [79], Nb has also been determined after extraction of its complex with 3-hydroxyflavone [80] and N-a-phenylstyrylacrylhydroxamic acids [81]. 

In this group the variation of log Kx is similar to (5) for the region from La to Gd. This is followed by an almost linear rise of the log Kj values upto lutetium. Example NT A, 8-hydroxyquinoline-5-sulphonic acid. 

The disodium salt of 7-nitroso-8-hydroxyquinoline-5-sulphonic acid (Na2L) reacts with Cu " to form CuL,H20. Cu(C10 )2 reacts with 10-methyl-isoalloxazine (L) and aqueous formic acid to form [CuL2](C104)2,4H20, the structure of which is shown as (214). The complex serves as a model compound for metal-flavin enzymes and controverts earlier suggestions that... 

No appreciable polymerization occurred in concentrated aqueous solutions of La or Nd hydroxonitrilotriacetates but, with the heavier lanthanides, dimerization, via hydroxo bridges, occurred in dilute solution. A series of mixed ligand chelate complexes was obtained with Ho and Er and 5-sulpho-salicylate (ssa) and edta, iV-hydroxyethylethylenediamine-triacetic acid, 1,2-diaminocyclohexanediamine-tetra-acetic acid (YX i.e. [M(Y)(ssa)], and iminodiacetic acetate, hydroxyethyliminodiacetic acid and nitrilotriacetic acid, [M(Y)(ssa)2] with higher carboxylates, no mixed chelate complexes were produced. In the presence of an excess of hydroxyethylethylenediamine triacetic acid (H3A), [Eu(A)(HA)] was formed. Lanthanum(m) formed 1 1 complexes with nitrilotriacetic acid and 8-hydroxyquinoline, or 2-picolinic acid and 8-hydroxyquinoline-5-sulphonic acid. 

The 1 1 complexes between the lanthanides and edta form stable associates with the anions of 8-hydroxyquinoline-5-sulphonic acid (oxs), iminodiacetic acid (ida), and nitrilotriacetic acid (nta) since the characteristic co-ordination number of the Ln ions is generally greater than six. In Figure 6 the free-energy changes associated with the formation of these... 

Chiniofon, N,F., is a mixture of 7-iodo-8-hydroxyquinoline-5-sulphonic acid, its sodium salt, and sodium bicarbonate. 

Using the above methods, compounds have also been obtained from quinoline-8-sulphonic acid and 8-hydroxyquinoline. 

Hydroxyquinoline derivatives containing sulphonic acid groups, e.g., ferron [a reagent for iron(III), give water-soluble complexes with metal ions. 

Lin and Bear report a pressure-jump investigation of the formation of magnesium oxalate in water. Rate constants and activation parameters are quoted and discussed in terms of the normal mechanism. The vanadyl-tartaric acid and nickel(ii)-8-hydroxyquinoline and -8-hydroxyquinoline-5-sulphonate systems are also reported. An n.m.r. study involving the reaction of with Mn +, Fe +, Co +, and Ni + suggests that the mechanism involves several parallel pathways. ... 

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