8-hydroxyquinolinato complex

If the anion is bidentate then bidentate neutral ligands form [RhX(LL)] complexes. Strangely, only one example of such a complex is known. The orange 5-methyl-8-hydroxyquinolinato complex... 

CpTiCl3 reacts with 5-chloro-8-hydroxyquinoline (oxH) in acetonitrile to give the 8-hydroxyquinolinato complex CpTiCl(ox)2. Its molecular structure has been determined by X-ray diffraction which shows a cis-N and the trans-O configuration.998... 

Since, according to Eq. 17.14, M2+ must compete with 2H+ for Q, we can set the pH low enough to ensure that only copper(II) forms major amounts of an uncharged di(hydroxyquinolinato) complex, which can then be extracted selectively into, say, chloroform. When this is complete, the pH could be increased enough to permit selective extraction of NiQ2, etc. The metal ions can be stripped from the extractant by the reverse process, i.e., by equilibration with sufficiently concentrated aqueous acid. 

Fluoride can be determined by means of an iron(iii) thiocyanato complex extracted into isobutylketone. Iron is extracted back into the aqueous phase with the fluoride sample solution. The atomic absorption signal of iron is directly proportional to the concentration of fluoride (0.5-6 ju,g F ml ). EDTA can be determined by a similar technique. Copper is first extracted as the hydroxyquinolinato complex into isobutylketone, and then extracted back into the aqueous solution with the EDTA sample solution. In these methods the analyte anion must form a more stable complex compound with the metal ion than the ligand used for the first solvent extraction. These kind of... 

Complexes of 8-hydroxyquinoline and chromium(III) have been known for many years.1139 Complexes have been mercurated and the deuterated quinoline isolated.1139 The bromination of chelated 8-hydroxyquinoline proceeds about thirty-five times faster than that of the free ligand.1140 Tris(8-hydroxyquinolinato)chromium(III) absorbs large amounts of hydrochloric, hydrobromic and hydrofluoric acids. Chemical reaction with the complex was considered a more likely explanation than solid solution or clathrate formation, even though more than one mole of acid was absorbed per mole of complex.1141... 

Zinc complexes are important as additives for rubber polymers. Dithiocarbamate complexes are most commonly used here, but bis(8-hydroxyquinolinato)zinc inhibits the thermal decomposition of poly[(trifluoroethoxy)(octafluoropentoxy)phosphazene]. The zinc is thought to complex residual P—OH groups in the polymer chain, which would otherwise lead to rearrangement and chain scission.126... 

Vanadium-sulphur ligand complexes have been studied as models of biological vanadium systems (see Vol. 5, p. 42). Tris(diethyldithiocarbamato)vanadium(iii) is more easily reduced and oxidized than its 8-hydroxyquinolinato analogue. It is suggested that this is a reflection of the increased electron density and/or electron mobility in the sulphur ligand. 

The authors did not report the thermal stability of the copper(II) complex. However, they mention, that it is noteworthy that picryl azide reacts with a variety of olefins, norbomene, pinene, cyclopentene, cyclooctene, and others, with exceptional ease . The fact, that the copper(II) does not decompose this organoazide can clearly be attributed to the efficient shielding of the copper(ll) centre by the two 8-hydroxyquinolinato ligands. 

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