Diphenylthiocarbazone complexation

The nature of the donor atoms in the chelating agent. Ligands which contain donor atoms of the soft-base type form their most stable complexes with the relatively small group of Class B metal ions (i.e. soft acids) and are thus more selective reagents. This is illustrated by the reagent diphenylthiocarbazone (dithizone) used for the solvent extraction of metal ions such as Pd2+, Ag+, Hg2+, Cu2+, Bi3+, Pb2+, and Zn2 +. ... 

Diphenylcarbazide as adsorption indicator, 358 as colorimetric reagent, 687 Diphenylthiocarbazone see Dithizone Direct reading emission spectrometer 775 Dispensers (liquid) 84 Displacement titrations 278 borate ion with a strong acid, 278 carbonate ion with a strong acid, 278 choice of indicators for, 279, 280 Dissociation (ionisation) constant 23, 31 calculations involving, 34 D. of for a complex ion, (v) 602 for an indicator, (s) 718 of polyprotic acids, 33 values for acids and bases in water, (T) 832 true or thermodynamic, 23 Distribution coefficient 162, 195 and per cent extraction, 165 Distribution ratio 162 Dithiol 693, 695, 697 Dithizone 171, 178... 

An interesting method (88) for the separation of trace amounts of polonium makes use of the volatility of some, as yet unidentified, organic compounds. Polonium complexes with diphenylearbazonc, diphenylear-bazide and diphenylthiocarbazone sublime below 100°C under atmospheric pressure and those with thiourea, 8-hydroxyquinoline, s-diphenylthiourea, thioseinicarbazide and other related compounds sublime below 160°C under the same conditions. Thus trace polonium has been separated from dilute nitric acid in the presence of diphenyl carbazide by steam distillation. 

Dithizone (diphenylthiocarbazone) is a green compound that is soluble in nonpolar organic solvents and insoluble in water below pH 7. It forms red, hydrophobic complexes with most di- and trivalent metal ions. 

Methylamino-5-(l-methylalIylamino)-l,3,4-thiadiazoIe is an oxidation product of methallibure, a veterinary oestrus regulator. Separation can be achieved by chromatography on alkylated polydextran gel and elution with mixed organic solvents. Metal salts can be removed by complexation with diphenylthiocarbazone (70JPS835). 

Diphenylthiocarbazone ( dithizone ) forms intensely colored complexes with, for example, Mn, Fe, Co, Ni, Cu, Zn, Pd, Ag, Cd, Pt, Au, and Hg, which are soluble in CCLi and CHCI3, a property which facilitates then-separation and individual determination.Solutions ofmost metal dithizonates in organic solvents have the interesting property of being photochromic (see Photochromism), and the relatively long half-life of the photoexcited mercury(II) dithizonate complexes (ti/2 ca. 1 min) has facilitated then-investigation by conventional specttoscopic techniques. ... 

Reactions were also monitored by SERS. Yamada et discussed the reaction of rose bengal adsorbed on a ZnO electrode. This is an example of the use of the resonance enhancement to gain enough sensitivity. Billmann et followed the chemisorption of cyanide on silver, and detected the formation of the various cyanides on the surface. Similarly, Loo investigated halide complexes on a gold electrode. Pemberton and Buck " used SERS to see the adsorption of diphenylthiocarbazone and its oxidation into... 

Topics, which have formed the subjects of reviews this year, include the luminescence kinetics of metal complexes in solution, photochemical rearrangements of co-ordination compounds, photochromic complexes of heavy metals with diphenylthiocarbazone derivatives, the photochemistry of actinides, actinide separation processes, and light-induced electron-transfer reactions in solution and organized assemblies. A discussion has also appeared on assigning excited states in inorganic photochemistry. ... 

SUB/COR] Subbaraman, P. R., Cordes, S. M., Preiser, H., Effect of auxiliary complexing agents on the rate of extraction of zinc(Il) and nickel(ll) with diphenylthiocarbazone. Anal. Chem., 41, (1969), 1878-1880. Cited on pages 234, 338. 

Diphenylthiocarbazone (dithizone) test dithizone forms complexes with a number of metal ions, which can be extracted with chloroform. The zinc complex, formed in neutral, alkaline or acetic acid solutions, is red ... 

Diphenylthiocarbazone (dithizone) (see page 285) forms insoluble colored inner complex salts with a number of heavy metals. These products are... 

Colorimetric methods based on the reaction of lead with diphenylthiocarbazone to form a red complex. 

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