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Thallium complexes perchlorates

Thallium (III) perchlorate is obtained from T1CI3 + AgC104, or by the anodic oxidation of T1C104. Complexing by perchlorate appears very unlikely and the same applies to chlorate, bromate or iodate.1-3... [Pg.173]

Intramolecular electron transfer in a stepwise manner from the amine substrate to die silver(III) center in a 1 2 complex, [Ag(OH)4] -iV,/V-dimcthylanilinc, has been observed.44 The kinetics of oxidation of some aliphatic, heterocyclic, and aromatic aldehydes towards bis(dihydrogentellurato)cuprate(III) and argentate(III) in alkaline medium have been studied.45 A negative salt effect was observed in the oxidation of aminoacetic acid by diperiodatocuprate(III) complex in alkaline medium.46 The oxidation of glutamic acid by thallium(III) perchlorate is catalysed by Ru(M), Os(III), and Nd(III) in a free radical mechanism and the rate is inversely dependent on [H+] concentration.47... [Pg.183]

Upon addition of perchlorate ions to the acetonitrile solutions, the salt [(MeCN)2ln Mn(C0)j 2]C104 can be isolated. This will react with pyridine or phenanthroline to yield [L2ln Mn(C0)5 2]C104 (L = py or phen). The compounds R4N[X4 In Mn(CO)5)J (n = 1—3 R = Me, X = Cl R == Et, X = Br) have also been prepared. Thus this work shows that as well as influencing the amount of dissociation of metal-metal bonded complexes, the nature of the solvent also determines the mode of ionization. The complex [TljMnlCOljlj] can be conveniently prepared from thallium(i) salts and [Na(Mn(CO)g ]. ... [Pg.180]

Cationic complexes of Tl3+ with oxygen donors are known, and can be regarded as substitution products of [T1(C)H2)6]3+ (c/. Section 25.2.8.3.1). The DMSO product has been characterized with various anions,403 and there seems no reason to suppose that similar compounds cannot be prepared with donor ligands which are resistant to oxidation. The cation [Tl(pyNO)8]3+ (prepared as the perchlorate) may be an indication that eight-coordinate compounds are also accessible in thallium(III) chemistry.404... [Pg.174]

Adducts of triazoles with transition metal salts are usually prepared by direct reactions between the two components involved and frequently precipitate or crystallize spontaneously from the reaction mixture (55,172,194, 202). Complexes containing triazolate anions can usually be obtained from the corresponding transition metal halide, carboxylate, nitrate, or perchlorate complex and an alkali metal (146, 147, 172) or thallium(I) triazolate salt (33). Other routes to triazolate complexes include the direct reactions of metal halides with triazoles in the presence of a base (201) and the treatment of triazole/metal halide... [Pg.174]

Thallium(I) halides are predominantly ionic, although there is a tendency toward increasing covalent character in the series of compounds TlCl (17%), TlBr (20%), and TII (28%). This increased degree of covalency results in decreased solubility for example, TIF is soluble in water whilst the other Tl halides are only sparingly soluble. The thallium(I) halides are classical examples of incompletely dissociated 1 1 electrolytes. The stability of halide complexes of Tl is low and follows the order TIF < TlCl < TlBr < TII, where for the series of halides, Kx = -, 0.8, 2.1, 5.0 and Ki = -, 0.2, 0.7, 1.5 respectively. The fluoride ion F is preferred to perchlorate as a noncomplexing counterion. Claims have been made for T1X species with n = 3 and 4 however, the formation of complexes in aqueous solution with n > 2 seems unlikely. [Pg.4827]

Sutton (666) and Kul ba (458-460) have prepared a number of bipyridyl and phenanthroline complexes of various thallium(III) salts those with nitrate and perchlorate are generally bis-chelate compounds, whereas the halides give compounds of stoichiometry TIX3L. Stability constants have been reported for some of the complexes (457). Other mixed ligand species containing ethylenediamine (461) and oxalate (456) and salts containing both bipyridyl and phenanthroline coordinated to the same thallium(III) ion (456) are also claimed. [Pg.177]

Diarylacetylenes are converted in 55-90% yields into a-diketones by refluxing for 2-7 h with thallium trinitrate in glyme solutions containing perchloric acid [413. Other oxidants capable of achieving the same oxidation are ozone [84], selenium dioxide [509], zinc dichromate [660], molybdenum peroxo complex with HMPA [534], potassium permanganate in buffered solutions [848, 856, 864,1117], zinc permanganate [898], osmium tetroxide with potassium chlorate [717], ruthenium tetroxide and sodium hypochlorite or periodate [938], dimethyl sulfoxide and iV-bromosuccin-imide [997], and iodosobenzene in the presence of a ruthenium catalyst [787] (equation 143). [Pg.91]

The most substantial investigation of thallium(II) species in aqueous solution is that of Dodson and Schwarz, who studied equilibria and kinetics of Tl(II)-Cr complexes (77). On the basis of some (reasonable) assumptions, they have calculated the stepwise stability constants K for the three T1C1 " complexes, n = 1,2,3, in 1M HCIO4 and estimated = 1 from the ratios between the stability constants K, for Tfi Cl " and TT C1 ". The absorption spectra of the individual Tl(II) chloride complexes have been derived from their stability constants in combination with the experimental spectra recorded for solutions with varying composition. Absorption maxima were found at 263 and 342 nm for TlCl, at 280 and 342 nm for TICI2, and at 304 and 362 nm for TlCla". An interesting observation was the 10-fold increase of the extinction coefficient (at —340 nm) of the Tl(II) solution in 1 M perchloric acid upon addition of a small amount of chloride ion ([Cl ] = 10 M) (77). [Pg.9]

Although the redox potentials favour electron transfer between cerium(iv) and thallium(i), the reaction is very slow. Catalysis by osmium(vm) has, however, been observed in both sulphate and perchloric acid media. In the latter system, although perchlorate complexing is not completely ruled out, the reactive species is considered to be the hydrolysed cerium(iv) ion, the mechanism... [Pg.30]

The oxidation of methylcyclobutene by Hg" and Pd" in IM perchloric and hydrochloric acids has been described, and whereas the thallium(m) reaction involves an intermediate complex, the corresponding oxomercurial species is relatively stable. The products of oxidation and isomerization of phenylcyclopropane by palladium(n) have been reported. In 2 1 glyme-H20 (v/v) using PdCU " as oxidant, propiophenone and phenylacetone are the major products, the reaction proceeding via an oxypalladium complex,... [Pg.65]

Concerning the determination of surfactants, in 1997 Vytras s group demrai-strated that carbon paste-based electrodes could also be used as potentiometric sensors to monitor titrations of surfactants.When compared to PVC and CW electrodes, CPEs had the advantages of very low Ohmic resistance, very short response time in addition to the ease of fabrication and regeneration as well as long functional lifetime. Jezkova et al. used perchlorate and fluoroborate ion-selective carbon paste electrodes for both direct potentiometric measurements and potentiometric titration of perchlorate or fluoroborate with 0.1 M CPC. The electrodes had a rapid response, low Ohmic resistance, and limits of detections and selectivity similar to the limits of commercial membrane electrodes. A carbon paste electrode incorporated with the ion association of CPC-thallium halo complexes was applied as indicator electrode with the potentiometric titration of surfactants. ... [Pg.209]


See other pages where Thallium complexes perchlorates is mentioned: [Pg.75]    [Pg.176]    [Pg.153]    [Pg.241]    [Pg.232]    [Pg.168]    [Pg.617]    [Pg.429]    [Pg.289]    [Pg.68]    [Pg.133]    [Pg.5]    [Pg.11]    [Pg.27]    [Pg.28]    [Pg.32]    [Pg.37]    [Pg.241]    [Pg.311]    [Pg.499]    [Pg.568]    [Pg.2007]    [Pg.183]    [Pg.436]    [Pg.264]    [Pg.145]    [Pg.69]    [Pg.256]    [Pg.22]    [Pg.109]    [Pg.39]   
See also in sourсe #XX -- [ Pg.173 ]

See also in sourсe #XX -- [ Pg.3 , Pg.173 ]




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