Ruthenium complex thallium

In 1971, a preparation of 1 from 2 using thallium cyclopentadienide was reported (I) but the toxicity of thallium and the mass of the reagent needed render this procedure unsuitable for large-scale preparations. An improved method was reported by Bruce et al. (3,4), using cyclopentadiene, ruthenium trichloride hydrate (3), and triphenylphosphine, which gives the desired complex in high yield [Eq. (2)]. The primary advantage of this latter method is formation of the complex in one pot. 

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). 

The trimethylsilylated silicic acids formed in this instance are soluble in conventional organic solvents, and their volatility is sufficiently high for them to be analysed by gas chromatography. Carzo and Hoebbel [411] carried out a comprehensive study of the chromatographic retention of various trimethylsilylated silicic acids on different stationary phases Apiezon L and silicone OV-1 and OV-17. The analysis of metals in the form of volatile complexes continues to attract attention, and have been described for analysing sodium [412], potassium [412], radium [413], caesium [413], barium [414], calcium [414], strontium [415], beryllium [416, 417], magnesium [418], zinc [419, 420], nickel [419], mercury [421], copper [422, 423], silver [424, 425], cadmium [421], indium [426, 427], g ium [428], scandium [217], cobalt [421], thallium [426], hafnium [429, 430], lead [431, 432], titanium [430], vanadium [433], chromium [434-436], manganese [426], iron [437], yttrium [438], platinum [439,440], palladium [439, 441, 442], zirconium [430], molybdenum [443], ruthenium [444], rhodium [445], rare earths [446—449], thorium [221, 450, 451] and uranium [221, 452]. The literature on GC analysis of metal chelates was reviewed by Sokolov [458]. 

The preparation of two cyclo-octatetraene-gold complexes, (ct)AuCl and (cot)-AU2CI4, has been reported. The structures of biscyclo-octatetraenyl complexes of titanium, vanadium, thallium, and uranium, were deduced from their i.r. spectra. Protonation of (p-cyclo-octatetraene) (p-cyclopentadienyl) complexes has been studied. For the ruthenium and osmium complexes protonation occurs on the eight-membered ring to give CgH moiety co-ordinated to the metal atom via both an T -alkyl and an olefin-metal bond. For the cobalt and rhodium complexes a bicyclic cation (287) is produced which undergoes isomerization to the monocyclic (288). ... 

Welz et al. [151] investigated in detail the determination of thallium in marine sediment reference materials, a particularly complex topic, because of the volatility of TlCl, and the various spectral interferences that could be observed in the vicinity of the T1 line (refer to Section 8.2.1). The authors had previously investigated this using direct analysis of solid samples and Zeeman-effect BC [142], however they only succeeded in obtaining reliable results when ruthenium was used as permanent modifier, and a solution of ammonium nitrate was pipetted on top of the solid sample as an additional modifier. Method development turned out to be much easier in HR-CS AAS, and the spectral interference due to the sulfur content of the sediments could be completely removed using least-squares BC (refer to Section 8.2.1). 

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