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Zusammenfassung Eine gravimetrische Methode zur Bestimmung von Quecksilber(I)-ionen mit Kaliumhydrogenphthalat wurde ausgearbeitet. Bei Konzentrationen von 0,1–0,2 g HgI/100 ml sind die Analysenergebnisse gut reproduzierbar. Die mittleren Abweichungen liegen zwischen –0,1 und –0,2%. Die Bestimmung wird durch Ag+, Pb2+, Hg2+, Bi3+, Fe3+ sowie Anionen, die mit Quecksilber(I) unlösliche Niederschläge bilden, gestört.
Summary A gravimetric method for the determination of mercury(I) ions by means of o-phthalate is described. For concentrations of 0.1 to 0.2 g HgI/100 ml well reproducible results are obtained. The mean deviations of the single determinations vary between –0.1 and –0.2%. Ag+, Pb2+, Hg2+, Bi3+, Fe3+ and anions forming sparingly soluble precipitates with mercurous ions interfere with the determination.
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Preparation and Reactions of Methylene-bridged Phosphorus(III)-Phosphorus(V) Compounds The synthesis of methylene-bridged diphosphorus compounds of the type Y2PCH2P(S)X2 (with Y = F, Cl, OPri, NMe2, Ph) is reported. Reactions of these compounds with bicycloheptadiene-metaltetracarbonyls to form complexes of the type (L? L′)M(CO)4 and (L? L′)2M(CO)4, respectively, as well as some oxidation reactions and the conversion of the phosphine F2PCH2P(S)F2 to the cyclotetraphosphine [PCH2P(S)F2]4 are described.  相似文献   

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Trifluoromethylation of AuCl3 by using the Me3SiCF3/CsF system in THF and in the presence of [PPh4]Br proceeds with partial reduction, yielding a mixture of [PPh4][AuI(CF3)2] ( 1′ ) and [PPh4][AuIII(CF3)4] ( 2′ ) that can be adequately separated. An efficient method for the high‐yield synthesis of 1′ is also described. The molecular geometries of the homoleptic anions [AuI(CF3)2]? and [AuIII(CF3)4]? in their salts 1′ and [NBu4][AuIII(CF3)4] ( 2 ) have been established by X‐ray diffraction methods. Compound 1′ oxidatively adds halogens, X2, furnishing [PPh4][AuIII(CF3)2X2] (X=Cl ( 3 ), Br ( 4 ), I ( 5 )), which are assigned a trans stereochemistry. Attempts to activate C? F bonds in the gold(III) derivative 2′ by reaction with Lewis acids under different conditions either failed or only gave complex mixtures. On the other hand, treatment of the gold(I) derivative 1′ with BF3?OEt2 under mild conditions cleanly afforded the carbonyl derivative [AuI(CF3)(CO)] ( 6 ), which can be isolated as an extremely moisture‐sensitive light yellow crystalline solid. In the solid state, each linear F3C‐Au‐CO molecule weakly interacts with three symmetry‐related neighbors yielding an extended 3D network of aurophilic interactions (Au???Au=345.9(1) pm). The high $\tilde \nu $ CO value (2194 cm?1 in the solid state and 2180 cm?1 in CH2Cl2 solution) denotes that CO is acting as a mainly σ‐donor ligand and confirms the role of the CF3 group as an electron‐withdrawing ligand in organometallic chemistry. Compound 6 can be considered as a convenient synthon of the “AuI(CF3)” fragment, as it reacts with a number of neutral ligands L, giving rise to the corresponding [AuI(CF3)(L)] compounds (L=CNtBu ( 7 ), NCMe ( 8 ), py ( 9 ), tht ( 10 )).  相似文献   

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Reaction of AuCl and Au(CO)Cl with pyridyl-, thiazolyl- and imidazolyl-silanes yields the gold(I) chloride complexes of these heterocycles. The Si-C(heterocycle) bonds in these complexes are essentially less reactive than those in the free silanes. Thermolysis reactions proceed under splitting of the Si-C bond. They confirm the different reactivities of the heterocyclic substituted silanes and suggest a new mechanistic variation of the electrophilic substitution-type reactions.  相似文献   

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Ohne ZusammenfassungVgl. diese Z. 137, 129 (1952/53); 138, 118 (1953)  相似文献   

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