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[en] The results of studies dealing with mechanisms of hydro-, carbo- and cycloalumination of alkenes and alkynes catalyzed by zirconium complexes are generalized and systematized for the first time. Data about the structures of intermediates responsible for the formation of the target compounds are presented and the available data on the effect of the structure of organoaluminium compounds and the electronic and steric factors determining the catalytic activity of metal complexes in these reactions are considered in detail. Much attention is paid to studies of the influence of reaction conditions on the chemo-, regio- and stereoselectivity of the Zr-containing complex catalysts. The bibliography includes 217 references.

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[en] A series of 23 bis(phenoxy imine) zirconium complexes (Fi complexes) containing halogen or alkynyl substituents in their ligand frameworks was synthesized and characterized. After activation with methoxyethylamine (Mao), these catalysts polymerize ethylene with good activities. Halogen or alkynyl functions may be used as anchoring po ins in subsequent Sonogashirea type coupling reactions.

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[en] A protometric study on the speciation of zirconium(IV) was performed in an aqueous solution at 25 C in KNO₃ and four ionic strengths (0.2, 0.5, 1, and 2 mol x dm^-3). This study indicates the formation of the soluble species Zr(OH)₃⁺, Zr₂(OH)₇⁺, and Zr(OH)₄ in the pH range 1.5-3.5. The use of an appropriate titration technique allows the precipitation of the zirconium hydroxide to be limited. The overall stability constants β_mlh of these three hydroxo complexes were computed and refined, by the program PROTAF, for each ionic strength. The solubility product Ks of Zr(OH)₄ was calculated by taking these β_mlh constants into account. The thermodynamic values were determined by extrapolation at zero ionic strength (Specific ion Interaction Theory method): log β _10-3=-0.52 (0.01); logβ _20-7=-2.22(0.07); logβ _10-4=-4.52 (0.07); logKs =-55.26(0.08). (orig.)

[en] An efficient method of addition of trimethylsilyl cyanide to aldehydes by employing a zirconium complex as the catalyst has been described. A variety of aromatic, aliphatic, cyclic and heterocyclic aldehydes has been converted into corresponding trimethylsilyl ethers in excellent yield within short reaction time

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[en] The sensitive spectrophotometric method for the determination of microgram amounts of zirconium using the reaction with phenylfluorone (PF) in the presence of lauryldimethylbenzylammonium bromide (ST) was elaborated. The complex has absorption maximum at 532 nm in 0.1 mol l^-1 HCl medium. Molar absorptivity is 1.38 x 10⁵ l mol^-1 cm^-1. The range of determination of zirconium is 0.02-0.14 μg ml^-1. Only tin(II), molybdenum, antimony(III), germanium, vanadium(V), mercury(II) and chromium(VI) disturb the determination. The elaborated method was used to determine zirconium in the brass. (author). 13 refs, 2 figs, 2 tabs

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