Preparation of gem-dinitroparaffins

Summary A series of gem-dinitroparaffins, from 1,1-dimtropropane to 1,1-dinitrodecane, were prepared by Chancel's reaction; their constants were measured, and the refraction of the dinitromethyl group was determined.     

Optically active triosmium clusters containing the cysteine ligand

The reactions of cysteine ethyl ester with a series of triosmium clusters have been studied. Enantiomeric (-H)Os₃{-SCH₂CH(CO₂Et)NH₂}(CO)₁₀ and diastereomeric (-H)Os₃{-²-SCH₂CH(CO₂Et)NH₂}(CO)₉ forms of the optically active cluster complexes have been obtained. Diastereomeric clusters have been separated by TLC on Silufol plates. The treatment of the enantiomeric complex (-H)Os₃{-SCH₂CH(CO₂Et)NH₂}(CO)₁₀ with the trimethylamine oxide yields the diastereomeric pair (-H)Os₃{-²-SCH₂CH(CO₂Et)NH₂}(CO)₉. The structures of the complexes obtained have been established on the basis of IR,¹H NMR and mass spectrometry as well as X-ray analysis data.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1981–1984, November, 1993.     

Optical and Chromaticity Characteristics of Cobalt and Palladium 4-(2-Pyridylazo)resorcinates

Optical and chromaticity characteristics (diffuse reflectances, chromaticity coordinates, lightness, color saturation, yellowness, color tint, and whiteness) of cobalt and palladium complexes of 4-(2-pyridylazo)resorcinol were determined at pH 7.2–7.9 and in 1 M H₂SO₄. The conditions of the separate determination of cobalt and palladium in the presence of each other by changing the order of the addition of reagent and using bifunctional chromaticity measurements and two-wavelength spectrophotometry are specified. The advantages of the chromaticity measurements are demonstrated. The proposed procedures were used for the analysis of model mixtures, binary cobalt–palladium alloys, and cobalt and palladium catalysts.     

The thermodynamic properties of uranyl metaborate

The standard enthalpy of formation of crystalline UO₂(BO₂)₂ at 298.15 K was determined by reaction calorimetry (?2542.5 ± 3.5 kJ/mol). The heat capacity of this compound was measured over the temperature range 6–302 K by adiabatic vacuum calorimetry. The thermodynamic functions were calculated, including the standard entropy (502.8 ± 2.1 J/(mol K)) and Gibbs function of formation (?2392.5 ± 4.0 kJ/mol) at 298.15 K. The standard thermodynamic functions of reactions with the participation of uranyl metaborate were determined and analyzed.     

Synthesis,structures, IR spectra,and thermal characteristics of compounds of general formula Ba(M<Stack><Subscript>2/3</Subscript><Superscript>III</Superscript></Stack>U<Subscript>1/3</Subscript>)O<Subscript>3</Subscript> (M<Superscript>III</Superscript> = Sc,Y, In,Nd-Lu)

Compounds with the composition Ba(M _2/3 ^III U_1/3)O₃ (M^III = Sc, Y, In, Nd-Lu) were synthesized by high-temperature solid-state reactions. The structures of the compounds were studied by X-ray diffraction analysis, including the high-temperature method, and IR spectroscopy.     

Direct determination of traces of beryllium with eriochrome cyanine R by diffuse reflection spectroscopy using chromaticity functions

Chromaton-N-super and Silasorb C18 (SMT C18) were compared as solid supports for the direct determination of the immobilized beryllium complexes with eriochrome cyanine R by diffuse reflection spectroscopy. The advantage of Silasorb C18 was shown. A detection limit of 0.0002 microg mL(-1) could be reached in a 100-mL sample. The method was used for the analysis of real water samples.     

Complexes of Group III Metals based on o-Iminoquinone Ligands

Russian Journal of Coordination Chemistry - The currently available published data on the synthesis, structure, and chemical properties of Group III metal complexes based on bi-, tri-, and...     

Synthesis and properties of quinazoline derivatives containing cymantrenyl group

The synthesis of new quinazoline derivatives with 2,3- and 4-positioned cymantrenyl fragment is described. Alkylation of 2-substituted quinazolin-4-ones with cymantrenylalkyl bromides on using K₂CO₃, potassium tert-butoxide, and sodium hydride as bases has been studied. It is established for the first time that condensation of 2-methylquinazolin-4-ones with aldehydes can cause elimination of the substituent at the nitrogen atom in position 3. The new cymantrene derivatives possess fluorescence properties.     

NMR Study of the Interaction of Tin(II) and Antimony(III) Fluorides with Phosphorus Chlorides

Reactions of SnF₂ and SbF₃ with POCl₃ and PCl₅ in acetonitrile were studied by ¹⁹F, ³¹P, and ¹¹⁹Sn NMR. Tetrahedral compounds POF₂Cl and POF₃ form in the reaction with POCl₃. Interaction of SnF₂ and SbF₃ with PCl₅ yields higher (in terms of fluorine) octahedral complexes [PF₅ · MeCN] and [PF₆]^–. In all cases, fluorine-free phosphorus compounds are found in the acetonitrile solution.     

The Thermodynamic Properties of Barium Uranoborate and Its Dihydrate

The standard enthalpies of formation of crystalline Ba(BUO₅)₂ and Ba(BUO₅)₂ · 2H2O at 298.15 K were determined by reaction calorimetry. The temperature dependences of the heat capacities of these compounds were studied over the temperature range 7–340 K by adiabatic vacuum calorimetry, and their thermodynamic functions were determined. The standard entropies and Gibbs functions of formation of these compounds at 298.15 K were calculated.