Tetraphenylbismuth 2,4-Dimethylbenzenesulfonate: Synthesis and Structure

Tetraphenylbismuth 2,4-dimethylbenzenesulfonate was synthesized by reacting pentaphenylbismuth or bromine with diphenylbismuth 2,4-dimethylbenzenesulfonate and its structure was established using X-ray diffraction analysis. The Bi atom has a distorted trigonal bipyramidal coordination. The Bi–C bond lengths are equal to 2.199(4)–2.227(4) Å the Bi–O distance and axial CBiO angle are equal to 2.665(3) Å and 174.2(1)°, respectively.     

Kinetics of Gold Electrodeposition from Cyanide Electrolytes at a Monitored Surface Coverage by Thallium Atoms

A procedure for measuring kinetic parameters of gold electrodeposition in the presence of catalytically active thallium(I) ions while monitoring the coverage of the gold surface by thallium adatoms, , is described. The procedure accounts for the duration of contact between a freshly renewed surface of gold and a thallium-containing solution and assumes that the incorporation rate of thallium adatoms is proportional to and the current density of gold electrodeposition. At = const, kinetic dependences correspond to the Tafel equation. Values of and i ₀ increase with . At = 0.3, 0.6 and i ₀ 3 × 10^–4 A cm^–2, which conforms to values calculated from anodic curves obtained in similar conditions.     

Composition and properties of polysaccharides from rice husk

The composition and content of polysaccharides obtained from different samples of rice husk by successive treatment with water, ammonium oxalate (or oxalic acid), and alkali were studied. The chemical composition of the rice husk residues after the extraction was examined, and the possibility of their use for preparing amorphous silica or cellulose-containing products, depending on the hydrolysis conditions, was assessed.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1901–1904.Original Russian Text Copyright © 2004 by Zemnukhova, Tomshich, Mamontova, Komandrova, Fedorishcheva, Sergienko.     

Ion Mobility,Phase Transitions,and Ion Conductivity in Alkali Metal Tetrafluoroantimonates(III) MSbF4 (M = Na,K, Rb,Cs)

The internal mobility of fluoride ions and electrophysical characteristics of alkali metal tetrafluoroantimonates(III) (M = Na, K, Rb, and Cs) are studied by ¹⁹F NMR and impedance spectroscopies. The types of ion motions in the anionic sublattice of these compounds are determined in the 180-510 K temperature range. The superionic conductivity of the MSbF₄ compounds is established above 480 K ( 2.9 × 10^-2 to 1.3 × 10^-4 S/cm).     

Synthesis of β-Aminophosphonates and Study of Their Acid-Base Properties and Phase Distribution in Water-Organic Solvent Systems

New and previously known β-aminoethylphosphonates were synthesized by addition of primary and secondary amines to vinylphosphonates, and their IR and NMR spectra were examined. Diethyl 2-diethylaminoethylphosphonate and diethyl 2-morpholinoethylphosphonate were found to be stronger bases than the corresponding aminomethylphosphonates, but all these are weaker bases than their precursors, nonphosphorylated amines. Distribution constants of β-aminophosphonates between water and some organic solvents were determined and compared with those of their α-amino homologs.     

Polymeric Formulations Based on Iron and Cobalt Molybdophosphates and Polyacrylates

The possibility of using synthesized iron(III) and cobalt(II) molybdophosphates as dyes in dyeing of copolymers and polymeric formulations based on methacrylic acid and methyl methacrylate and also as pigments deposited onto natural and inorganic supports for heterogeneous dyeing of polymeric materials was studied.     

Rapid Determination of Explosives and Narcotics Using a Multicapillary-Column Gas Chromatograph and an Ion-Mobility Spectrometer

A gas chromatograph for the rapid determination of explosives (2,4-dinitrotoluene, 2,4,6-trinitrotoluene, and pentaerythritol tetranitrate) and narcotics (heroin, cocaine hydrochloride, and crack) is described, and its analytical characteristics are presented. The instrument was equipped with a multicapillary column and an ion-mobility spectrometer as a detector.     

Acid-catalyzed oligomerization of aromatic ethers (Rolivsans) with terminal styrene and methacrylate groups

Cationic mechanism of transformation of unsaturated aromatic monomers contained in Rolivsans into thermosetting aromatic oligoethers with increased molecular weight was analyzed. The composition and chemical structure of Rolivsans as influenced by catalytic systems with various donor-acceptor properties were studied.     

Crystal structure of 1-[N-2-aminoethyl)-aminopropyl]silatrane

The crystal structure of 1-[N-(2-aminoethyl)aminopropyl]silatrane has been determined by x-ray diffraction at room temperature. The Si←N bond distance (2.165(2) Å) is in the range observed for other 1-X-propylsilatranes (X = CN, OH, SH, Cl and SCN). The structure is partially disordered: the silatrane moiety displays a disorder that is typical for silatranes and the aminoethyl group terminating the planar chain linked to silicon is rotationally disordered.     

Xanthones from the roots ofSwertia iberica

From the roots ofSwertia iberica, together with the previously known swertiaperennin decussatin, gentiakochianin, and norswertianin, we have isolated two new xanthones — isogentiakochianin and swertiaiberin. On the basis of UV, IR, PMR, and mass spectroscopy, the structure of 1,3,8-trihydroxy-7-methoxyxanthone is proposed for isogentiakochianin, and that of 1,2,3-trihydroxy-7,8-dimethoxyanthone for swertiaiberin.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 190–195, March–April, 1980.