Preparation and crystal structure of the La2Ni12P5 and isotypic ternary lanthanoid—Nickel phosphides

The new ternary phosphide La₂Ni₁₂P₅ has been prepared by direct arc melting of the components as pure metals and red phosphorus. The crystal structure has been determined using X-ray single crystal diffraction data. The compound exhibits a new type of crystal structure, P2₁/m with lattice parameters a = 10.911(3), b = 3.696(2), c = 13.174(4) Å, β = 108.02(2)°, V = 505,2(6) ų, Z = 2. Atomic parameters least squares refinement of 116 independent variables (anisotropic approximation for thermal vibrations) employed 1 284 independent I_o(hkl); R_F = 0.0278 and R_W = 0.0287. The crystal structure is characterized by trigonal prismatic arrangement of phosphorus atoms stacking variant of infinite (with phosphorus centered) columns built by metal trigonal prisms ‖ [010]. Two or three such columns are connected through common edges (lanthanum atoms). The compounds RE₂Ni₁₂P₅ (where RE = Ce, Pr, Nd and Eu) display the same with La₂Ni₁₂P₅ crystal structure. Lattice parameters of these compounds have been refined using powder diffraction data.     

Electron spin echo as a tool for investigation of surface structure of finely dispersed fractal solids

The ESE method was successfully used for investigating the texture of the adsorbents and catalysts. Equations were obtained for the kinetics of ESE signal decay due to dipole-dipole interaction between motionless paramagnetic centers distributed uniformly on the fractal surface of solid.

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Zwei neue pentacyclische dimere des cycloheptatriens

Titanium - catalyzed dimerization of cycloheptatriene affords pentacyclo[7.5.0.0^2,8.0^5,14.0^7,11]tetradeca-3,12-diene, $\text{3}$, and pentacyclo[8.4.0.0^3,7.0^4,14.0^6,11]tetradeca-8,12-diene, $\text{4}$. By heating, $\text{3}$ is converted quantitatively into $\text{4}$.     

Ion-pair extraction of pentacaine from biological materials

Simple and rapid extraction method for quantitative and selective isolation of the new local anesthetic pentacaine from biological materials is proposed. The technique of ion-pair formation was found to be more effective than usual access using the extraction of the nonionized species. The extraction yield of the unchanged molecule³H-pentacaine after double extraction and single scrubbing was found to be more than 90%. The radiochemical purity was over 90%. The method appears suitable for pharmacokinetic studies in the animal body.     

Synthesis of nucleosides of substituted 3-hydroxypyrazoles

N-Glucoside analogs of the antibiotic pyrazofurine were obtained by fusion of 3-hydroxy-4-ethoxycarbonylpyrazole with tetra-O-acetyl-ß-D-ribofuranose in the presence of iodine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1512–1514, November, 1981.     

New Tricyclic Amides. Synthesis,Structure, and Oxidation with Peroxyphthalic Acid

4-Azatricyclo[5.2.1.0^2,6]dec-8-ene was synthesized and brought into reactions with benzoyl, o-chlorobenzoyl, p-bromobenzoyl, p-, m-, and o-nitrobenzoyl, and bicyclo[2.2.1]hept-2-ene-endo-5,endo-6-dicarboximidoacetyl chlorides in chloroform in the presence of pyridine. The tricyclic amides thus obtained were epoxidated with peroxyphthalic acid prepared in situ by reaction of phthalic anhydride with a 35% aqueous solution of hydrogen peroxide. The structure of newly synthesized compounds was confirmed by IR and ¹H and ¹³C NMR spectroscopy and mass spectrometry. Their NMR spectra were compared with those of previously synthesized N-arylsulfonyl-4-azatricyclo[5.2.1.0^2,6]dec-8-enes on the basis of conformational composition of the corresponding p-nitrophenyl-substituted derivatives, which was determined by PM3 semi-empirical quantum-chemical calculations.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 837–845.Original Russian Text Copyright © 2005 by L. Kas’yan, Okovityi, Tarabara, A. Kas’yan, Bondarenko.     

Spectroscopic study of low temperature interactions in metal-organic co-condensates

The results on spectroscopic study of low temperature interactions of metal atoms, small clusters and nanoparticles with different organic and inorganic substances in the temperature range 12-300 K are presented. Complexation and reactions of atoms and clusters of magnesium, samarium and silver with carbon dioxide, ethylene and some mesogenic cyanophenyls were studied by the technique of matrix isolation and low temperature co-condensation of metal and ligand vapors, low temperature UV-Vis, IR- and ESR-spectroscopy in combination with quantum chemistry calculations. It was shown that cryochemical reactions of metal particles of different sizes reflected the system's redundant energy.     

Vibrational spectra and conformations of 2- and 3-methylbicyclo[4.4.0]decanes

The conformations and heats of formation of all trans(T)- and cis(C)-2- and 3-methyl-substituted T- and Cbicyclo[4.4.0]decanes (BD) were calculated by the MM2 method of molecular mechanics. It was shown that the conformationally mobile T-2-Me-CBD and T-3-Me-CBD can exist in normal conditions as an inseparable mixture of conformers with a different equatorial or axial orientation of the Me groups. The Raman scattering (RS) spectra of TBD and CBD were investigated. RS bands whose frequencies were sensitive to the type of ring linkage and orientation (but not the position) of the Me substituents were detected in the 700–300 cm^–1 region.A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 117912 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2089–2097, September, 1992.     

7-Aryl-6,7-dihydro-8h-indeno[1′,2′∶2,3]pyrano-[5,6-c]benzo[c]pyran-6,8-diones and their thio analogs

The ability of 3-[-(1,3-dioxo-2-indanyl)benzyl]-4-hydroxy-substituted 2H-benzo [b]pyran-2-ones and benzo[b]thiopyran-2-ones to undergo dehydration under the influence of dehydrating agents to give 7-aryl-6,7-dihydro-8H-indeno[1,2-2,3]pyrano[5,6-c]benzo[c]pyran-6,8-diones and their thio analogs was demonstrated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1475–1476, November, 1985.     

Effect of temperature on the basicity of certain aliphatic-aromatic amino alcohols

Conclusions Ionization constants were obtained of 14 amino alcohols and one tertiary amine in 50% ethanol in the range of 10–25° and thermodynamic characteristics of the ionization process of the investigated ammonium ions were calculated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 669–671, March, 1976.The authors express their gratitude to S. V. Bogatkov for participation in discussion of the obtained results.