Regioselective Alkoxyiodination of Allyl Ethers in Unsaturated C3-Alcohols

Russian Journal of Organic Chemistry - Alkoxyiodination of alkyl allyl ethers with elemental iodine in allyl and propargyl alcohols in the presence of clinoptilolite [(NaK)4CaAl6Si30O72] gave the...     

3-Substituted Thietanes as Effective Inhibitors of Cumene Oxidation

3-Substituted thietanes were prepared by reaction of 1,2-epithio-3-chloropropane with various nucleophiles in aqueous solutions and were characterized. The inhibiting power of these compounds in cumene oxidation was studied.     

Correction to: Influence of Magnetite Nanoparticles on the Dielectric Properties of Metal Oxide/Polymer Nanocomposites Based on Polypropylene

Russian Physics Journal - The name of the first author should read A. М. Maharramov.     

Determination of the crystal structure of diopside (Ca0.8Fe0.2)(Mg0.8Fe0.2)Si2O6 from the Gazakh Trough (Azerbaijan)

The crystal structure of a clinopyroxene is determined by X-ray diffraction. The unit cell parameters are as follows: a = 9.732(7) ?, b = 8.896(6) ?, c = 5.280(4) ?, and ?? = 106.160(11)°; V = 439.1(5) ?³; space group C2/c; and Z = 4. The structure is determined by the direct method and refined in the anisotropic approximation by the full-matrix least-squares method (R[F ² > 2??(F ²)] = 0.027, wR(F ²) = 0.072). According to the results of the X-ray structure analysis, the crystal chemical formula of the compound is (Ca_0.8Fe_0.2)(Mg_0.8Fe_0.2)Si₂O₆. In the structure, columns of (Mg, Fe)-octahedra are connected on two sides with Si₂O₆ chains. The resulting structural units have the [(Mg,Fe)₂(Si₂O₆)₂]^4? composition. These units form a heterogeneous framework, which is typical of all pyroxene structures. The [(Mg,Fe)₂(Si₂O₆)₂]^2? composition of the framework corresponds to the ratio [(Mg,Fe) + Si]: O = 3: 6 (1: 2). The (Ca, Fe) atoms are located in the holes of the framework.     

Ammonium salt of the cross-linked maleic acid–allylpropionate–styrene terpolymer as effective sorbent for removal of Cu2+ ions from water solutions (sorption of the copper ions)

The capability of the ammonium salt of the cross-linked maleic acid–allylpropionate–styrene terpolymer for the adsorption of Cu²⁺ from aqueous solutions was examined. Effect of the various experimental parameters on removal degree of the copper ions was investigated. Equilibrium data were fitted to the Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin isotherm models. Kinetics studies suggested that the adsorption allowed pseudo-second-order reaction. The negative values of ΔG° and the positive value of ΔH° indicate that the sorption process is spontaneous and endothermic in nature. The positive value of ΔS° shows the increasing randomness during adsorption process. Considering the FTIR and UV–vis spectra of the sorbent after sorption, it is concluded that Cu²⁺ enters a complex with carboxylate and ester groups of the sorbent.     

Hydrothermal synthesis and the crystal structure of borate cancrinite (Na,Ca)2[Na6(AlSiO4)6](BO3) · 2H2O

Transparent prismatic single crystals of borate cancrinite (Na,Ca)₂[Na₆(AlSiO₄)₆](BO₃) · 2H₂O are prepared through hydrothermal crystallization. The parameters of the hexagonal unit cell and intensities of 10806 reflections are measured on an Enraf—Nonius CAD4 automated diffractometer. The compound crystallizes in the hexagonal crystal system with the unit cell parameters a = 12.745(4) Å, c = 5.180(2) Å, V = 728.6(4) ų, and space group P6₃. The structure is determined by direct methods and refined using the full-matrix least-squares procedure in the anisotropic approximation for the non-hydrogen atoms. The refinement of the structure is performed to the final discrepancy factor R ₁ = 0.027 for 2889 unique reflections with I > 2 σ (I). In the structure of the borate cancrinite, the AlO₄ and SiO₄ tetrahedra form a zeolite-like framework in which twelve-membered hexagonal channels are occupied by sodium atoms and BO₃ groups, whereas six-membered channels are filled with sodium and calcium atoms and water molecules. The mean interatomic distances are found to be as follows: (Si-O)_mean = 1.614 Å and (Al-O)_mean = 1.741 Å in the AlO₄ and SiO₄ tetrahedra, (Na-O)_mean = 2.542 Å in the seven-vertex sodium polyhedra, and [(Na,Ca)-O]_mean = 2.589 Å in the ditrigonal bipyramids.