Formation of nitrophenols in the gas-phase nitration of benzene over solid catalysts

Russian Journal of Organic Chemistry -     

Vapour pressures and enthalpies of vapourization of a series of the γ-lactones

Vapour pressures and the molar enthalpies of vapourization of the γ-lactones (γ-valerolactone, γ-hexanolactone, γ-heptanolactone, γ-nonanolactone, and γ-decanolactone) have been determined by the transpiration method. These results together with a large number of experimental data from the literature have been checked for internal consistency. This collection has been used for development of group-additivity procedure for prediction of vapourization enthalpies of lactones.     

Yuriĭ Andreevich Osip’yan (February 15, 1931–September 10, 2008)

Crystallography Reports -     

NMR and cation-cation interactions involvings 2 lone pairs

The results of NMR spectroscopy on^203,205Tl,²⁰⁷Pb,¹²⁵Te, and other nuclei are used to characterize an anomalous effect of the s² lone pair on interatomic interactions in the fluorides, oxides, and chalcogenides of some elements of Groups 13–18 of the periodic table. Data for crystals of TISe structural type and related compounds, for various structural modifications of TIF, PbO, and TeO₂ crystals, and also for liquids and liquid solutions [(TIOC₂H₅)₄, (XeF₆)₄, etc.], of vanadium tellurite and lead silicate glasses are considered. It is shown that the electronnuclear interactions and the structural peculiarities of compounds with underoxidated cations are due to the effect of the excited states of ions with the electronic configuration s². Translated fromZhumal Strukturnoi Khimii, Vol. 38, No. 1, pp. 173–195, January–February, 1997.     

Synthesis of hydrocarbons from Co and H2 in the presence of supported Co catalysts modified by palladium

A study has been made of the effect of Pd on the activity and selectivity of Co catalysts prepared by impregnating various supports (SiO₂, SiO₂-Al₂O₃, Al₂O₃) with cobalt carbonyl or nitrate in the synthesis of hydrocarbons from CO and H₂. It is shown that the addition of Pd leads to an increase in the yield of liquid hydrocarbons and to a change in their composition. It has been established by IR spectroscopy that the introduction of Pd into the composition of carbonyl catalysts affects the formation of their surface.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 521–524, March, 1990.     

Dinitramide and its salts

N,N-Dinitro derivatives of alkylurethanes, benzamide, andp-toluenesulfamide were synthesized for the first time. Their reactions with ammonia afforded the ammonium salt of dinitramide in 44–85% yields.For part 9, seeIzv. Akad. Nauk. Ser. Khim., 1996, 451 [Russ-Chem. Bull., 199645, 433 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 908–912, April, 1996.     

Phytochemical Characterization,Antioxidant Activity,and Cytotoxicity of Methanolic Leaf Extract of Chlorophytum Comosum (Green Type) (Thunb.) Jacq

Chlorophytum genus has been extensively studied due to its diverse biological activities. We evaluated the methanolic extract of leaves of Chlorophytum comosum (Green type) (Thunb.) Jacques, the species that is less studied compared to C. borivilianum. The aim was to identify phytoconstituents of the methanolic extract of leaves of C. comosum and biological properties of its different fractions. Water fraction was analyzed with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Nineteen compounds belonging to different chemical classes were identified in the methanolic extract of leaves of C. comosum (Green type) (Thunb.) Jacques. In addition to several fatty acids, isoprenoid and steroid compounds were found among the most abundant constituents. One of the identified compounds, 4′-methylphenyl-1C-sulfonyl-β-d-galactoside, was not detected earlier in Chlorophytum extracts. The water fraction was toxic to HeLa cells but not to Vero cells. Our data demonstrate that methanolic extract of leaves of C. comosum can be a valuable source of bioactive constituents. The water fraction of the extract exhibited promising antitumor potential based on a high ratio of HeLa vs. Vero cytotoxicity.     

Anodic oxide-film of the Co—Sn—O composition

Properties and electrocatalytic activity of thin-film (∼2 μm) oxide coatings on aTi support are considered by the example of the anodic chlorine evolution reaction. The coatings are obtained by thermally decomposing Co and Sn chloride solutions of different compositions on a Ti plate. The Co and Sn oxides are present in all studied compositions as individual phases and form no compounds or solid solutions. The oxide coating containing 70 at. % Co and 30 at. % Sn reveals a maximum electrocatalytic activity. The existence of the optimum composition is attributed to a favorable effect tin dioxide has on the formation of a transition layer between the Ti support and oxide coating. Tin dioxide hampers the Ti diffusion in the main coating and its subsequent oxidation, thus diminishing the negative impact titanium oxides have on the coating     

New catalytic systems for oxidative carbonylation of acetylene to maleic anhydride

A classification of polyfunctional catalytic systems based on discrimination of the main component (the catalyst participating in all stages of the formation of the product of catalytic reaction) and elucidating the functions of additional components of a catalytic system is suggested. The role of additional components in a number of new palladium-based catalytic systems used in the synthesis of maleic anhydride by oxidative carbonylation of acetylene was studied. It was established that the functions of Co and Fe phthalocyanine complexes (PcCo and Pc^*Fe, respectively) in the mechanism of the process are different. Translated fromIzvestia Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1899–1905, October, 1999.