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1.
The inductive constant σ* of the succinimide group was determined using the previously obtained equation correlating the rate constant k l ofliquid-phase homolysis of the O-NO2 bond in nitro esters with the σ* constants of electronegative substituents. The kinetics of thermolysis of N-nitroxymethyl- and N-(2-nitroxyethyl)succinimide in the melt and solutions was studied manometrically. Adequate data for k l were obtained. The σ* constant of the succinimide group was determined to be 4.5. The σ* constants for the phthalimide group and some other imide substituents were determined by a similar procedure.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 6, 2005, pp. 954–957.Original Russian Text Copyright © 2005 by Goncharov, Dubikhin, Nazin, Fedorov, Shastin.  相似文献   

2.
N,N′-Bis(trimethylsilylmethyl)-λ6-thiocarbamide S,S-dioxide was synthesized by oxidation of N,N′-bis(trimethylsilylmethyl)thiocarbamide with hydrogen peroxide. The synthesized dioxide is a less active reducing agent than previously studied S,S-dioxides of organosilicon thiocarbamides in which the silicon atom is separated from the thiocarbamide fragment by a -CH2CH2CH2- bridge.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 6, 2005, pp. 912–914.Original Russian Text Copyright © 2005 by Vlasova, Grigor’eva, Voronkov.  相似文献   

3.
Amination and amidation of bromoindole, 6-bromo-1,2,3,4-tetrahydrocarbazol-1-one, and 8-bromo-2,4,5,6-tetrahydro-1H-pyrazino[3,2,1-jk]carbazole derivatives was effected in the presence of palladium complexes. The use of the catalytic system Pd2dba3⋅CHCl3-2-[di(tert-butyl)phosphino]biphenyl in the amination and of Pd2dba3⋅CHCl3-Xantphos [or 3,5-(CF3)2Xantphos] in the amidation ensured moderate to high yields of the corresponding products.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 881–894.Original Russian Text Copyright © 2005 by Sergeev, Artamkina, Velezheva, Fedorova, Beletskaya.  相似文献   

4.
Indium dodecatungstosilicate of the composition [In(OH)⋅5H2O]2 [SiW12O40]⋅H2O is synthesized and studied by means of IR spectroscopy, thermogravimetry, and X-ray phase analysis. The crystals of this compound are triclinic, space group P1, a 13.079(3), b 13.795(3), c 13.967(3) Å, α 90.08(3)°, β 103.76(3)°, ψ107.76(3)°, Z 2, and πcalc 4.900 g cm−3.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 1, 2005, pp. 21–23.Original Russian Text Copyright © 2005 by Kaziev, Dutov, Quinones, Ita, Sychkin.  相似文献   

5.
Molecules of a series of heteroaromatic azides in the ground (S 0) and the lowest excited singlet (S 1) states were calculated by the PM3 semiempirical method. It was shown that in the S 0 state, the azide group in all the azides has quasi-linear geometry and a significant positive charge on the two terminal nitrogen atoms. The azide photoactivity is determined by the population of the σ NN * orbital in the excited state, which is unoccupied in the ground state. The population of this orbital was found to depend on the size and charge of the aromatic π system. For the initial members of this azide series, the σ NN * orbital is populated in both neutral and protonated forms. This is consistent with the experimental data and means that these azides are photoactive. With an increase in the size of the aromatic system, the energetic gap between the σ NN * orbital and LUMO increases. As a result, the σ NN * orbital is not populated in the S 1 state when a particular threshold size of the π system is achieved, and the azide becomes photo-inactive.__________Translated from Khimiya Vysokikh Energii, Vol. 39, No. 4, 2005, pp. 259–266.Original Russian Text Copyright © 2005 by Budyka, Oshkin.  相似文献   

6.
In terms of the molecular fragment principle, a quaternary complex is assembled under hydrothermal conditions and characterized as [Tb(BAA)2(Phen)(NO3)]2 (BAA is benzoyl acetic acid, Phen is 1,10- phenanthroline) by elementary analysis and IR, UV, fluorescence excitation, and emission spectra. The X-ray single-crystal diffraction data indicate that the title complex crystallizes in triclinic system, space group , with unit cell parameters a = 8.953(6), b = 13.332(9), c = 13.431(9) Å, α = 60.669(7)°, β = 89.649(8)°, γ = 72.068(9)°, V = 1309.3(15) Å3, ρ(calcd) = ∼ 1.703 g/cm3, Z = 1 (per dimeric unit), F(000) = 664, GOOF = 1.071, R 1 = 0.0627. The terbium complex forms a dimer with a coordination number of nine in which each pair of adjacent terbium ions is bridged by four BAA groups via two types of coordination modes. The dimer exhibits strong green luminescence of Tb3+.__________From Koordinatsionnaya Khimiya, Vol. 31, No. 6, 2005, pp. 472–478.Original English Text Copyright © 2005 by Bai, Yan, Chen.  相似文献   

7.
The reaction of 2-hydroxy-3-(4,5-diphenyl-1,3-oxazol-2-yl)-1-naphthaldehyde with 1,2,3,3-tetramethyl-3H-indolium perchlorate afforded photochromic spiro[indoline-2,3′-naphthopyran] containing a 4,5-diphenyloxazole group in position 5′ of the naphthopyran fragment. The merocyanine form of the spiropyran gave complexes with bivalent heavy cations.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 693–697, March, 2005.  相似文献   

8.
By reaction of Z-3-(2-naphthyl)-3-chloro-2-propenal with semicarbazide hydrochloride and thiosemicarbazide the corresponding semicarbazone and thiosemicarbazone were obtained that underwent a heterocyclization into a pyrazole system with elimination of amide moieties and with migration of the naphthyl fragment into the position 4 of the pyrazole ring. The alkylation of 4-(2-naphthyl)pyrazole synthesized with 2-nitropentachloro-1,3-butadiene afforded 1,1-bis[4-(2-naphthyl)-pyrazol-1-yl]-2-nitrotrichloro-1,3-butadiene.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 753–755.Original Russian Text Copyright © 2005 by Vashkevich, Potkin, Kozlov.  相似文献   

9.
Drim-9(11)-en-8α-ol and drim-9(11)-en-8β-ol were synthesized in six steps from drimenol. Drimenol was oxidized by P2O5 and DMSO to drimenal, which isomerized with p-TsOH into isodrimenal. Isodrimenal was reduced by NaBH4 into isodrimenol, epoxidation of which by m-CPBA gave a mixture (3.4:1) of α- and β-epoxyisodrimenols. These reacted with tosyl chloride in Py to give a mixture of α- and β-epoxyisodrimenol tosylates. Treatment of the tosylate mixture with KI and then Ph3P produced a mixture of drim-9(11)-en-8α- and -8β-ols that was separated chromatographically. The overall yield was ∼26%.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 152–155, March–April, 2005.  相似文献   

10.
The protolytic properties of N,N-dimethyl-N′-(2-hydroxybenzyl) ethylenediamine (HL) and its complexation with copper(II) in the presence of cationic (cetyltrimethylammonium bromide) and nonionic (Triton X-100) surfactants were studied by pH-metry, spectrophotometry, and mathematical simulation of the equilibria. Cetyltrimethylammonium bromide affects the H2L2 ⇄ 2HL equilibrium. Along with the protonated monomeric and dimeric species, triprotonated tetrameric species were revealed in surfactant solutions, as in aqueous solutions of isopropyl alcohol. The surfactants affect the complexation of HL with Cu(II). The 1 : 2 complex with the phenolate form in solutions of cetyltrimethylammonium bromide is formed in a more acidic medium (pH ∼5.5) compared to an aqueous solution of isopropyl alcohol (pH ∼11). The apparent stability constants of the complexes increase in the presence of surfactants, especially of cetyltrimethylammonium bromide.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 379–382.Original Russian Text Copyright © 2005 by Sal’nikov, Boos, Ryzhkina, Ganieva.  相似文献   

11.
Free P(SMe)3 molecule was studied by gas electron diffraction (GED) and by B3PW91/6-311+G* (DFT) and MP2/6-31+G* calculations. Each conformer is characterized by three dihedral angles τ(CSPlp), where lp denotes the direction of the lone electron lone pair on the P atom. DFT calculations indicate that the most stable conformer is an anti,gauche+,gauche- (ag+g-) conformer of C s symmetry; the next are the ag+g+ (ΔE = 2.5 kJ mol−1), g+g+g+ (ΔE = 5.2 kJ mol−1), and aa+g+ (Δ E = 12.5 kJ mol−1) conformers. The MP2 calculations give the similar order, with the relative energies of 0.3, 4.3, and 10.6 kJ mol−1, respectively. The experimental GED data agree well with the presence of only two conformers: χ(ag+g+) = 80(20)% and χ(ag+g-) = 20(10)%.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 742–750.Original Russian Text Copyright © 2005 by Belyakov, Khramov, Baskakova, Naumov.  相似文献   

12.
The geometric structures of the ground state and metastable isomers of the nitroso complexes trans-[RuCl4(NO)L]q (L = H2O, NH3, pyrazine (Pz), q = −1; Cl, OH, CN, NO 2 , q = −2) and cis[RuCl4(NO)L]q (L = Pz, q = −1) were optimized in terms of the density functional theory. The variation of the trans-ligand L influences the relative energy of the metastable isomer with a side NO coordination. The presence of π-acceptor substituents in the trans-ligand L decreases the energy.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 8, 2005, pp. 606–611.Original Russian Text Copyright © 2005 by Lyubimova, Sizova.  相似文献   

13.
Single crystals of the heterovalent CuI,CuII π,σ-complex Cu7Br6.48Cl1.52 ⋅ 2C3N3(OC3H5)3 are synthesized by the ac electrochemical method from an ethanol solution containing 2,4,6-triallyloxy-1,3,5-triazine, CuCl2 ⋅ 2H2O, and CuBr2. The unit cell parameters of the crystals are: space group , a = 8.271(3) Å, b = 11.391(3) Å, c = 11.821(3) Å, α = 67.43(1)°, β = 84.41(2)°, γ = 85.14(2)°, V = 1022(1) Å3, and R(F) = 0.0714. The copper and halogen atoms form unique moieties Cu6X6 linked by bridging fragments [Cu2+ (C3N3(OC3H5)3)2]X2 into infinite chains. Each inorganic moiety Cu6X6 is linked with four 2,4,6-triallyl- oxy-1,3,5-triazine molecules. The ligand molecule is coordinated to one CuII atom through the nitrogen atom of the triazine cycle and to two CuI atoms through the C=C bonds of two allyl groups. The Br content equal to 0.57 in the X(4) position linking the CuI and CuII atoms differs markedly from a value of 0.85–0.91 for the X(1), X(2), and X(3) positions linked only with the Cu(I) atoms.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 6, 2005, pp. 455–461.Original Russian Text Copyright © 2005 by Goreshnik, Schollmeyer, Mys’kiv.  相似文献   

14.
The results of measurements of the starionary and time-resolved flurescence anisotropy and of the AM1 and INDO/S calculations were used for conformational analysis of a neutral molecule of the 2-(3′-pyridyl)oxazole series and of its N-ethyl cation. Most probably, the excitation of the quasi-planar rotamers of the cation, in contrast to the neutral molecule, is accompanied by a ∼90° turn of its Et-py fragment with the formation of a twisted charge-transfer conformation. According to the data obtained for ethanol and glycerol solutions and for the poly(methyl methacrylate) matrix at 20°C, the efficiency of the intramolecular relaxation is independent of the viscosity.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 836–840.Original Russian Text Copyright © 2005 by Volchkov, Dem’yanov, Rusalov, Syreishchikova.  相似文献   

15.
Density ρ, isothermal compressibility βТ, and thermal expansion coefficient α are measured with high accuracy at 15 and 25°C for water-n-octane-sodium dodecyl sulfate-n-pentanol microemulsions with a water/oil weight ratio varying from 0.05 to 4. The internal pressure of the microemulsions is shown to be calculable from the results of dilatometric measurements. The phenomenon of temperature inversion is revealed for the temperature coefficient of internal pressure ΔP iT of the microemulsions. The analysis of this coefficient makes it possible to distinguish between three regions of the structural state in the microemulsions and a continuous structural transition in the associated microemulsions.__________Translated from Kolloidnyi Zhurnal, Vol. 67, No. 4, 2005, pp. 479–484.Original Russian Text Copyright © 2005 by Kartsev, Shtykov, Shtykova.  相似文献   

16.
The influence of plasticizers, dibutyl phthalate and triphenyl phosphate, on the structure of the surface of cellulose triacetate films was studied. The parameters of an infinite cluster of the cellulose triacetate molecules on the film surface, the correlation radius ξ of the spatial distribution of density, the degree ρs of surface filling of the cluster, and the fractal dimensionality D, were calculated from the electron-microscopic data, using the cluster model.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005, pp. 306–309.Original Russian Text Copyright © 2005 by Novikov, Varlamov, Mnatsakanov.  相似文献   

17.
The structures of a complex multicomponent Co-Mo-Fe-Bi-K-Sb-O catalyst for the oxidation of propylene to acrolein and simpler catalysts from which some catalyst components were absent were studied by X-ray diffraction analysis. The phases of α-CoMoO4, β-CoMoO4, Fe2(MoO4)3, Bi2O3 ⋅ MoO3, Bi2O3 ⋅ 2MoO3, Bi2O3 ⋅ 3MoO3, oxidized molybdenum oxide, and reduced molybdenum oxide are the main components of the catalyst. Ternary compounds were not detected. Under catalytic reaction conditions, the relative amounts of the phases changed; this change suggests the occurrence of redox transformations with the participation of these phases, probably, at the interface.__________Translated from Kinetika i Kataliz, Vol. 46, No. 4, 2005, pp. 580–584.Original Russian Text Copyright © 2005 by Shashkin, Udalova, Shibanova, Krylov.  相似文献   

18.
4-R-3,5-Dioxabicyclo[5.1.0]octanes were prepared in good yields by reduction of the corresponding 8,8-dichloro derivatives in a system Li-t-BuOH. According to the data of dynamic 1H and 13CNMR spectroscopy involving experiments in the NOESY mode the formal (R = H) at −93°C in (CD3)2CO exists in nearly equally occupied chair forms with endo- and exo-oriented three-membered ring. The like structure were found in the diastereomeric 4-Me(t-Bu)-analogs. The characteristic feature of 13C NMR spectra consists in considerable difference in the chemical shifts of the C8 atoms (Δδ∼16–17 ppm). The data on epimerization of diastereomers and calculations along AM1 procedure suggest for formal a three-component equilibrium including a twist-form.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 2, 2005, pp. 301–305.Original Russian Text Copyright © 2005 by Fedorenko, Baryshnikov, Khairutdinov, Vafina, Shtyrlin, Klochkov, Klimovitskii.  相似文献   

19.
Averaged spectra and oscilloscope traces of emission of laser plasma in vacuum produced by the impact of neodymium laser radiation (τ = 20 ns, λ = 1.06 µm, f = 12 Hz, W =108–109 W/cm2) on Pb, Ga, and polycrystalline PbGa2S4 targets were studied. From spectroscopic diagnostic data, the electron temperature, the recombination time of singly charged ions, and the number density of electrons in the laser plume of lead gallium sulfide were determined. An analysis of the results is given.__________Translated from Khimiya Vysokikh Energii, Vol. 39, No. 5, 2005, pp. 396–400.Original Russian Text Copyright © 2005 by Shuaibov, Chuchman.  相似文献   

20.
The properties of monolayers spread at the air-water interface were measured for saturated, unsaturated, and hydroxy fatty acids, differing in the type and degree of unsaturation, geometric isomerism, and position of unsaturated and hydroxy groups. Surface vapor pressures, reflecting the equilibrium between “gaseous” and “liquid” monolayer states were determined, as were the free energies of compression, ΔFc, from essentially infinite dilution (100,000 Å2/molecule) to the area per molecule, Ae at the equilibrium spreading pressure, πe. Surface vapor pressures and free energies of compression for saturated and unsaturated fatty acids with a double bond, or bonds, change in a manner expected because of chain-chain interactions. Hydroxy and acetylenic acids produce relatively high surface vapor pressures, despite their tendency for strong chain-chain interaction. It is concluded that chain-water interactions are very significant for the acetylenic and hydroxy acids and less so for the saturated and ethylenic acids.  相似文献   

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