共查询到20条相似文献,搜索用时 46 毫秒
1.
K. É. Miminoshvili A. N. Sobolev É. B. Miminoshvili L. A. Beridze É. R. Kutelia 《Journal of Structural Chemistry》2005,46(3):560-565
X-ray structural analysis has been performed for two complex compounds: Cu(en)2(o-HB)2H2O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) Å3, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)2(OH2)2]2+(o-AB?)2 (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) Å3, P21/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment. 相似文献
2.
N. N. Smirnova A. V. Markin V. A. Ruchenin S. N. Titova E. A. Gorina L. V. Kalakutskaya G. A. Domrachev A. M. Ob”edkov S. Yu. Ketkov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(6):854-860
The temperature dependence of the heat capacity C p o of the [(Me3Si)7C60]2 fullerene complex was measured for the first time using precision adiabatic vacuum calorimetry over the temperature range 6.7–340 K and high-accuracy differential scanning calorimetry at 320–635 K. For the most part, the error in the C p o values was about ±0.5%. An irreversible endothermic effect caused by the splitting of the dimeric bond between fullerene fragments and the thermal decomposition of the complex was observed at 448–570 K. The thermodynamic characteristics of this transformation were calculated and analyzed. Multifractal analysis of the low-temperature (T < 50 K) heat capacity was performed, and conclusions were drawn concerning the character of the heterodynamicity of the structure. The experimental data obtained were used to calculate the standard thermodynamic functions C p o (T), H o (T) ? H o (0), S o (T) ? S o (0), and G o (T) ? H o (0) over the temperature range from T → 0 to 445 K and estimate the standard entropy of formation of the compound from simple substances at 298.15 K. The standard thermodynamic properties of [(Me3Si)7C60]2 are compared with those of the (C60)2 dimer, the [(η6-Ph2)2Cr]+[C60]?? fulleride, and the initial C60 fullerene. 相似文献
3.
L. Mei J. Li Z. S. Ming L. Q. Rong L. X. Liang 《Russian Journal of Coordination Chemistry》2009,35(12):871-873
The treatment of o-diaminobenzene with Zn ( OAc )2 · 2H2O in alcohol results in the formation of mononuclear bis(o-diaminobenzene)diacetate Zinc, Zn[C8H11N2O2]2. Its structure was determined by X-ray diffraction analysis. The complex is also characterized by elemental analysis, 1H NMR and IR. The crystal is monoclinic space group C2, parameters: a = 16.297(5), b = 4.775(3), c = 11.664(5) Å, β = 97.646(5)°, λ = 1.54184 Å, V = 899.6(7) Å3, Z = 2, ρ c = 1.476 g/cm3, M r = 399.75, F(000) = 416.0, R 1 = 0.0594, wR 2 = 0.1439 for 995 observed reflections with I > 2σ(I). 相似文献
4.
V. V. Gavrilov M. N. Shamsutdinov G. A. Chmutova R. M. Vafina Yu. G. Shtyrlin V. V. Klochkov E. N. Klimovitskii 《Russian Journal of Organic Chemistry》2007,43(12):1846-1853
Spiro[cyclohexane-1,4′-[3,5]dioxabicyclo[5.1.0]octanes] were synthesized, and their conformational behavior was studied by dynamic 13C NMR spectroscopy. Anancomeric displacement of conformational equilibrium toward two nonequivalent twist conformers with close energies was revealed. The relative Gibbs energies ΔG o and enthalpies of formation ΔH o of twist and chair-like conformers with endo and exo orientation of the three-membered ring of structurally related formaldehyde and acetone acetals were calculated in terms of the density functional theory at the B3LYP/6-31G(d,p) level. Like spiro-cyclohexane analogs, they were shown to have a non-chair conformation. 相似文献
5.
O. V. Andreeva B. F. Garifullin A. T. Gubaidullin V. A. Al’fonsov V. E. Kataev D. V. Ryzhikov 《Journal of Structural Chemistry》2007,48(3):540-546
Crystalline inclusion complexes of diterpenoid isosteviol (ent-16-ketobeyeran-19-oic acid) with individual benzene, o-, m-, p-xylenes, ethylbenzene, isopropylbenzene, o-and m-nitoranilins, benzaldehyde, styrene and naphthalene are obtained and characterized by single crystal X-ray diffraction. As determined by GC and 1H NMR spectroscopy, isosteviol selectively includes toluene from the equimolar benzene-toluene mixture, o-xylene from a commercial mixture of xylenes, o-and m-nitroanilins from their mixture with p-nitroanilin, and also styrene from styrene-ethylbenzene and styrene-isopropylbenzene mixtures thus yielding crystalline inclusion complexes. 相似文献
6.
K. Kratzl W. Schäfer P. Claus J. Gratzl P. Schilling 《Monatshefte für Chemie / Chemical Monthly》1967,98(3):891-904
o-Methoxyphenols withp-side chains labelled with14C at the α-C-atoms were synthesized and mildly oxygenated in dilute aqueous NaOH (0.2n, 1–2 mole equivalents NaOH) at 70° C. Derivatives with α-C-atoms in different states of oxidation exhibit different reaction patterns. In contrast top-alkyl-substitutedo-methoxyphenols which dimerize too,o′-dihydroxybiphenyls, eliminations of side chains according to theDakin reaction could be observed in the case of α-carbonyl, and α-carbinol derivatives, respectively. The carbon dioxide formed in the course of oxidation of models labelled with14C in α-position proved to be inactive and does definitely not originate from α-C-atoms. Possible reaction mechanisms are discussed, and to the importance of these particular elimination reactions in lignin chemistry is referred to. 相似文献
7.
B. B. Tumataeva B. K. Kasenov S. Zh. Davrenbekov E. S. Mustafin Zh. I. Sagintaeva Sh. B. Kasenova S. T. Edil’baeva 《Russian Journal of Inorganic Chemistry》2009,54(1):27-29
Ytterbium alkali-metal chromites YbMCr2O5 (M = Li, Na, K, Cs) were synthesized by a ceramic procedure from the corresponding oxides and carbonates. Their crystal systems and unit cell parameters were determined by the homology method: for YbLiCr2O5, a = 10.34 Å, b = 10.62 Å, c = 15.05 Å, Z = 16, V o = 1653.74 Å3, ρX-ray = 5.85 g/cm3, ρpycn = 5.81 ± 0.03 g/cm3; for YbNaCr2O5, a = 10.30 Å, b = 10.56 Å, c = 16.46 Å, Z = 16, V o = 1790.32 Å3, ρX-ray = 5.64 g/cm3, ρpycn = 5.59 ± 0.07 g/cm3; for YbKCr2O5, a = 10.33 Å, b = 10.63 Å, c = 19.93 Å, Z = 16, V o = 2188.47 Å3, ρX-ray = 5.95 g/cm3, ρpycn = 5.91 ± 0.03 g/cm3; and for YbCsCr2O5, a = 10.34 Å, b = 10.63 Å, c = 18.43 Å, Z = 16, V o = 2025.72 Å3, ρX-ray = 5.19 g/cm3, ρpycn = 5.16 ± 0.05 g/cm3. 相似文献
8.
A. A. Bessonov N. B. Morozova P. P. Semyannikov S. V. Trubin N. V. Gel’fond I. K. Igumenov 《Russian Journal of Coordination Chemistry》2008,34(3):186-189
Dimethylgold(III) complexes with 8-hydroxyquinoline Me2Au(Ox) (I) and 8-mercaptoquinoline Me2Au(Tox) (II) were synthesized and studied. Complex II obtained for the first time was identified from the elemental analysis, IR, 1H NMR, and mass spectrometry data. The thermal properties of complexes I, II in condensed state were investigated by thermography. The temperature dependences of the saturated vapor pressure over crystals were measured by the Knudsen effusion method with mass spectrometric recording of the gas phase composition and the thermodynamic characteristics of the sublimation process were determined: for I, log P[Torr] = (14.6 ± 0.3) ? (6.34 ± 0.10) × 103/(T, K), Δ H subl o = 121.2 ± 1.9 kJ?1, Δ S subl o = 224.1 ± 4.6 J mol?1 K?1 (the temperature interval under study 80–115°C); for II, log P [Torr] = (13.3 ± 0.2) ? (6.30 ± 0.09) × 103/(T, K), Δ H subl o = 120.5 ± 1.7 kJmol?1, ΔS subl o = 199.3 ± 3.0 J mol?1 K?1 (86–145°C). 相似文献
9.
C. Peiffert C. Nguyen-Trung D. A. Palmer J. P. Laval E. Giffaut 《Journal of solution chemistry》2010,39(2):197-218
B-Nb2O5 was recrystallized from commercially available oxide, and XRD analyses indicated that it is stable in contact with solutions over the pH range 0 to 9, whereas solid polyniobates such as Na8Nb6O19?13H2O(s) appear to predominate at pH>9. Solubilities of the crystalline B-Nb2O5 were determined in five NaClO4 solutions (0.1≤I m /mol?kg?1≤1.0) over a wide pH range at (25.0±0.1)?°C and at 0.1 MPa. A limited number of measurements were also made at I m =6.0 mol?kg?1, whereas at I m =1.0 mol?kg?1 the full range of pH was also covered at (10, 50 and 70)?°C. The pH of these solutions was fixed using either HClO4 (pH≤4) or NaOH (pH≥10) and determined by mass balance, whereas the pH on the molality scale was measured in buffer mixtures of acetic acid?+?acetate (4≤pH≤6), Bis-Tris (pH≈7), Tris (pH≈8) and boric acid?+?borate (pH≈9). Treatment of the solubility results indicated the presence of four species, \(\mathrm{Nb(OH)}_{n}^{5-n}\) (where n=4–7), so that the molal solubility quotients were determined according to: and were fitted empirically as a function of ionic strength and temperature, including the appropriate Debye-Hückel term. A Specific Interaction Theory (SIT) approach was also attempted. The former approach yielded the following values of log?10 K sn (infinite dilution) at 25?°C: ?(7.4±0.2) for n=4; ?(9.1±0.1) for n=5; ?(14.1±0.3) for n=6; and ?(23.9±0.6) for n=7. Given the experimental uncertainties (2σ), it is interesting to note that the effect of ionic strength only exceeded the combined uncertainties significantly in the case of log?10 K s6 to I m =1.0 mol?kg?1, such that these values may be of use by defining their magnitudes in other media. Values of Δ f G o, Δ f H o, S o and \(C_{p}^{\mathrm{o}}\) (298.15 K, 0.1 MPa) for each hydrolysis product were calculated and tabulated.
相似文献
$0\mathrm{.5Nb}_{2}\mathrm{O}_{5}\mathrm{(cr)+0}\mathrm{.5(2}n-5\mathrm{)H}_{2}\mathrm{O(l)}_{\leftarrow}^{\to}\mathrm{Nb(OH)}_{n}^{5-n}+(n-5)\mathrm{H}^{+}\quad (n=4\mbox{--}7)$
10.
Z. M. Chen S. P. Wang N. Yang N. Zhao J. J. Zhang R. F. Wang B. H. Zhao 《Russian Journal of Coordination Chemistry》2009,35(7):541-546
Ternary rare-earth complexes with o-methylbenzoic acid (o-MBA) and 1,10-phenanthroline (Phen) Ln2(o-MBA)6(Phen)2 · nH2O(n = 0, 1) (Ln = La, Pr, Y, Yb) were synthesized and characterized by elemental analysis, IR, X-ray diffraction, and TG-DTG means. The complex La2(o-MBA)6(Phen)2 · H2O (I) is composed of two species of binuclear molecules in which the La3+ ion is coordinated with two nitrogen atoms of Phen and seven oxygen atoms of carboxylate groups. The carboxylate groups were bonded to La3+ in three modes: chelating-bidentate, bridging-bidentate, and chelating-bridging tridentate. The La3+ ion adopted a vigorous distorted monocapped square antiprism geometry. Complex I belongs to the triclinic crystal system, P space group, lattice parameters: a = 13.058(3), b = 12.7584(11), c = 20.773(4) Å, α = 101.18(3)°, β = 93.88(3)°, γ = 115.82(3)°, V = 3283.0(11)Å3, Z = 2, ρcalcd = 1.484 mg/m3, M r = 1467.06, F(000) = 1476, μ = 1.350 mm-1. The structure was refined to R l = 0.0631 and wR 2 = 0.1504. The antibacterial activity test indicates that these complexes exhibit better antibacterial ability against Escherichia coli and Staphylococcus aureus than the corresponding rare-earth chloride or o-MBA. 相似文献
11.
T. M. Polyanskaya K. A. Khaldoyanidi A. I. Smolentsev 《Journal of Structural Chemistry》2010,51(2):327-334
The crystal structures of catechol (o-dihydroxybenzene) and its 2:1 complex with dimethylsulfoxide are determined at T = 150 K. Crystal data: C14H18O5S, M = 298.37, triclinic, space group P \(\bar 1\), unit cell parameters: a = 7.7285(13) Å, b = 9.9924(17) Å, c = 10.3188(18) Å, α = 89.963(4)°, β = 89.968(4)°, γ = 69.076(5)°, V = 744.3(2)Å3, Z = 2, D x = 1.331 g/cm3, R1 = 0.048; C6H6O2, M = 110.11, monoclinic, space group P21/n, a = 9.8206(6)Å, b = 5.5903(3)Å, c = 10.4439(6)Å, β = 114.952(2)°; V = 519.85(5) Å3, Z = 4, D x = 1.407 g/cm3, R1 = 0.0289. In the 2:1 complex the molecules are joined in a supramolecular ensemble by D-H...A hydrogen bonds (D = O, C; A = O, π); in catechol they are bonded only by O-H...O. The state diagram of the catechol-dimethylsulfoxide system is examined by DTA. 相似文献
12.
L.I. Kas'yan I.N. Tarabara Ya.S. Bondarenko S.V. Shishkina O.V. Shishkin V.I. Musatov 《Russian Journal of Organic Chemistry》2005,41(8):1122-1131
Establishing of the structure of hydrazinolysis product obtained from bicyclo[2.2.1]hept-2-ene-endo-5, endo-6-dicarboxylic (endic) acid was performed by preparation of the compound under alternative conditions followed by comparison of the characteristics and spectral parameters of the resulting substances, and also by quantum-chemical calculations by the density functional method of the chemical shifts in 1H and 13C NMR spectra of different reaction products. The X-ray diffraction analysis of the hydrazide was also carried out. The compound obtained was assigned a structure of N-aminobicyclo[2.2.1] hept-2-ene-endo-5,endo-6-dicarboximide. The products were prepared by its reactions with arylsulfonyl chlorides, benzoyl chlorides, m-tolyl and p-toluene-sulfonyl isocyanates, phenyl isothiocyanate, with o-nitrobenzaldehyde, and oxiranes (1,2-epoxycyclohexane and 2,3-epoxypropylcarbazole). The aromatic sulfonamides, carboxamides, and ureas were epoxidized by performic acid obtained in situ from the formic acid and hydrogen peroxide. Products of [3+2]-cycloaddition of aryl azides to the strained double bond in the N-aminobicyclo[2.2.1] hept-2-ene-endo-5,endo-6-dicarboximide and its derivatives. The structures of compounds obtained were confirmed by their IR, 1H and 13C NMR spectra. 相似文献
13.
Using emulsion dispersive liquid–liquid microextraction preconcentration and injection of a large volume of an extract (10 μL), the limits of chromatographic–mass spectrometric detection of o-phthalic acid esters in water have been attained at the level 4 × 10–6–1 × 10–5 mg/L. The main source of the systemic error of the determination of impurities was found to be the release of o-phthalates from microparticles of chromatographic septum to the carrier gas. The extractant (n-octane) was purified by Rayleigh distillation. The independence of the concentration coefficient of the studied o-phthalates of concentration in the range (0.4–30) × 10–4 mg/L has been demonstrated. The relative expanded uncertainty of the determination of o-phthalates has been calculated and equals 12–39%. 相似文献
14.
Zyong Ngia Bang V. N. Komissarov Yu. A. Sayapin V. V. Tkachev G. V. Shilov S. M. Aldoshin V. I. Minkin 《Russian Journal of Organic Chemistry》2009,45(3):442-448
Reaction of 3,5-di-tert-butyl-1,2-benzoquinone with 5-amino-4-chloroquinolines gave derivatives of a new fused heterocyclic system, substituted quinolino[4,5-bc][1,5]benzoxazepines. The molecular structure of 9,11-di-tert-butyl-2,4,6-trimethyl-7H-quinolino[4,5-bc][1,5]benzoxazepine was determined by X-ray analysis. 3,5-Di-tert-butyl-1,2-benzoquinone reacted with o-nitro-, o-acyl-, and o-methoxycarbonylanilines and some amino-substituted nitrogen-containing heterocycles to form the corresponding sterically hindered N-aryl-(hetaryl)-o-aminophenols. Di-tert-butyl-substituted phenoxazines were obtained as a result of thermal cyclization of intermediately formed quinone imines. 相似文献
15.
Tong Li Xin-Long Yan Zhan-Wei Li Zhi-Hong Ma Su-Zhen Li Zhan-Gang Han Xue-Zhong Zheng Jin Lin 《Transition Metal Chemistry》2018,43(4):313-322
Reactions of the substituted tetramethylcyclopentadienes [C5HMe4R] [R = t Bu, Ph, CH2CH2C(CH3)3] with Mo(CO)3(CH3CN)3 in refluxing xylene gave a series of dinuclear molybdenum carbonyl complexes [(η5-C5Me4R)Mo(CO)3]2 [R = t Bu (1), Ph (2), CH2CH2C(CH3)3 (3)], [(η5-C5Me t Bu)Mo(μ-CO)2]2 (4)], and [(η5-C5Me4) t Bu]2Mo2O4(μ-O) (5)], respectively. Complexes 1–5 were characterized by elemental analysis, IR, 1H NMR, and 13C NMR spectroscopy. In addition, their crystal structures were determined by X-ray crystal diffraction analysis. The catalytic activities of complexes 1–3 in Friedel–Crafts acylation in the presence of o-chloranil has also been investigated; the reactions were achieved under mild conditions to give the corresponding products in moderate yields. 相似文献
16.
The structures of products formed in reactions of tert-butylated o-quinones with alkyl radicals were determined by 1H and 13C NMR and two-dimensional 1H-1H NOESY spectroscopy, and also by gas chromatography-mass spectrometry. The major products formed upon γ-irradiation of deaerated solutions of 4-tert-butyl-1,2-benzoquinone and 3,5-di-tert-butyl-1,2-benzoquinone in cyclohexane are monoalkyl ethers and products of addition to the C=C bond. In the case of 4-tert-butyl-1,2-benzoquinone, these are products of mixed O-C and C-C alkylation; the adduct formed by addition of the cyclohexyl radical to the C=C bond in 3,5-di-tert-butyl-1,2-benzoquinone gives an unsymmetrical dimer whose structure was proved by single-crystal X-ray diffraction. 相似文献
17.
A new lanthanide complex [{Sm(HPht)(Phen)(H2O)2}2(μ-Pht)2] (I), where Pht2? is dianion of o-phthalic acid; HPht? is monoanion of o-phthalic acid; Phen is 1,10-phenanthroline, has been synthesized, and its crystal structure was determined by X-ray crystallography. Complex I crystallizes in the triclinic system, space group P \(\bar 1\), with lattice parameters a = 10.1126(3), b = 10.7029(3), c = 11.9360(3) Å, α = 90.2260(10)°, β = 99.526(2)°, γ =100.9810(10)°, V = 1249.87(6) Å3, Z = 2, ρ c = 1.849 mg/m3, final R indices I > 2σ(I): R 1 = 0.0202, wR 2 = 0.0493; R indices (all data): R 1 = 0.0220, wR 2 = 0.0504. 相似文献
18.
V. Anil B. Shankar G. Bharath P. Jalapathi 《Russian Journal of General Chemistry》2017,87(11):2648-2653
A series of novel substituted bis-benzimidazole derivatives were synthesized by reaction of 5,5′-methylenebis(2-hydroxybenzaldehyde) with various substituted o-phenylenediamines in glacial acetic acid. The structure of the newly synthesized compounds was elucidated by 1H and 13C NMR, FT-IR, and MS spectra, and their antimicrobial activity against gram positive and gram negative bacteria and antifungal activity were evaluated. The thienyl-substituted derivative showed significant activity against Bacillus licheniformis. Bacillus subtilis, Staphylococcus aureus, Klebsiella pneumonia (bacteria), and Fusarium solani (fungi). The activities of the fluoro-substituted substituted derivative against some bacterial strains and of the thienyl-substituted derivative against fungi were found to be similar to those of standard drugs. 相似文献
19.
P. I. Fedorov T. P. Fedorova V. P. Sheverdov G. P. Pavlov A. V. Eremkin 《Russian Journal of Organic Chemistry》2016,52(6):806-812
Precursors to terpene alcohols of the o- and p-menthane series (o-cimen-7-ol and o- and p-cimen-9-ols) were synthesized, and their reduction with lithium in ethylenediamine was studied. The reduction of o- and p-cimen-9-ols in the presence of isopropyl alcohol selectively afforded the corresponding 1,4-dihydro derivatives. Under analogous conditions, o-cimen-7-ol was converted into a mixture of unsaturated hydrocarbons. The reduction with lithium in ethylenediamine in the absence of isopropyl alcohol in all cases gave mixtures of menthene alcohols. 相似文献
20.
V. I. Smirnov V. G. Badelin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(9):1555-1559
The integral enthalpies of solution (T = 298.15 K) of L-α-alanyl-L-α-alanine in aqueous-organic solvents (acetonitrile, 1,4-dioxane, acetone, formamide, N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, and N,N-dimethylsulfoxide) were measured at organic component concentrations x 2 = 0–0.3 mole fractions. The standard enthalpies of solution (Δsol H o) and transfer (Δtr H o) of the peptide from water into mixed solvents were calculated. The influence of the structure and properties of solutes and mixture composition on solute thermochemical characteristics is considered. The enthalpy pair interaction coefficients h xy between L-α-alanyl-L-α-alanine and organic solvent molecules were calculated. The linear Kamlet-Taft four-parameter equation was used to reveal correlation between the h xy values and the properties of organic solvents. 相似文献