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1.
Electrophilic sulfenylation, selenenation, and halogenation of bicyclo[2.2.1]heptenes containing CF3 or NO2 group in position endo-5 were studied. The sulfenylation and selenenation were accomplished by arylsulfene- and arylselenenamides activated by POHal3 (Hal = Br, Cl), and iodination was performed by KICl2. The reactions are regiospecific and involve an exo-attack of the electrophilic fragment (arylthio or arylseleno group or iodine) on the C=C bond atom located closer to the CF3 or NO2 group. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1445–1448, June, 2005.  相似文献   

2.
Two novel cobalt(III) mixed-polypyridyl complexes [Co(bpy)2(dpta)]3+ and [Co(bpy)2(amtp)]3+ (bpy = 2,2′-bipyridine, dpta = dipyrido-[3,2-a;2′,3′-c]-thien-[3,4-c]azine, amtp = 3-amino-1,2,4-triazino[5,6-f]-1,10-phenanthroline) have been synthesized and characterized. The interaction of CoIII complexes with calf thymus DNA was investigated by spectroscopic and viscosity measurements. Results suggest that the two complexes bind to DNA via an intercalative mode. Moreover, CoIII complexes have been found to promote the photocleavage of plasmid DNA pBR322 under irradiation at 365 nm. The mechanism studies reveal that hydroxyl radical (OH) is likely to be the reactive species responsible for the cleavage of plasmid DNA by [Co(bpy)2(dpta)]3+ and superoxide anion radical (O 2 •− ) acts as the key role in the cleavage reaction of plasmid DNA by [Co(bpy)2(amtp)]3+.  相似文献   

3.
Two new ruthenium(II) polypyridyl complexes (1) (dtmi = 3-(pyrazin-2-yl)-as-triazino[5,6-f]-5-methoxylisatin) and (2) (dtni = 3-(pyrazin-2-yl)-as-triazino[5,6-f]-5-nitroisatin) have been synthesized and characterized by elemental analysis, FAB-MS, ES-MS and 1H-n.m.r. The DNA-binding patterns of complexes were investigated by spectroscopic titration, viscosity measurements and thermal denaturation. The results indicate that the complexes (1) and (2) interact with calf thymus DNA (CT-DNA) by intercalative mode. Due to the withdrawing electronic substitutent in the intercalative ligand, ptni, the DNA-binding affinity of the complexes (2) is larger than that complex (1) does.  相似文献   

4.
Potassium oxosulfatovanadate(V) K3VO2(SO4)2 has been obtained by solid-phase synthesis from K2SO4, K2S2O7, and V2O5 (2: 1: 1), and its formation conditions, crystal structure, and physiochemical properties have been studied. The conversions of K3VO2(SO4)2 in contact with potassium vanadates and other potassium oxosulfatovanadates(V) are considered in terms of phase relations in the K2O-V2O5-SO3 system, which models the active component of vanadium catalysts for sulfur dioxide oxidation into sulfur trioxide. The X-ray diffraction pattern of K3VO2(SO4)2 is indexed in the monoclinic system (space group P21) with unit cell parameters of a = 10.0408(1) Å, b = 7.2312(1) Å, c = 7.3821(1) Å, β = 104.457(1)°, Z = 2, and V = 519.02 Å3. The crystal structure of K3VO2(SO4)2 is built from [VO2(SO4)2]3? complex anions, in which the vanadium atom is in an octahedral oxygen environment formed by two terminal oxygen atoms (V-O(6) = 1.605(7) Å, V-O(10) = 1.619(7) Å and four oxygen atoms of the two chelating sulfate anions. The vibrational spectra of K3VO2(SO4)2 are analyzed using these structural data.  相似文献   

5.
A novel Cu(II) complex Cu2(Endc)2(Bipy)2 has been synthesized by the reaction of Cu(NO3)2 · 3H2O, Endc (endo-norbornene-cis-5,6-dicarboxylic acid), and Bipy (2,2-bipyridine) at room temperature. Elemental analysis, IR spectra, and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure. Crystal data for this complex: triclinic, P \(\bar 1\) with a = 9.0373(10), b = 10.1637(11), c = 10.5574(12) Å, α = 65.78(1)°, β = 72.32(2)°, β = 73.23(2)°, Z = 1, V = 827.46(16) Å3, ρ c = 2.160 g/cm3, F(000) = 410.0, R = 0.0483 and wR = 0.0958 independent reflections for 4468 observed ones (I > 2 σ(I)).The Cu2+ ion is coordinated by two nitrogen atoms from the Bipy molecule and three oxygen atoms from two Endc, giving a distorted squarepyramidal coordination geometry. Two neighboring Cu2+ ions are bridged by a pair of bimonodentate carboxyl groups of different Endc acids, giving a centrosymmetrical binuclear structure which a Cu…Cu distance of 3.2946 Å. The photoluminescence properties of the complex were studied at room temperature. The complex displays an obvious photoluminescent emission upon excitation at 390 nm in the solid state.  相似文献   

6.
The phase diagrams, isotherms of the electrical conductivity, Raman spectra, and time correlation functions of vibrational dephasing are studied for the LiN(CF3SO2)2-(CH3)2SO2 system, which is promising for use as an electrolyte in medium-temperature lithium-ion batteries. The phase diagram of this system contains a broad supercooled region. It is shown that the concentration dependences of the electrical conductivity are typical for solutions of strong electrolytes. The Raman spectra and the time correlation functions of vibrational dephasing for the anion and the solvent indicate that in the supercooling range, cations are weakly solvated by solvent molecules and form ion pairs.  相似文献   

7.
Knudsen cell mass spectrometry was used to study ion-molecular electron exchange reactions between some trifluoromethyl derivatives of C60 fullerene. Electron affinity values were experimentally determined for C60(CF3)10 and the S 6 isomer of C60(CF3)12 and compared with the results of calculations and the data in the literature.  相似文献   

8.
Vanadium(V) complexes of general composition M3VO2(SO4)2 (M = Rb, Cs) were synthesized by a solid-state route. The individuality of the synthesized compounds was proved by X-ray and neutron diffraction, vibrational spectroscopy, and microscopic analysis. The X-ray diffraction patterns of M3VO2(SO4)2 were indexed to fit the monoclinic system (space group P2/c, Z = 4) with the following unit cell parameters: a = 11.6487(2) Å, b = 8.4469(2) Å, c = 12.1110(2) Å, β = 109.483(1)°, V = 1123.43 Å3 (Rb); a = 12.0546(3) Å b = 8.7706(2) Å, c = 12.6496(3) Å, β = 109.843(2)°, V = 1257.99 Å3 (Cs). In the crystal structure of M3VO2(SO4)2, [VO2(SO4)2]3? complex anions can be discerned in which the vanadium atom is surrounded by five oxygen atoms: two oxygen atoms form short terminal V–O bonds, and three oxygen atoms are from the two sulfato groups, one of which acts as a monodentate ligand and the other acts as a bidentate chelating ligand.  相似文献   

9.
Coordination polymers [AgCF3CO2(2,3-Et2Pyz)](I)(2,3-Et2Pyz-C8H12N2) and [AgCF3CO2(Bpeta)] (II) (Bpeta is 4′4-bipyridylethane, C12H12N2) are synthesized. Their structures are determined. The crystals of compound I are monoclinic, space group P2(1)/n, a = 7.185(1), b = 14.754(1), c = 12.317(1)Å, β = 97.09(1)°, V = 1295.7(2) Å3, ρcalcd = 1.831 g/cm3, Z = 4. Structure I consists of infinite chains of doubled polymeric chains joined by silver carboxylate dimers [[Ag2(CF3CO2)2(Et2Pyz)2]. The coordination polyhedron of Ag+ is a distorted tetrahedron. The crystals of compound II are orthorhombic, space group Pbca, a = 13.555(3), b = 13.991(3), c = 16.449(3) Å, V = 3119.5(11) Å3, ρcalcd = 1.725 g/cm3, Z = 8. Doubled polymeric chains with the Ag…Ag bond (3.16 Å) are also formed in structure II. Supramolecular layers are formed in the structure due to the weak π-π-stacking interaction between the aromatic groups of chains. The CF3CO 2 ? anion is weakly bound to Ag+ (Ag-Oavg 2.790 Å).  相似文献   

10.
A new Co(III) dioxime complex with selenocarbamide was obtained by the reaction of Co(BF4)2 ? 6H2O, DmgH2, and Seu (DmgH2 = dimethylglyoxime, Seu = selenocarbamide). According to X-ray diffraction (CIF file CCDC no. 1485732), the product was an ionic coordination compound with unusual composition, [Co(DmgH)2(Seu)1.4(Se-Seu)0.5(Se2)0.1][BF4] (I). Apart from two monodeprotonated DmgH ̄ molecules, the central atom coordinates neutral Seu, Se-Seu, and Se2 molecules. Thus, the crystal contains the complex cations [Co(DmgH)2(Seu)2]+, [Co(DmgH)2(Seu)(Se-Seu)]+, and [Co(DmgH)2(Seu)(Se2)]+. Each [BF4] ̄ anion is linked to the cations not only by electrostatic forces but also by intermolecular N–H···F hydrogen bonds (H-bonds). The complex cations are combined by intermolecular N–H···O H-bonds. The new coordination compound was found to possess biological activity. Treatment of the garlic (Allium sativum L.) foliage with an aqueous solution of I optimizes the content of selenium in the leaves and cloves and enhances the growth and plant productivity. The organs of treated plants are characterized by enhanced antioxidant protection owing to increasing activity of antioxidant enzymes and contents of proline and assimilation pigments, and decreasing lipid peroxidation.  相似文献   

11.
The reaction of [RuCl2(PPh3)3] complex with dimethylpyrazole has been examined. A new ruthenium complex—[RuCl2(PPh3)2(3,5-Me2HPz)2] has been obtained and characterized by IR, 1H NMR and UV-VIS measurements. Crystal and molecular structure of the complex has been determined. The electronic structure of the complex has been calculated by TDDFT method.  相似文献   

12.
By single crystal X-ray analysis, the atomic structure of the crystals of [Eu(NO3)3(HMPA)3] complex (HMPA is hexamethylphosphorotriamide) possessing intense triboluminescence is determined. Symmetry of centrosymmetrical crystals is monoclinic: a = 13.785(1) Å, b = 19.746(2) Å, c = 14.723(1) Å, β= 102.143(2)°, P21/n space group, Z = 4, d x = 1.484 g/cm3. The crystal structure is represented by separate C18H54EuN12O12P3 complexes linked by van der Waals interactions with pronounced cleavage planes. The coordination polyhedron of Eu(III) atom reflects the state of distorted square antiprism. The possible causes of spectral differences in the Stark structure of photo- and triboluminescence are discussed.  相似文献   

13.
The sequence of phases occurring during treatment of lanthanum sulfate, La2(SO4)3 and lanthanum oxysulfate, La2O2SO4 in a hydrogen flow is established. The temperature ranges in which homogeneous La2O2S is produced are revealed: when La2(SO4)3 is a precursor, the range is 770–1220 K; in the case of La2O2SO4, the interval is 950–1220 K. The kinetic curves showing the time dependence of the yield of La2O2S is constructed and treated using the Avrami-Erofeev and contracting volume equations. The activation energies of the reactions are determined.  相似文献   

14.
The crystal structures of isostructural mixed-ligand fluorosulfate complex compounds of indium(III) M2[InF3(SO4)H2O] (M = K, NH4), formed of K+ cations, NH4 + respectively, and complex [InF3(SO4)H2O]2– anions are determined. In the complex anion, the indium atom surrounded by three F atoms, the oxygen atom of the coordinated H2O molecule, and two oxygen atoms of the bridging sulfate group forms a slightly distorted octahedron (CN 6). Via alternating bridging SO4 groups, the polyhedra of In(III) atoms are arranged in polymer chains. The O–H???F hydrogen bonds organize the chains in a three-dimensional network. The K+ and NH4 + cations are located in the structure framework and additionally strengthen it.  相似文献   

15.
We describe the preparation and crystal structures of the ionic complexes [Cu(bipy)2{ONC(CN)2}]CF3SO3 (1b), [Cu(phen)2{ONC(CN)2}]PF6 (2p) and [Cu(bipy)2{ONC(CN)2}]PF6 (2b). In the complex cations [Cu(L)2{ONC(CN)2}]+ (L is 2,2′-bipyridine (bipy) or 1,10-phenanthroline (phen)) the two molecules of bipy or phen coordinate to the copper atom through two nitrogen atoms along with the oxygen atom of the nitrosodicyanomethanide anion, ONC(CN) 2 ? , to form a {CuN4O} chromophore with a distorted square pyramidal coordination sphere in (1b) and (2b) and a distorted trigonal bipyramidal geometry in (2p). The basal plane in (1b) and (2b) is formed by an oxygen atom coordinated at the Cu1–O1 distance of 1.990(2) and 2.002(2) Å, respectively, and three nitrogen atoms coordinated to the copper atom at similar distances with the average of 2.01(2) and 2.00(3) Å, respectively. The axial position is occupied by the fourth N atom at the longer distance of 2.222(2) and 2.185(2) Å, respectively. The trifluoromethanesulfonate anion (triflate), CF3SO 3 ? , in (1b) might be considered as very weakly coordinated in the opposite axial position (Cu1–O2 = 2.719(2) Å). The equatorial plane in (2p) is formed by an oxygen atom coordinated at the Cu1–O1 distance of 1.975(3) Å, and two nitrogen atoms from different phen molecules coordinated to the copper atom at the same distance within 2 σ with the average distance of 2.124(2) Å. The axial positions are occupied by remaining two nitrogen atoms coordinated at shorter distance (average Cu–N = 1.99(3) Å). The hexafluorophosphate anions, PF 6 ? , in (2p) and (2b) remain uncoordinated. Besides the ionic forces, the structures of (2p) and (2b) may be stabilized by very weak C–H···F whereas the structure of (1b) by very weak C–H···F, C–H···O and C–H···N hydrogen bonds. The structural–spectral correlations are also discussed.  相似文献   

16.
The complex [UO2(SeO4)(C5H12N2O)2(H2O)] (I) was synthesized and studied by thermal analysis, IR spectroscopy, and X-ray crystallography. The crystals are orthorhombic: a = 13.1661(3) Å, b = 16.4420(5) Å, c = 17.4548(6) Å, Pbca, Z = 8, R = 0.0423. The structural units of crystal I are chains with the composition coinciding with that of the compounds of the AB2M 3 1 crystal chemical group of the uranyl complexes (A = UO 2 2+ , B2 = SeO 4 2? , M1 = C5H12N2O and H2O).  相似文献   

17.
A complex of uranyl perchlorate with imidazolidine-2-one as the molecular ligand, [UO2(Imon)4(H2O)](ClO4)2 (I), was synthesized and structurally characterized by X-ray diffraction analysis. The coordination number of the uranium atom is 7. The nearest environment of the uranyl ion includes four O atoms of the imidazolidine-2-one molecules and one O atom of the water molecule. The perchlorate anions are outer-sphere ligands. The crystals are monoclinic: space group P21/c; a = 16.294(3) Å, b = 16.135(3) Å, c = 9.987(2) Å, = 97.69 (3)°, V = 2603.0 (9) Å3, (calcd) = 2.117 g/cm3, Z = 4. The IR and luminescence spectra of the complex were recorded.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 919–924.Original Russian Text Copyright © 2004 by Andreev, Antipin, Budantseva, Tuchina, Serezhkina, Fedoseev, Yusov.  相似文献   

18.
Glass formation boundaries in the Al2(SO4)3-Al(NO3)3-H2O system were determined. IR spectra were studied. Schemes of structural rearrangements within the boundaries of a second glass formation region in the Al(NO3)3-H2O binary subsystem are suggested. A structure is suggested for glassy Al(NO3)3H2O.  相似文献   

19.
The hydrothermal reaction of a mixture of V2O5, VCl3, 2,5-pyridinedicarboxylic acid and diluted H2SO4 for 68 h at 180°C gives a blue colored solution which yields prismatic blue crystals of IV 2 IV O2(SO4)2(H2O)6] (1) in 32% yield (based on V). Complex 1 was investigated by means of elemental analysis (C, H and S), TGA, FT-IR, manganometric titration, Single Crystal X-ray Diffraction Methods and also comparative antimicrobial activities. Crystal data for the compound: monoclinic space group P21/c and unit cell parameters are a = 7.3850(12) Å, b = 7.3990(7) Å, c = 12.229(2) Å, β = 108.976(12)° and Z = 2. Although structure of 1 as a natural mineral has been previously determined, this work covers new preparation method and full characterization of 1 along with comparison of antibacterial activity between 1 and the commercial vanadium(IV) oxide sulfate hydrate compounds, VOSO4 · xH2O (Riedel-de Haën and Alfa Aesar brand names). 1 was evaluated for the antimicrobial activity against gram-positive, gram-negative bacteria, yeasts and mould compared with the commercial VOSO4 · xH2O compounds. 1 showed weak activity against bacteria Bacillus cereus, Nocardia asteroides and yeast Candida albicans. A good antimicrobial activity was recorded against Cirtobacter freundii (15 mm). There are only a few reproducible well-defined vanadium(IV) starting materials to use for exploring the synthesis of new materials. VCl4, VO(acac)2, VOSO4 · xH2O and [V(IV)OSO4(H2O)4] · SO4 · [H2N(C2H4)2NH2] are common starting materials for such applications. In addition to these compounds, 1 can be used as an oxovanadium precursor.  相似文献   

20.
On the basis of experimental data obtained in the study of glass-formation boundaries in the Al2(SO4)3-HIO3-H2O, Al(IO3)3-Al2(SO4)3-H2O, and Al(IO3)3-HIO3-H2O systems and using geometrical analysis, we predict the positions of glass-formation boundaries in the Al(IO3)3-Al2(SO4)3-HIO3-H2O four-component system along 60, 40, and 25 wt % H2O sections.  相似文献   

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