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1.
11(16)-Dehydrolupaninium perchlorate monohydrate, [C15H23N2O]+ClO4·H2O, was obtained from 12-dehydrolupanine, the product of mercuric acetate dehydrogenation of lupanine. It forms orthorhombic crystals, space groupp212121,a=8.528(1),b=12.335(1),c=32.928(3) Å,V c=3463.8 Å3,Z=8,D m=1.34,D x=1.34 g cm–3, (CuK)=20.7 cm–1.F(OOO)=1472, mp=458 K; the finalR=0.086 for 2363 observed counter reflections. Two independent perchlorate anions and two independent cations are disordered. The conformations of the independent cations are similar: sofa (ringA), chair (ringB), intermediate between sofa and half-chair (ringC), and half-chair (ringD). The two lactam oxygens of the two independent cations are each hydrogen bonded to a different water molecule. From X-ray analysis and IR spectra in the condensed phase and13C-NMR measurements in DMSO-2H6 and2H2O it is evident that in the crystalline state as well as in solution, the immoniumlactam molecular structure is present in the compound studied.  相似文献   

2.
The compound [Cu(biz)2(N3)](ClO4) (biz = 2,2-bi-imidazoline) has been synthesized and characterized by X-ray crystallography and infrared spectroscopy. In addition, EPR and magnetic measurements have been performed. The compound crystallizes in the monoclinic space group P21/c, with a = 9.2716(2), b = 27.6454(4), c = 7.4285(1) Å, = 102.1417(6)°, V = 1861.46(5) Å3, and Z = 4. The coordination geometry around the Cu(II) ion is distorted square pyrimidal, with 4 nitrogen atoms of 2 bis-chelating ligand molecules in the basal plane and one nitrogen of the azide molecule in the apical position. The perchlorate ion is noncoordinating. In the infrared the vibrations of the coordinated azide anion are observed at 2050, 1286, and 620 cm–1, while the vibrations of the free perchlorate anion are observed at 1071, 1035, and 919 cm–1; Cu—N vibrations are observed at 418 and 336 cm–1. The molecules are connected in the lattice via relatively strong hydrogen bonding between the N—H groups at the back of the biz ligand and the N1 and N3 atoms of the azide ligand forming layers. No intermolecular magnetic interaction was observed for this compound.  相似文献   

3.
The title compound [RhCl2(SNC3H3)4] [ClO4]·CH3CN is monoclinic, witha=23.791(4),b=7.253(2),c=14.498(2)Å,=105.24(1)°,V=2414(1)Å3,Z=4,D x =1.802,(MoK)=13.95 cm–1,F(000)=1304,T=298K in space group Cc. The structure was solved by heavy atom and Fourier methods and refined toR=0.047 for 4742 unique observed reflections. The cation is nearly octahedral, with thecis andtrans angles about the Rh in the range from 89.2(2) to 90.8(2)° and 179.4(2) to 180.0(2)°, respectively. Average Rh-Cl and Rh-N bond lengths are 2.337(2) and 2.036(6)Å. One of the thiazole ligands showed disorder between the S and one of the C atoms in the ring.  相似文献   

4.
The crystals of the title compound are monoclinic, space groupP21/c witha=9.014(1),b=9.8668(5)c=17.5000(3) Å,=91.50(1)°,V=1556(1) Å3. The structure was determined by Patterson methods and refined by least squares toR=0.038 for 3829 observed reflections and 224 parameters. There are two tungsten dimers in the unit cell, each formed by a bridging oxygen lying on a center of symmetry. Each tungsten has five more coordination sites; two occupied by terminal oxygens and the remaining three by citrate oxygens. Waters of crystallization are distributed throughout the cell and together with various of the anion oxygens, make the sodium cations either five-or six-coordinate.  相似文献   

5.
Single-crystal X-ray diffraction studies have been performed on the complex cis-diaqua-bis(1,3-dimethylpteridine-2,4(1H,3H)-dione-O4,N5) copper(II) perchlorate monohydrate, [Cu(DLM)2(H2O)2](ClO4)2 · H2O. This compound crystallizes in the orthorhombic system, P212121 space group, Z = 4 with a = 8.749(1) Å, b = 14.213(1) Å, c = 21.200(2) Å, and V = 2636.2(4) Å3. The metal ion is surrounded in octahedral geometry by two mutually quasi-perpendicular N5,O4-coordinated lumazine chelators with the O4 atoms trans and the N5 atoms cis. The polyhedron is completed by two cis-coordinated water molecules. The absolute configuration of the complex can be described, following Bailar's nomenclature, as the enantiomer of the stereoisomer 4M. A three-dimensional hydrogen-bond network is defined by water molecules, perchlorate anions, and the O2 of the pteridine A.  相似文献   

6.
Crystal structures of 5-(5-methylthien-2-yl)-2-deoxyuridine (I), 5-(5-thien-2-yl)-2-deoxyuridine (II) and 5-(5-bromothien-2-yl)-2-deoxyuridine (III) have been obtained from data collected on a four-circle Enraf-Nonius diffractometer (CAD-4 system). Space group, unit/cell parameters and finalR indices are:I, monoclinic,P21,a=9.105(2),b=20.819(2),c=7.932(2) Å, =98.79(2)°,R=5.7%;II, monoclinic,P21,a=8.720(4),b=20.793(4),c=7.884(4) Å, =95.06(2)°,R=5.8%;III, monoclinic,P21,a=9.260(2),b=41.655(7),c=7.926(2) Å, =97.996(13)°,R=9.4%. Structural properties of the title compounds are compared with those of 5-(5-chlorothien-2-yl)-2-deoxyuridine (IV) previously reported in order to explain their affinity for HSV-1 thymidine kinase and their eventual interaction with viral DNA polymerase. The main structural features observed are the coplanarity of the uracil and thienyl cycles stabilized by a S–O intramolecular interaction and the formation of dimeric intermolecular H bonds between two uracil moieties.  相似文献   

7.
The crystal structure of [Co(C3H9N2O)2]ClO43H2O was established by single-crystal X-ray diffraction techniques. The compound crystallized in the monoclinic space group P21 with unit cell dimensions a = 6.715(2) Å, b = 12.097(3) Å, c = 9.904(3) Å, = 100.80(3), and z = 2. The final R value for 1359 reflections was 0.039. The 1,3-diamino-2-propanolato ligands are tridentately coordinated to cobalt atoms that have slightly distorted octahedral coordination. The five-membered chelate rings exhibit conformations between pure twist and pure envelope, while the six-membered ring adopts a boat confirmation.  相似文献   

8.
A new monomeric copper(II) complex with 2,2-bipyridine (bpy) and betaine (bet), [Cu(byy)(bet)2(H2O)](ClO4)2 · H2O, has been prepared and characterized by X-ray crystallography. The complex crystallizes in the triclinic space groupP-1 witha=8.859(2),b=11.191(2),c=14.850(3) Å, =91.41(1), =97.19(1), =91.97(1)°,V=1459.2(7) Å3, andZ=2. The structure comprises discrete cations [Cu(bpy)(bet)2(H2O)]2+ in which the metal atom is coordinated in a distorted square-pyramidal environment by two oxygen atoms from a pair of monodentate carboxylato ligands [Cu–O=1.950(2) Å] and two nitrogen atoms of a bidentate bpy ligand [Cu–N=1.997(3)–2.005(3) Å] on the basal plane, and one aqua [Cu–O=2.267(3) Å] ligand at the apical position.  相似文献   

9.
The title compound has been synthesized and its crystal structure has been solved at room temperature. It crystallizes in the triclinic system, space groupP, witha=7.853(1) Å,b=10.177(1) Å,c=13.651(4) Å,=74.57(1)°,=88.49(1)°, =80.675(4)°, andZ=2. The structure consists of isolated [Cu(bipy)2N3]+ cations (bipy=2,2-bipyridine) and perchlorate anions. The metallic cation environment has a distorted trigonal-bipyramidal geometry. The EPR spectrum is rhombic, which indicates that the distortion with respect to the perfect trigonal bipyramid is sufficiently pronounced to mixz 2- andx 2y 2-type orbitals in the ground state. The temperature dependence of the molar magnetic susceptibility has been investigated in the 300-2.2 K temperature range.  相似文献   

10.
The title compound crystallizes in the monoclinic space groupP21/a,a=11.50(2),b=7.724(1),c=12.599(3) Å,=102.22(5)°,Z=4. The structure was solved by direct methods and refined by full-matrix least squares toR=0.049 for 1032 observed reflections. The cobalt atom is -bonded to the cyclopentadienyl ring, with a mean Co-C distance of 2.07(1) Å, and also -bonded to the cyclonoatetraene ring at C(2)-C(3) and at C(6)-C(7), with a mean Co-C distance of 2.00(1) Å.  相似文献   

11.
12.
A series of ternary complexes of copper(II), cobalt(II) and zinc(II) with L-histidine, 1,10-phenanthroline, 2,2-dipyridyl or imidazole having perchlorate or acetate as counterions were synthesized and characterized by conventional methods and for [Cu(bipy)(L-hist)]ClO4·1.5H2O and X-ray crystal structure was determined. The crystals belong to the monoclinic space groupC2 witha=18.843(3),b=10.582(2),c=11.020(2), =115.20(10)°,Z=4,R=0.0535. The structure is consistent of [Cu(bipy)(L-hist)]+ cations, perchlorate ions and water molecules. The geometry around copper is trigonal bipyramidal with one N,N,O tridentate L-histidine molecule and one 2,2-dipyridyl ligand, the apical sites are occupied by the -amino nitrogen [Cu–N(71) 1.995(8)] and by N(11) of 2,2-dipyridyl [Cu–N(11) 1.983(7)], the equatorial plane is formed by the N(3) imidazole -nitrogen [Cu–N(3) 2.140(6)], O(82) carboxylic oxygen [Cu–O(82) 2.009(5)] and N(22) [Cu–N(22) 2.010(7)].  相似文献   

13.
[C16H27N2O2]+·C1O 4 ·1/2H2O,M r =387.86, is monoclinic:P21,a=8.934(1),b=14.625(1),c=14.449(1) Å, =103.03(1)°,V c =1839.3(2) Å3,Z=4,D x =1.40(1) g cm–3, (CuK)=1.54178 Å,(CuK)=20.29 cm–1,F(000)=808 e,T=292K,R=0.057 for 3428 observed reflections. Two independent cations are connected into chains along [101] by short hydrogen bonds between their oxygen atoms O(C2) and O(N16); distances, 2.607(5) and 2.625(5) Å. The water molecule has short contacts with the two independent perchlorate anions, which indicates that the anions are linked by weak hydrogen bonds utilizing the water molecule. The conformations of the two independent cations are similar and can be described as distorted half-chair, chair, distorted boat, and chair for ringsA, B, C, andD, respectively. Except for the flexible ringA, few changes in conformation of the cations are observed in comparison to the cations of lupanineN(16)-oxide perchlorate or 17--meth-yllupanine perchlorate.  相似文献   

14.
The crystal structures of ( 5-C5H4COMe)M(CO)3Me (M=Mo,W) have been determined. They are not isostructural. M=Mo isP21/c,a=10.205(6),b=14.192(8),c=8.135(6) Å,=93.43(4)° andD(calc)=1.71 g cm–3 forZ=4. M=WisP21/c,a=12.580(7),b=6.830(5),c=13.750(7) Å,=93.72(4)° andD(calc)=2.20 g cm–3 forZ=4. Both have a four-legged piano stool geometry with the substituted carbon making the closest M-C( 5) approach. The methyl group in the M=W derivative is disordered between twotrans-ligand positions. The average bonding parameters for the more accurately determined Mo analog are: Mo-C()5)=2.34(3) Å, Mo-CO=1.98(2) Å, Mo-Me=2.304(4) Å.  相似文献   

15.

Obituaries

Kirill Sergeevich Aleksandrov (January 9, 1931–July 10, 2010)  相似文献   

16.
The molecular and crystal structure of N(16)-methyl-2-oxo--isosparteine iodide monohydrate have been determined by single crystal X-ray analysis using diffraction data collected on a diffractometer. The finalR for 1211 reflections and 196 parameters was 0.036. The configuration on the parent base, 2-oxo--isosparteine, remains unchanged after methyl substitution at thecisoidally oriented N(16) tertiary amino nitrogen. Because of an internal stress, four rings of the quaternary cation adopt a distorted conformation. The water molecule of crystallization links cation and anion by O(lactam)H-O-HI hydrogen bonds. Weak C-HI interactions between the ions have been found in the crystal. Both the cation conformation and cation-anion interactions influence the position and shape ofv CH bands in the IR spectrum of solid. The methyl C-H stretching vibrations are observed at 3090 and 3025 cm–1, and the methylene absorption is observed in the region 3000-2800 cm–1. Thev OH water molecule absorption at 3490 and 3420 cm–1 indicates two types of hydrogen bonding.  相似文献   

17.
The first high-spin iron(III) compound with the ligand 2,2-bipyridine-1,1-dioxide (abbreviated as bpdo) is reported. The compound [Fe(bpdo)3](ClO4)3(CH3CN)2 crystallizes in the space group P , with a = 11.767(3), b = 13.166(4), c = 15.951(4) Å, = 104.62(3), = 101.66(3), = 112.14(3)°, and Z = 2. The Fe(III) atom is octahedrally surrounded by six oxygen atoms of three bpdo ligands. In the far-infrared region the Fe—O vibration is observed at 411 cm–1. The magnetic susceptibility reveals a of 6.04 ± 0.04 BM in the 10–280 K region, typical of high-spin Fe(III).  相似文献   

18.
19.
The crystal and molecular structure of [Zn(phen)(S2P(OiPr)2)2] (Phen = 1,10-phenanthroline) has been determined by X-ray crystallography. It crystallizes in the Monoclinic system, space group C2/c, with lattice parameters a = 19.315(4), b = 10.438(2), c = 16.567(3)Å, = 102.89 (3)°, and Z = 4. The complex has C2 symmetry. The coordination geometry of each Zn atom, by two S atoms from two (O,O-diisopropyldithiophosphato) anions and by two N atoms from phenanthroline ligand, is that of a slightly distorted tetrahedron [Zn—S 2.2914(8)Å Zn—N 2.111(2)Å]. The Zn···S distances to the noncoordinated S atoms are long: 3.5276 Å, which are indicated that there are much weaker interactions between them.  相似文献   

20.
We have analysed in detail the effect of silver-content on the optical properties of Ag-photodoped amorphous (As0.33S0.67)100?xTex (with x = 0, 1, 5 and 10 at.%) chalcogenide thin films; the chalcogenide host layers were prepared by vacuum thermal evaporation. Films of composition Agy[(As0.33S0.67)100?xTex]100?y, with y ? 18 at.%, were successfully obtained by successively photodissolving about 20- or 40-nm-thick layers of silver. The optical constants (n, k) have been accurately determined by an improved envelope method [J.M. González-Leal, R. Prieto-Alcón, J.A. Angel, D.A. Minkov, E. Márquez, Appl. Opt. 41 (2002) 7300], based on the two envelope curves of the optical-transmission spectrum, obtained at normal incidence. The dispersion of the refractive index of the Ag-photodoped chalcogenide films is analysed in terms of the Wemple–DiDomenico single-effective-oscillator model: n2(?ω)=1-EoEd/(Eo2-(?ω)2), where Eo is the single-oscillator energy, and Ed the dispersion energy. We found that the refractive index of the Ag-doped samples strongly increases with the Ag-content, whereas the optical band gap, Egopt, decreases also notably. For instance, in the particular case of x = 10 at.%, the largest Te-content, Egopt decreases from 2.17 down to 1.67 eV. It should also be mentioned that, in the case of the undoped samples, when the Te-concentration increases from zero up to 10 at.%, the value of Egopt decreases from 2.49 down to 2.17 eV.  相似文献   

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