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1.
[W3(O)O3Cl3(C5H5N)6]2W6O19·6C5H5N, the side product of the reaction between WCl4(C5H5N)2 and pyridine, crystallizes in the rhombohedral space groupR¯3 (No. 148), witha=14.044(1) Å,=87.70(1)°, andZ=1. The structure was solved by the heavy-atom method, and refined to the unweighted and weighted residuals of 0.068 and 0.055, respectively. The tungsten atoms define an equilateral triangle with a capping and three bridging oxygen atoms. Two pyridines in thecis position and a chlorine atom form, together with the oxygens, a distorted octahedron around the tungsten atoms; three octahedra are connected through common edges. Important bond lengths are: W-W (single bond) 2.532(1), W-O (tricapped) 2.09(1), W-O (bridging) 1.92(1) and 1.94(1), W-C1 2.424(5), and W-N (pyridine) 2.23(1) and 2.26(1) Å. In W6O 19 2– , six WO6 octahedra have one common central oxygen, twelve bridging and six terminal oxygen atoms. Corresponding W-O bond lengths are: 2.323(1) (central oxygen), from 1.90 to 1.94(1) (bridging oxygens), and 1.70(2) Å (terminal oxygens). Lattice pyridine molecules have no important contacts with either anion or cation.  相似文献   

2.
The title compound (C7N2H10, HC1, 1/2H2O) crystallizes in the space groupC2/c with cell parameters:a=11.651(9),b=16.309(1),c=9.167(1)Å,=94.95(3)°,Z=8, withd=1.287 g cm–3. One of the chlorine atoms lies on a twofold axis, the second and the oxygen atom of the water molecule have disordered positions. Intermolecular interactions through hydrogen bonds are established between nitrogen atoms of the pyrazole ring and chlorine atoms or the water molecule. In this way, chains of molecules are built; these chains, through van der Waals interactions, form layers which are stacked in the a direction. The1H,13C, and15N NMR (this last using the double labelled compound) have been recorded in solution and the13C NMR spectrum also in the solid state (CP/MAS technique). The NMR parameters ( andJ's) thus obtained are discussed using the molecular structure.  相似文献   

3.
The crystal structures of (E)-5-hydroxypyrrolizidin-3-one (2) and (Z)-5-thioketalpyrrolizidin-3-one (3) have been determined by single-crystal x-ray diffraction techniques and refined by full-matrix least squares. Molecule2 crystallizes in the monoclinic space groupP21/a(No. 14) witha=7.887(3) Å,b=9.788(5) Å,c=9.316(4) Å,=100.6(1), andZ=4. Molecule 3 crystallizes in the monoclinic space groupP21/c witha=12.947(14) Å,b=10.553(14) Å,c=9.629(14) Å,=101.4(1), andZ=4. The calculated density for both molecules is 1.33 g cm–1. FinalR-factors were 5.1% for2 and 8.59% for3. The x-ray results showed that a change in configuration occurred in the reaction going from2 to3.  相似文献   

4.
The crystal structure of rubidium azidotrimethylaluminate has been determined from three-dimensional counter data, and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupP21/n, witha= 10.003(5),b=7.497(4),c= 11.806(5) Å, = 108.70(3) °, andD c= 1.58 g cm=3 forZ=4. The finalR factor for 922 observed reflections is 0.049. The compound is not isostructural with its cesium analog. The aluminum atom is coordinated in a tetrahedral fashion, and the Al-N bond length is 1.944(8) Å.  相似文献   

5.
The structure of the polymeric rhodanine compound, C6H6CuIN2O2S4, was determined by X-rays.M r =456.8, monoclinic, space groupP21/c,a=4.1947(7),b=17.6999(12),c=17.1048(8) Å,=96.15(1)°,V c =1262.6 Å3,Z=4,D c =2.40Mg m–3, CuK radiation (graphite crystal monochromator, =1.54056 Å),(CuK)=278.9 cms-1,F(000)=872,T=290 K. Final conventionalR-factor=0.029, andR w =0.044 for 2384 unique reflections and 153 variables. The structure was solved using Patterson methods andDirdif, and refined by full-matrix least-squares methods. The compound forms zigzag chains alonga. The copper atom is in trigonal pyramidal coordination, with two sulfur atoms of the thiocarbonyl group and two bridging iodine atoms. The copper-sulfur distances are 2.278(1) and 2.299(1) Å, and the copper-iodine distances are 2.657(1) and 2.814(1) Å.  相似文献   

6.
The title compound has been synthesized by the reaction of CrCl36H2O with K{S2COCH(CH3)2} in a 13 molar ratio in an aqueous medium. It has been characterized by elemental analysis and IR spectral studies. Crystals of Cr{S2COCH(CH3)2}3 are monoclinic, space group P21/n witha=10.002(2),b=10.973(1),c=18.961(6) Å,=91.78(2)°,V=2079.9 Å3,Z=4,D calc=1.46 g cm–3, monochromatic radiation (Mo-K), =0.71069 Å,=11.2 cm–1,F(0 0 0)=948,T=295K, finalR=0.0320 for 2641 reflections. The environment of the chromium atom is based on an octahedral geometry having six sulfur donor atoms from three symmetrically chelated ligands with average distances: Cr-S=2.396(9) Å, C-S=1.690(3) Å and C-O=1.315(3) Å. The bond distance between oxygen atom and the carbon atom of the isopropyl group (O-Cav=1.478(4) Å) suggests that the form –S 2 (–) C=O(+)CH(CH3)2 contributes significantly to the structure of the isopropyl group.  相似文献   

7.
cis-Diaquabis(2,2-bipyridyl)chromium(III) nitrate crystallizes in the mono-clinic system, space groupP21/c, witha=16.102(6),b=10.792(5),c=15.076(6) Å,=112.90(5)°, andZ=4. The saltlike structure was determined from X-ray crystallography and refined toR=7.5% for 3342 observed reflections. The Cr atom is octahedrally surrounded by twocis water molecules and by two chelated 2,2-bypiridyl ligands forming two nearly orthogonal planes. Selected bond distances are: Cr-O, 2.00(1) and 1.98(1) Å, Cr-N, 2.04 Å (mean).  相似文献   

8.
The title compound is monoclinic,M r =337.8,P21/c-C 2h 5 (No. 14),a=5.508(2),b=13.944(6),c=18.238(5) Å,=95.99(3)°,V=1393.1(9) Å3,Z=4,D x =1.61 g cm–3, (MoK)=0.71073 Å,F(000)=660.0,=10.3 cm–1, finalR=0.051 for 2122 observed [I>3(I)] reflections. The two six-membered rings resulting from the coordination of the 1,3-propanediamine ligands to the chromium atom are in the chair conformation. The Cr-N and Cr-F distances average 2.085(4) and 1.876(3) Å, respectively.  相似文献   

9.
Tris-(2,2,2)-triaminoethylamino-salicylidene iron(III) crystallizes in the monoclinic crystal system witha=7.766(2),b=25.423(5),c=13.318(5) Å, =118.04(3)°, space group P21/c,V=2320.8(6) Å3,Z=4, andD x=1.464 g cm–3. The center of the axially distorted octahedron is occupied by the Fe atom which is coordinated by six donor nitrogen and oxygen atoms infac positions. The planes of coordinated atoms (N and O) with the Fe(III) atom are almost planar and the maximum elevated atom from these planes is O(1) (–0.1065 Å).  相似文献   

10.
C38H35Cl2O2P2Re,M r=842, triclinic,P¯1,a=17.71(2),b=11.33(1),c=9.82(1) Å,=114.60(3),=90.84(3), =78.05(3),V=1747(2) Å3,D m(flotation)=1.60,D x=1.60 Mg m–3 forZ=2, MoK, =0.7107 Å,=41.6 cm–1,F(000)=836, room temperature. The structure was solved by standard methods from diffractometer data and refined to a conventionalR of 3.4% for 5412 observed reflections. The Re atom is six coordinate octahedral withtrans-Cl atoms andtrans-Ph3P groups. Relevant bond distances are: Re-P 2.533(1) and 2.535(1) Å, Re-O(ethoxo) 1.888(4) Å, and Re-O(oxide) 1.699(4) Å. The ethyl chain is partially disordered.  相似文献   

11.
MPN: C18H27N3O3,M r=333.43, monoclinic,P21/n. a=6.207(2),b=21.893(6),c=13.693(3) Å; =96.12(2)o,V=1850.1(8) Å3.,Z=4,D cal=1.20 mg/m3,F(000)=720, (CuK)=1.5418 Å, andT=298K.R=0.042 andwR=0.049 for 1675 observed reflections. MMN: C16H23N3O5,M r=337.38, triclinic,P,a=9.642(1) Å,b=10.123(5) Å,c=9.341(2) Å, =93.00(3)o, =90.96(1)o, =110.46(1)o, V=852.5(5) Å3,D cal=1.31 mg m–3.F(000)=360,Z=2, (CuK)=1.5418 Å,R=0.054 andwR=0.074 for 2804 observed reflections. The piperidine and morpholino rings assumechair conformation and orient each other at an angle of 44.8(1)o (MPN) and 47.1(1)o (MMN), respectively.Contribution No. 827 from DCB.  相似文献   

12.
The crystal and molecular structure of (C6H5)3SnOCOCCH2CH3 has been determined by a single crystal X-ray diffraction study. The crystal is monoclinic with space group P21/c,a=11.902(3),b=10.104(4),c=16.721(2) Å,=97.56(1)°,V=1930.4 Å3,Z=4 andD c =1.495 g/ cm3,F(0,0,0)=872,(CuK)=1.5418 Å. The structure was solved by the heavy-atom method and refined by full-matrix least-squares procedures to anR factor of 0.060 based on 2157 independent reflections. The results showed that the Sn-O bond distance is 2.064(4) Å. The average Sn-C bond distance is 2.126 Å. There is a weak coordination through the O of the CO group of the methacrylate residue (Sn-O(2) 2.774(5) Å) except for four normal coordinations. The coordination number at the Sn4+ is 5.  相似文献   

13.
C12H12N2O6 crystallized from methanol in the monoclinic space group P21/c (Z=4) witha=13.333(4),b=10.154(3),c=9.597(2) Å and=102.37(2)°.M r=280.24,V=1269.1(6) Å3,D x=1.466 g cm–3,(Mo K)=0.71069 Å,=1.29 cm–1,T=295 K. The structure was solved by direct methods and refined by full-matrix least-squares to a finalR (R w)=0.049 (0.057) for 916 observed reflections. The molecules are linked by strong N-HO(4) hydrogen bonds with NO distance of 2.995(4) Å. The infinite racemic chains run in [001] direction.  相似文献   

14.
The title mixed ligand complex was synthesized by the controlled oxidative displacement reaction of TeL 4 by iodine (L is diisopropyldithiocarbamate ion). Its crystals are monoclinic, space group P21 withZ=2 in a unit cell of dimensionsa=8.344(4),b=14.113(8),c=10.647(5) Å,=99.884(2)°, andV=1235.15 Å3, finalR=0.043 andR w =0.047 for 3553 unique reflections. The central tellurium atom shows a S4I2 six coordination with the two dithiocarbamate groups almost isobidentate, the average Te-S and the Te-I distances being 2.571(3) and 3.011(1) Å, respectively. The structure is monomeric in the solid state. No intermolecular short contacts are observed.  相似文献   

15.
The crystal structure of the title compound has been determined with three-dimensional MoK X-ray diffraction data. The space group and unit-cell parameters are:P21/c,a=8.610(3) Å,b=13.516(5) Å,c=16.818(5) Å,=94.95(3)° andV=1950.0(7) Å3. The structure was solved by direct methods, and refined by full-matrix least-squares techniques toR=0.0608 andR w=0.0648. The compound is a derivative of the popular-adrenolytic propranolol, and in the propanol part of the side chain shows the typicalgauche conformation.  相似文献   

16.
The crystal structure of oxacillin sulfone has been determined by single-crystal X-ray diffraction techniques and refined by full-matrix least squares. The penicillin molecule cocrystallizes with H2O in an orthorhombic space groupP212121 witha=10.303(7) Å,b=26.735(17) Å, andc=7.384(4) Å. The calculated density is 1.526 g cm–3, with aZ value of 4. FinalR-factor is 0.035. The oxidation of the sulfur atom is discussed in terms ofS1 conformation of the penam moiety and in terms of hydrogen-bond formation between one oxygen of the sulfur atom and the amidic hydrogen of the C6 side-chain. A comparison with oxacillin and cloxacillin sulfoxide is also made.  相似文献   

17.
The crystal structure of LiBr·(CH3OCH2CH2OCH3)2 has been determined from counter data and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupC2/c (C 2h 6 , No. 15) witha=13.518(4),b=8.007(3),c=12.252(4) Å,=98.08(2)°, andD calc=1.35 gcm–3 forZ=4. The finalR value for 489 observed reflections is 0.033. The lithium and bromine atoms lie on a crystallographic two-fold axis. The structure consists of discrete LiBr·(CH3OCH2CH2OCH3)2 units. The Li-Br separation is 2.57(1) Å. The two DME molecules are coordinated to the lithium atom through the four oxygen atoms at an average LiO separation of 2.09(3) Å.  相似文献   

18.
The X-ray crystal structure of the title compound, [Co(NCS)2(C6H6N4)2(H2O)2], has been determined. The crystals are monoclinic, space groupC2/c, with cell dimensionsa=15.6901(5),b=7.9248(10),c=16.1278(12) Å,=94.4(8)°V c=1999.44 Å3,M r=479.18,Z=4,D x=1.5918 Mg m3,Cu K radiation (graphite crystal monochromator, =1.54051 Å), (CuK)=39.08 cm–1,F(000)=980.00 andT=290 K. Final conventionalR-factor=0.051, andR w=0.053 for 1430 observed reflections and 141 variables. The structure was solved using the programsPatsys andDirdif. The Co atom is octahedrally coordinated (CoN2O2N2 chromophore), with only the 5-methyl-[1,2,4]-triazolo[1,5-a]pyrimidine (5mtp) ligands in thetrans positions. The triazolo pyrimidine rings are planar and coordinated through their N(3) atoms. The H2O ligands are also H-bond donors to N(4) (intramolecularly) and to the S atoms of the NSC anions (intermolecularly).  相似文献   

19.
The title compound crystallizes in the monoclinic space groupP21/a witha=13.092(2) Å,b=15.853(2) Å,c=15.406(3) Å,=103.00(1)°,V=3116(1) Å3, andD calc=1.237 g cm–3 forZ=4. The structure was solved by direct methods, and refined to a finalR value of 0.057. The phosphetane ligands adopt a nonlinear trans relationship. The four-membered rings are non-planar and have different flap angles of 6.1 and 20.3°. Virtual coupling is evident in the13C NMR spectrum of the title compound. Comparison of the13C NMR spectral data of this molecule with the parent phosphine ligand, the ligand oxide, and the mono-phosphine iron complex is provided.  相似文献   

20.
The crystalline product {[Se(CH3)3][(CH3)AlCl3]}n was prepared from reaction of SeCl4 with A1(CH3)3 in heptane. The organo-main group polymer crystallizes in the monoclinic space group P21/c with unit cell parametersa=11.218(3) Å,b=11.119(3) Å,c=9.915(2) Å,=107.82(2)°,V=1177.4(5) Å3, andD calcd=1.54 g cm–3 forZ=4. Least-squares refinement based on 1195 observed reflections I>3(I) in the range 3.50°<2<45.0° led to a finalR factor of 0.036 (R w=0.047). The asymmetric unit contains one selenonium ion, Se(CH3) 3 + , and one organoaluminum anionic species, (CH3)AlCl 3 . Secondary interactions (SeCl) serve to link the ions along two dimensions to form infinite layers. Thus, {[Se(CH3)3] [(CH3)A1C13]}n may be regarded as a layered organoaluminum-selenium polymer. The mean Se-C bond distance is 1.921(5) Å while the mean C-Se-C bond angle is 99.1(4)°. The independent Al-C bond distance is 1.927(8) Å while the mean Al-Cl bond distance is 2.166(7) Å.  相似文献   

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