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1.
<正> Preliminary information. The vanadyl complexes are found to be increasingly used in the areas of catalysis, new materials research as well as in bio chemistry. Therefore, more attentions have been paid to such compounds. The title complex K_2[VO(C_2H_3O-3)_2(C_2H_2O_3)] H_2O has been prepared by reaction of VOSO_4 with hydroxyacetic acid in aqueous solution, with KOH added to a suitable PH value.  相似文献   

2.
Nine complexes(RC_5H_4)_2Ti(O_2CC_6H_4X)_2(R=H,CH_3;X=H,o-Cl,o-OH,o-NH_2,o-NHPh)have been conveniently prepared by the reaction of(RC_5H_4)_2TiCl_2 with 2 equiv.sodium salts of corresponding carboxylic acidin aqueous solution containing acetylacetone.The carboxylate ligands inthe complexes coordinate to titanium atom in monodentate mode.  相似文献   

3.
IR and NMR spectra of novel bionics insecticide—C_5NS_4O_6H_(12)Na·H_2O have been studied. The molecular and crystal structures of the compound also have been determined. The compound crystallizes in the monoclinic space group C_(2h)~5, - P2_1/n with α= 8.0972. (9) , b =16.262(4), c = 10.370(3), β= 94.26(2)° and z = 4.The result shows that N atom in this compound captures a proton to form HN~ group, Na~ is in statistical disorder. Therefore, the structural formula of tho compound is (CH_3)_2HN~ —CH(CH_2S_2O_3~-)_2·1/2 (Na~ )_2·H_2O.  相似文献   

4.
The complexes of demethylcantharic acid coordinating with Zn~(2+), Cu~(2+), Ni~(2+) and Co~(2+) wereprepared and the five crystal structures were all determined by X-ray diffraction. Metal ions in thefive structures are of six-membered coordination. The demethylcantharate ions can act as a tri-,tetra- or penta-dentate ligand toward metal ions to form ion-pair structure, chain structure or threedimensional polymer structure respectively. The bridge oxygen atom in ligand always participatesin coordination. In the structures of KM(C_8H_8O_5)_2·6H_2O, the formal valence of M (Ni, Co) is+3, but the data of crystal structures show that M are M~(2+) ions and Ni may form a Ni~(2+) -stabilizedligand radical. In addition, the metal ions are assumed to be probes and some possible Interactionsbetween the acceptor and the receptor are discussed.  相似文献   

5.
The title compound has been prepared by reaction of VOSO_4 with hydroxyacetic acid in aqueous solution, adding KOH to a suitable pH value. The crystals are monoclinic, space group P2_1/b with cell parameters: α=10.075(2), b=9.857(3), c=14.314(3), γ=115.29(2)°, Z=4. Intensities of 1714 independent reflexions having I≥3σ(I) were collected on a CAD4 diffractometer with MoKα radiation. The structure was solved by Patterson and direct methods and refined by full matrix least-squares method to R=0.060. In the complex the ratio of centric V atom to hydroxyacetate ligands is M:L=1:3, two hydroxyacetate ligands are chelated to V atom in a cis arrangement, the other is monodentate ligand with a carboxyl O atom to grasp the cation VO~(2+).  相似文献   

6.
Separation of trivalent lanthanides(Ln(Ⅲ)) and actinides(An(Ⅲ)) is a key issue in the advanced spent nuclear fuel reprocessing. In the well-known trivalent actinide lanthanide separation by phosphorus reagent extraction from aqueous komplexes(TALSPEAK) process, the organophosphorus ligand HDEHP(di-(2-ethylhexyl) phosphoric acid) has been used as an efficient reagent for the partitioning of Ln(Ⅲ) from An(Ⅲ) with the combination of a holdback reagent in aqueous lactate buffer solution. In this work, the structural and electronic properties of Eu~(3+) and Am~(3+) complexes with HDEHP in nitric acid solution have been systematically explored by using scalar-relativistic density functional theory(DFT). It was found that HDEHP can coordinate with M(Ⅲ)(M=Eu, Am) cations in the form of hydrogen-bonded dimers HL_2~-(L=DEHP), and the metal ions prefer to coordinate with the phosphoryl oxygen atom of the ligand. For all the extraction complexes, the metal-ligand bonds are mainly ionic in nature. Although Eu(Ⅲ) complexes have higher interaction energies, the HL_2~- dimer shows comparable affinity for Eu(Ⅲ) and Am(Ⅲ) according to thermodynamic analysis, which may be attributed to the higher stabilities of Eu(Ⅲ) nonahydrate. It is expected that this work could provide insightful information on the complexation of An(Ⅲ) and Ln(Ⅲ) with HDEHP at the molecular level.  相似文献   

7.
Two copper (Ⅱ) a-methacrylate complexes with benzimidazole, Cu [CH_2=C( CH_3)-COO]_2(C_7H_6N_2)_2(1) and Cu_2 [CH_2=C(CH_3)-COO]_4(C_7H_6N_2)_2 (2), have been prepared and characterized by elemental analyses, IR and electronic reflectance spectroscopies. The single crystal X-ray diffraction study of the two complexes shows that complex 1 has a square planar configuration, while complex 2 has a binuclear cage structure. The crystal structural analyses show that both complexes 1 and 2 are monoclinic, with space group P2_1/c, a=0.924 16(8) nm, b=1.233 02(13) nm, c =0.989 1(3) nm, β=91.912(13)°, D_c=1.386 g/cm~3, Z=2, R=0.033 9 for the former; and a=0.905 7(2) nm, b=2.252 1(5) nm, c=1.623 5(4) nm, β=90.11(2)°, D_c =1.411 g/cm~3 , Z=4, R=0.056 8, Cu-Cu=0.266 21 nm for the latter. Different structural types of complexes 1 and 2 were produced simultaneously in the reaction of copper (Ⅱ) α-methacrylate with benzimidazole in methanol solution. The forming mechanism of the complexes has been summarized.  相似文献   

8.
The title compound crystallizes in the space group C_i~1-Pī with cell constants a=9.589, b=10.486, c=11.139, α=103.27° β=98.20° and γ=103.16°. After deriving the position parameters of all V atoms by Patterson method, the coordiuates of all the non-hydrogen and hydrogen atoms were obtained from successive Fourier and difference syntheses, and the leastsquares refinement for all atoms gave a final discrepancy factor R=0.0279. The chemical content within a unit cell has been identified definitely as (Na~+)_2·(H_2V_(10)O_(28)~(4-))·2((CH_2)_6N_3N-H~+)·8H_2O.  相似文献   

9.
A new coordination compound of cis-bis(1,10-phenanthroline)glycinecobalt(Ⅲ)chloridate tetrahydrate,cis-[Co(phen)_2gly]Cl_2.4H_2O,has been prepared by glycinereacted with cis-[Co(phen)_2Cl_2]Cl,then isolated by SP-Sephadex C-25 H~+ form column.The crystal and molecular structure of the new compound has been determined by RIGAKUAFC5R four circle diffractometer,5032 independent reflections were collected ofwhich 3781 observable reflections were used for structure refinement.The crystal ismonoclinic,space group C2/c,with a=35.13(1),b=9.637(3),c=17.485(6),β=115.08(Z)~,V=5362(3),Z=8.The structure was refined by full matrix least-squaresprocedure to a final R=0.041 and R_=0.060.The molecular formula was CoC_(28)H_(28)N_5O_8Cl_2.with molecular weight M_r=636.38,D_c=1.58g/cm~3,μ=8.88cm~(-1)and F_((000))=2624.  相似文献   

10.
The coordination compounds,{Cu[CH_3C_6H_4N(CH_2COO)_2]}.2H_2O and{Cu[CH_3OC_6H_4N(CH_2COO)_2]}.2H_2O,have been prepared and its crystal struc-tures determined.The final discrepancy factors are R=0.052,R_w=0.061 for(I)and R=0.052,R_w=0.039 for(Ⅱ).The geometry of the coordination poly-hedron with Cu(Ⅱ)is a distorted tetragonal pyramid for(Ⅰ)and an unsym-metrical and extended tetragonal bipyramid for(Ⅱ),respectively.The re-sults of EHMO calculations indicate that the ligand mainly provided thefield with very few of its electrons being coordinated to the central atom.  相似文献   

11.
The title compound has been synthesized by the reaction of sodium α-dithionaphthoatewith CuCl_2 in an alkaline aqueous solution or by the reaction of α-dithionaphthoic acid withCuCl_2 in an organic solvent, The crude product was recrystallized in a mixture of CS_2 andC_2H_5OH. The crystals obtained are red and stable in air. The structure of the title compound is determined by a single-crystal X-ray diffractionanalysis. The crystal belongs to monoclinic space group C_(2h)~5- P(2_1/a) with unit cell parameters:a= 16.453(3)A, b=12.651(4)A, c=23.182(7)A, β=100.5(2)°, V=4744.6A~3,Z=4. Thestructure was refined to R=0.06 for 4707 reflections. In the molecule, Cu_4 cluster has a distorted tetrahedral configuration. Surrounding thistetrahydron are four α-perthionaphthoate ligands, coordinated to copper through the sulfuratoms. One of the sulfur atoms in each ligand forms sulfur bridge with copper atoms,while the other is coordinated to only one copper. The three Cu--S bonds formed by thethree sulfur atoms with a given copper atom are approximately coplanar. Each group--C--S_2 with Cu atom on a vertex of the tetetrahedron forms a five-member ring. Thesefive-member rings are also approximately cooplanar. The molecule possesses an approachingS_4 point symmetry. The mechanism for the formation of the title compound involves a redox reaction.which is discussed in this paper.  相似文献   

12.
The reaction of the reduced Schiff base HL(N-(4-hydroxybenzyl)-L-serine) with Zn(CH_3COO)_2·2H_2O in aqueous solution afforded [Zn(L)_2]·3H_2O(I). The complex has been characterized by elemental analysis, FT-IR, powder X-ray diffraction, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a=9.197(2), b=10.445(2), c=24.149(5) ?, V=2319.8(8) ?~3, Z=4, C_(20)H_(30)N_2O11 Zn, M_r=539.83, Dc=1.546 g·cm~3, μ=1.122 mm~(-1), F(000)=1128, GOOF=0.971, the final R=0.0206 and w R=0.0506 for 4346 observed reflections(I 2σ(I)). In complex I, each Zn(II) ion coordinates with three carboxyl oxygen atoms and two amine nitrogen atoms from three L-anions, forming a distorted five-coordinated trigonal bipyramidal geometry. Complex I exhibits a 1D wavy chain structure that is extended by hydrogen-bonding interactions to form a supramolecular network. The bioactivity of the complex as a potential PTPs inhibitor in vitro was investigated, displaying potent inhibition against PTP1B(IC_(50), 0.24 μM) and TCPTP(IC_(50), 0.53 μM) with a moderate selectivity.  相似文献   

13.
Ring-opening polymerization of ε-caprolactone (CL) catalyzed bylanthanocenes, O(C_2H_4C_5H_3CH_3)_2YCl (Cat-YCl) and Me_2Si[(CH_3)_3SiC_5H_3]_2NdCl(Cat-NdCl) has been carried out for the first time. It has been found that both yttroceneand neodymocene are very efficient to catalyze the polymerization of CL, giving high molec-ular weight poly (ε-caprolactone) (PCL ). The effects of [cat] / [ε- CL] molar ratio, polymeriza-tion temperature and time, as well as solvents were investigated and polymerization tem-perature is found to be the most important factor affecting the polymerization. The bulkpolymerization gives higher molecular weight PCL and higher conversion than that in solu-tion polymerization. NaBPh_4 was found to promote the polymerization of ε-caprolactone,and thus to increase both the polymerization conversion and MW of poly (ε- caprolactone ).  相似文献   

14.
The two crystal structures of C_(17)H_(17),N_2O_2Cl_2PS (NP-8) and C_(17)H_(19)N_2O_2PS (NP-10-Ⅱ) have beendetermined by Patterson method. The crystals belong to monoclinic system with space group of P2_1/aand P2_1/n respectively. There are four molecules in the unit cell. Cell parameters: a = 26.622 (7)A, b = 7.711 (2) A., c = 9.461 (3) A, β = 94.90°(4) and a = 18.879(3) A, b = 10.199 (13) A, c = 8.948(3) A, β= 94.30°(3) for the two cells. After refinement by block diagonal matrix least squares me-thod, R factors are 0.046 for 2971 reflections of NP-8 and 0.076 for 1711 reflections of NP-10-Ⅱ. Referring to molecular structures of NP-8 and NP-10-Ⅱ spectra data have been satisfactorilycxplained. The characteristic features of the structures have been discussed.  相似文献   

15.
Praelolide is a new compound which was isolated out from the gorgonian, Menella praelonga (Ridley), collected from the South Sea of China at Zhanjiang, Guangdong. The molecular formula is C_(28) H_(35) O_(12)C1. The research result by X-ray diffraction method on the crystal structure is presented. The compound is orthorhombic with space group P2_12_12, cell dimensions α=16.936, b=16.709, c=10.333, and Z=4. The structure has been solved by direct method and refined to R=0.055 for 2257 unique observable reflexions by least-squares. The molecule is composed of the major conformational isomer in which the three main rings(a six-membered ring, an eight-membered ring, a six-membered ring) take separately the form of chair-chairboat-chair, a five-membered actone ring, a C1 substitution, 4 acetate groups, and a three-membered epoxide ring. The absolute configuration of the molecule has also been determined by statistics (R factor ratio =1.012) and Bijvoet pairs observation. For 30 pairs of the greatest anomalo  相似文献   

16.
The interaction of Ca~(2+) with sialic acid has been investigated by 500 MHz proton nuclear magnetic resonance spectroscopy. The changes of chemical shifts were observed for all sialic acid protons at different Ca~(2+) concentrations, and these spectral observations were also accompanied by changes in the J-coupling constants between the H_7 and H_8 protons and between the H_8 and H'_9 potens. Analysis of these Ca~(2+)-induced changes indicated that three oxygen atoms among (OH)_7, (OH)_8 and (OH)_9 of sialie acid formed a geometrical space suitable for Ca~(2+) coordination As a consequence, sialic acid provided a high-affinity binding site for Ca~(2+), the binding constant was about 104.72m~(-1).  相似文献   

17.
A new coordination polymer,{[Ag_2(bpp)_2(H_2O)_2]·bpdc·3H_2O}_n,derived from the ligand biphenyl-4,4'-dicarboxylic acid(H_2bpdc),has been obtained through a hydrothermal technique(bpp = l,3-bis(4-pyridyl)propane).Its single-crystal structure has been characterized by single-crystal X-ray diffraction,powder XRD,FT-IR,TGA and elemental analysis techniques.The single-crystal X-ray diffraction reveals that complex 1 consists of 1D infinite[Ag(bpp)(H_2O)]_n~(n+)cationic chains,2D anionic layer constructed by bpdc anions and free water which provide charge compensation in the crystal structure.The 1D infinite[Ag(bpp)(H_2O)]_n~(n+) cationic chains and 2D anionic layer are further stacked in-ABAB- fashion through intermolecular H-bonding to form a 3D sandwich-like framework.In addition,the luminescent property of complex 1 in the solid state at room temperature was investigated.  相似文献   

18.
The title complex [Cu(CH_3COO)_2(C_4H_7NO)]_2 has been synthesized and its structure hasbeen determined by X-ray diffraction method.The compound crystallizes in the triclinic spacegroup P .The cell dimensions are:a=0.7775(4),b=0.8229(3),c=0.8913(5)nm,a=101.85(4)°,β=110.36(4)°,v=90.61(3)°,z=1.The struture has been refined to a R valueof 0.089.The two copper atoms are bridged by four acetate groups.Pyrrolidinone cooridinates tocopper at the apical site through its oxygen atom.  相似文献   

19.
The title complex [ErY(Gly)_6(H_2O)_4](ClO_4)_6 5H_2O has been synthesized.Its crystalstructure has been determined by X-ray diffraction method.The crystal is triclinic with space groupP1.The unit cell parameters are as follows:a=11.518(4),b=14.105(7),c=15.530(6) ,α=96.61(3),β=102.74(3),γ=105.70(3)°,V=2327.7(17) ~3,Z=2,Dc=2.091g/cm~3.The structure has been refinedto a final R of 0.0785.The crystal is an infinite chain complex,in which four carboxyl groups fromglycine molecules bridge the Er(Ⅲ)and Y(Ⅲ)ion,other two carboxyl groups bridge two adjacentEr(Ⅲ)or two Y(Ⅲ)ions.  相似文献   

20.
This paper reports the crystal and molecular structure of title compound. 3978 three-dimensional independent reflections were collected by Syntex R3 four circle diffractometer. The crystal is monoclinic with space group P2_1, a=8.074(1), b=11.309(4), c=27.793(9), β=106.84°(2), Z=4. The molecular formula is Pt(C_8 H_(15)O_4N)_a Cl_2. The crystal structure was solved by Patterson method and refined by block matrix least squares refinement techniques. The final R factor is 0.039.The result of crystal structure analysis shows that Pt(Ⅱ) has a dsp~2 hybrid orbital and square coordination. Two C1 atoms are located oppositely to two diethyi-dichloride-di-L-aspartare. N atoms have sp~3 tetrahedral hybrid configurations and form the coordinate bonds with Pt(Ⅱ) atom using their lone pair electrons. By reason of molecular packing and due to the formation of inner hydrogen bonds in the complex molecule, the configuration of L-aspartic acid in the title complex is more twisted than that of L-and DL-aspartic acid  相似文献   

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