Theoretical and Experimental Studies on the Metal Complex of Diethylenetriamino-trioxo-molybdenum(VI) [MoO_3(NH_2C_2H_4NHC_2H_4NH_2)]

1 INTRODUCTION Molybdenum is a biologically important trace ele- ment that occurs in the redox-active sites of moly- bdoenzymes involving in nitrogen, sulfur or carbon metabolism. The structural chemistry of molybde- num complexes has aroused considerable interest in view of its higher oxidation states to form a number of compounds containing MoO groups, and informa- tion on these is very useful in understanding the behavior of MO groups generally[1~3]. Molybdenum oxide-based solids hav…     

Solid and Solution Structural Studies of Dimeric and Tetrameric Molybdenum(Ⅵ) Malate Complexes

Reactions of potassium molybdate with racemic malic acid (H3mal = C4H6O5) result in the isolation of two mesomeric molybdenum malate complexes Ks[(MoO2)2O(R-mal)2][(MoO2)2O(S- mal)2]·4H2O 1 and (Him)2K6[(MoO2)4O3(R-mal)2][(MoO2)4O3(S-mal)2]·8H2O 2. Complex 1 belongs to the monoclinic system, space group C2/c with a = 14.8637(3), b = 6.9544(1), c = 19.6783(5) A, β = 100.081(2)°, V= 2002.70(7)A3, Mr = 1452.88, Z= 2, F(000) = 1416, T= 173 K, Dc = 2.409 g/cm3, μ(MoKa) = 2.167, R = 0.0283 and wR = 0.0733.2 is of triclinic system, space group P1 with a = 8.7707(2), b = 9.3310(3), c = 17.9093(7) A, α = 83.781(3), β = 85.626(2), γ= 84.822(2)°, V = 1447.84(8) A3, Mr = 2160.68, Z = 1, F(000) = 1048, T= 173 K, Dc = 2.478 g/cm3, μ(MoKα) = 2.230, R = 0.0234 and wR = 0.0584.1 is the first isolated dinuclear molybdenum(Ⅵ) malato complex in 1:1 molar ratio. The molybdenum atoms in the two complexes are six-coordinated in an approximately octahedral geometry. Two malates coordinate tridentately with the Mo atom via their α-alkoxy, α-carboxy and α-carboxy groups in 1 and 2. β-Carboxy group in 2 further links with the other two Mo atoms to give a tetrameric unit. The solution 1H and 13C NMR spectra indicate that dimeric malate molybdenum in 1 dissociates partly in solution and exists in an equilibrium with tetrameric species, while 2 is stable and retains its tetrameric structure without any dissociation.     

Studies on the Phenylfluorone-Mo(Ⅵ) Complex as Interacting Mode Spectroscopic Probe of Protein in OP Microemulsion Medium

The application of phenylfluorone (PF)-Mo(VI) complex as a spectroscopic probe is studied. In the presence of OP microemulsion at pH 3.04, PF-Mo(Ⅵ) complex combines protein rapidly to form a stable compound and the absorbance at 527 nm is in proportion to the concentration of protein in the range 0-16 μg mL-1 for bovine serum albumin (BSA). OP microemuslion media is introduced into protein determination, it has increased markedly the sensitivity of the system. The molar absorption coefficient was 5.98×l06 L mol-1 cm-1 for BSA. The assay, with sensitivity, simplicity and tolerance to many foreign substances, is applied to the determination of protein in samples with satisfactory results. Moreover, the binding number of BSA with the complex, which is determined by molar ratio and slope ratio methods, is in good agreement.     

Theoretical Studies on Reaction Mechanisms of HNCS with NH(X~3Σ)

IntroductionThe isothiocyanic acid(HNCS)is a sulfur analogof the well-known isocyanic acid HNCO[1,2].Becausethe latter species plays an important role in both atmos-pheric and combustion processes,it has attracted con-siderable attention[3—8].For example…     

Synthesis and Crystal Structure of a 1-D Chain Coordination Complex {[Mn2(HCAM)3(H2bipy)]·5H2O}n

The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n(H3CAM=4-hydroxypyridine-2,6-dicarboxylic acid,bipy=4,4′-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-dicarboxylic acid,4,4′-bipyridine and manganese carbonate under hydrothermal conditions,and its crystal structure was determined by X-ray diffraction method.The crystal belongs to the monoclinic system,space group P21/n with a=10.110(2),b=20.159(4),c=17.861(4) ,β=99.67(3)°,V=3.5884(12) nm3,Mr=901.47,Z=4,Dc=1.669 g·cm-3,μ=0.798 mm-1,F(000)=1840,the final R=0.0713 and wR=0.1853.The complex forms a 1-D chain bridged by HCAM,protonated 4,4-bipyridines link the 1-D chains to construct 2-D networks via N-H…O hydrogen bonds,and networks are further extended via π-π stacking and hydrogen bonds into 3-D supramolecular framework.     

Synthesis and Crystal Structure of a Two-dimensional Framework Supramolecular Complex [Mn(phen)(DPZDA)(H2O)]·2H2O

A novel two-dimensional supramolecular complex [Mn(phen)(DPZDA)(H2O)]·2H2Ohas been synthesized by the reaction of Mn(CH3COO)2, 1,10-phenanthroline (phen) and H2DPZDA (3,5-dimethyl-pyrazine-2,6-dicarboxylic acid). Elemental analysis, IR spectra and X-ray singlecrystal diffraction were carried out to determine the composition and crystal structure of the title complex. Crystal data: triclinic system, space group P-1, a = 7.7474(13), b = 9.3381(15), c =15.146(3)(A), α = 93.872(3), β = 102.451(11), γ = 105.261(11)°, C20H20MnN4O7, Mr = 483.34, Z = 2,F(000) = 498, V = 1023.2(3)(A)3, Dc = 1.569 g/cm3, μ = 0.697 mm-1, -9≤h≤9, -11 ≤k≤ 10, -18≤l≤12, R = 0.0365 and wR = 0.0901 for 3585 independent reflections (Rint = 0.0165) and 2923observed reflections (I ＞ 2σ(I)). Structural analysis indicates that Mn(Ⅱ) adopts a distorted octahedral geometry. The 2-D framework supramolecular structure of the title complex is constructed from hydrogen bonds and π…πinteractions.     

Syntheses and Structural Researches of Nine-Coordinated (NH4)[EuIII(Edta)(H2O)3] · H2O and (NH4)3[EuIII(Ttha)] · 5H2O1

The crystal and molecular structures of the (NH₄)[Eu^III(Edta)(H₂O)₃] · H₂O (I); Edta^4– is an ethylenediaminetetraacetate anion) and (NH₄)₃[Eu^III(Ttha)] · 5H₂O (II); Ttha^6– is a triethylenetetraminehexaacetate anion) complexes have been determined by single-crystal X-ray structure analysis. The crystal of complex I is orthorhombic with Fdd2 space group. The crystal data are as follows: a = 1.9505(8) nm, b = 3.5445(14) nm, c = 1.2442(5) nm, V = 8.602(6) nm³, Z = 16, M = 531.29, p = 1.579 g cm^–3, = 2.970 mm^–1, and F(OOO) = 3924. The final R and wR values are 0.0378 and 0.1030 for 2799 (I > 2.0(I)) unique reflections, and 0.0495 and 0.1072 for all 6237 reflections, respectively. The nine-coordinated [Eu^III(Edta)(H₂O)₃]^– complex anion has a pseudo-monocapped square antiprismatic structure in which the nine coordinated atoms, two N and four O are from one Edta ligand and three O atoms from water molecules. The crystal of complex II is monoclinic with P2₁/c space group. The crystal data are as follows: a = 1.0387(3) nm, b = 1.2737(4) nm, c = 2.3031(7) nm, = 90.870(5)°, V = 3.047(2) nm³, Z = 4, M = 784.58, C 51.83, H 4.32, N 115.12. = 1.710 g cm^–3, = 2.143 mm^–1 and F(000) = 1608. The final R and wR are 0.0400 and 0.0720 for 5909 (I > 2.0(I)) unique reflections, and 0.0747 and 0.0799 for all 13825 reflections, respectively. The nine-coordinated [Eu^III(Ttha)]^3– complex anion has a pseudo-monocapped square antiprismatic structure in which the Ttha acts as an ninedentate ligand with four N atoms of amino groups and five O atoms of carboxylic groups actually, in addition, there is a non-coordinated free carboxylic group in the structure.     

Theoretical and Experimental Studies on the Reaction Mechanism of Cl2 ＋ I2- 2ICl

1 INTRODUCTION The reactions between halogen and halogen are basic reactions in chemistry. Especially, in the syn- thesis of iodo-substituted aromatic hydrocarbon, the reaction Cl2 I2 = 2ICl could heighten the usage of iodine atom to 100%. So far, to the best of our know- ledge, the studies about halogen-halogen reaction mechanisms are very few. In detail, only the struc- ture and stability studies of X2Y- (X, Y = Cl, Br and I) ions by calculating reaction potential energy sur- face…     

Hydrothermal Synthesis, Crystal Structure and Fluorescent Property of a Novel Mo(Ⅴ) Phosphate [Zn(Mov6P4O31H10)2(C4H14N3)2]·2C4H13N3·8H2O

A new molybdenum phosphate [Zn(Mov6P4O31H10)2(C4H14N3)2]·2C4H13N3·8H2O 1 (C4H13N3 = diethylenetriamine) has been synthesized under hydrothermal condition. Single-crystal X-ray diffraction reveals that compound 1 crystallizes in the monoclinic, space group P21/n, a =13.1679(3), b = 22.1240(6), c = 13.6146(3) (A), β = 103.4847(7)°, V = 3856.95(16) (A)3,C16H90N12O70P8ZnMo12, Mr = 3035.41, Z = 2, Dc = 2.614 g/cm3, μ = 2.483 mm-1, F(000) = 2968, S = 1.014, the final R = 0.0196 and wR = 0.0506 for 7486 observed reflections (I ＞ 2σ(Ⅰ)). Compound 1 consists of two identical rings of six edge-sharing MoO6 octahedra interconnected by one ZnO6 octahedron, whereas the PO4 tetrahedra which share their apices with the MoO6 octahedra are only located on one side of each Mo6 ring. The 2-charge of polyanion [Zn(Mov6P4O31H10)2]2- unit is compensated in the crystal by two mono-protonated diethylenetriamines (C4H14N3)+. By hydrogen bonding interactions the polyanion of compound 1 is interconnected to form pseudo three dimensional molybdophosphate. Other characterizations by elemental analyses, IR spectrum and fluorescent spectrum are also described.     

Synthesis and Crystal Structure of Novel Dimer of Bismuth( Ⅲ ) Complex with Dithiotetrahydropyrrolocarbamate:[Bi (S2CNC4H8) 2 (NO3) ]2

A novel dimer of the bismuth ( Ⅲ ) complex with dithiotetrahydropyrroloearbamate, [Bi (S2CNC4H8)2 ·(NO3)]2, was synthesized and the crystal structure was determined by X-ray single crystal diffraction. The crystal belongs to a monoclinic system with space group P21/n, a=0. 64718(13) nm, b=2. 6738(6) nm, c=1. 0423(2) nm, β=106. 384(3)°, Z=4, V=1. 730(3) nm3, Dc=2.163 g/cm3, μ=10. 682 mm-1, F(000)=1072, R= 0. 0329, wR=0. 0659. The structure shows a distorted pentagonal bipyramidal configuration with the seven-coordinated central Bi atom. In the crystal, the molecular packing in the unit cell reveals that the two adjacent molecules are symmetrically linked each other in the dimer by virtue of a couple of Bi-S interaction.     

Experimental and Theoretical Studies on the Inclusion Complexation of β-Cyclodextrin with Phenothiazine Derivatives

Inclusion complexation of -cyclodextrin (-CD) with N-phenylphenothiazine ( 1), N-benzylphenothiazine ( 2) and N-phenethylphenothiazine ( 3) has been studied by means of UV-vis spectroscopy and molecular dynamics simulations. The association constants (K_a) were determined to be 126, 312 and 211 dm³/mol for inclusion of -CD with 1, 2 and 3, respectively. It shows that the K_a values are affected by the substituents of the guest compounds. The structures of the complexes and the conformation of the guest compounds bound by -CD in the complex have been discussed.     

Synthesis,Structure and Characterization of Three Metal Molybdate Hydrates: Fe(H2O)2(MoO4)2·H3O,NaCo2(MoO4)2(H3O2)and Mn2(MoO4)3·2H3O

Three metal molybdate hydrates,Fe(H2O)2(MoO4)2·H3O(FeMo),NaCo2(MoO4)2(H3O2)(CoMo)and Mn2(MoO4)3·2H3O(MnMo),were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray...     

Solvothermal Synthesis, Crystal Structure and Electrochemical Property of Complex [Co(p-MBA)2(2,2'-bipy)(H2O)]·(H2O)

One novel complex [Co(p-MBA)2(2,2'-bipy)(H2O)]·(H2O) has been synthesized by the reaction of p-methylbenzoic acid with 2,2'-bipyridine in the solvent mixture of water and methanol. It crystallizes in triclinic, space group P-1 with a=0.70479(14), b=1.1211(2), c=1.6718(3) nm, α=103.806(3), β=90.795(3), γ=104.207(3)°, V=1.2399(4) nm3, Mr=512.41, Dc=1.373 g/cm3, Z=2, F(000)=532, μ=0.733 mm-1, R=0.0432 and wR=0.0957. The crystal structural analysis shows that the cobalt atom is coordinated with three oxygen atoms from two p-methylbenzoic acids and one water molecule and two nitrogen atoms from one 2,2'-bipyridine,forming a distorted square-pyramidal coordination geometry. The cyclic voltammetry behavior of the complex is also reported.     

Synthesis and Crystal Structure of a New Praseodymium(Ⅲ)-Copper(Ⅱ) Polymeric Complex: [Pr2Cu3(L1)6]n (H2L1=NH{CH2COOH}2)

A novel polymeric Pr2Cu3 complex of iminodiacetic acid (H2L1=NH{CH2COOH}2) [Pr2Cu3(L1)6]n , 1, has been synthesized and structurally characterized. The title complex Pr2Cu3O24N6C24H30 (Mr=1258.97) crystallized in trigonal space group Pc1 (No. 165) with a = 13.424(4), c=14.752(6)(); V=2303(1)()3; F(000)=1226; λ(MoKα)=35.2 cm-1; Dc=1.820 g.cm-3; Z=2. The final R and Rw are 0.072 and 0.081 respectively for 1412 reflections with I>3σ(I). In crystal 1, the Pr3+ ion is nine-coordinated by 6 O atoms from three bidentate chelating carboxylate groups and 3 O atoms from three anti-anti bridging carboxylic groups of six L1 ligands; the Cu2+ ion is six-coordinated by 4 O and 2 N atoms from two pentadentate L1 ligands. Each pair of Pr(Ⅲ) atoms is bridged by three L1 ligands, each of which also chelates with one copper(Ⅱ) ion, thus forming a Pr2Cu3 cluster unit. Such cluster units are cross-linked by flexible L1 ligands into a three-dimensional coordination framework.     

Synthesis, Crystal Structure and Properties of Complex VO（C12H12N2O2） （C13H10NO2）

IntroductionAsthevanadate dependentenzyme ,ahaloperox idase,andvanadiumnitrogenasehavebeenfoundinsuccession ,somescientistsareinterestedinthecoor dinationchemistryandthebiochemistryofvanadi um[1] .Thereactivecenterofvanadiumbromoperoxi dasecontainstheoxovanadiumVO3+ coordinatedbyoxygenandnitrogenatoms[2 ] .However,thestudiesaboutoxovanadiumVO3+ coordinationcompoundscontainingbioactiveligandsarerarelyfound[3— 8] .Hydroximicacidthatcanbeconsideredtobethederivativeofthecarboxylicacid ,theamide…     

Synthesis and Crystal Structure of Copper(I) Chloride π-Complexes with N-Allyl- and N,N'-Diallylpiperazinium Dichlorides: [C3H5NH(CH2)4NH2]Cu2Cl4and [C3H5NH(CH2)4NHC3H5]0.5CuCl2

The crystals of copper(I) π-complexes with N-allyl piperazine derivatives, [C₃H₅NH(CH₂)₄NH₂]Cu₂Cl₄(I) and [C₃H₅NH(CH₂)₄NHC₃H₅]_0.5CuCl₂(II), were prepared by alternating-current electrochemical synthesis. X-ray diffraction study showed that compounds Iand IIcrystallize in the monoclinic system: for I, space group P2₁/a, a= 10.254(4) Å, b= 12.306(4) Å, c= 10.656(4) Å, γ = 98.83(3)°, V= 1329(2) ų, Z= 4, R= 0.0457 for 1334 independent reflections; for II, space group P2₁/n, a= 10.187(2) Å, b= 7.283(2) Å, c= 10.480(3) Å, γ = 100.72(2)°, V= 764.0(6) ų, Z= 4, R= 0.0371 for 1025 independent reflections. The structure of Iis composed of {Cu₂Cl₄(C₇H₁₆N₂)}₂dimers linked by fairly strong (N)H···Cl hydrogen bonds (2.35(4) Å). The structure of IIconsists of centrosymmetrical dimeric Cu₂Cl₄ ^2–anions, whose copper atoms coordinate the allyl groups of different centrosymmetrical organic cations. The dimer–ligand chains are stretched along the [ $ {11} $ 0] direction and are joined by hydrogen contacts (N)H···Cl (2.62(4) Å).     

Synthesis and Crystal Structure of a Copper(Ⅱ) Complex with a Tab-Tab Disulfide Ligand (Tab-Tab)[CuBr4] (Tab = Trimethylammoniumphenyl-4-thiolate)

Reaction of CuBr2 with TabHPF6/Et3N in methanol followed by dissolving the resulting precipitate in hydrobromic acid yielded purple blocks of the title complex [Tab-Tab][CuBr4] 1 (C18H26CuBr4N2S2). 1 crystallizes in the monoclinic system, space group P21/n with a = 9.686(3),b = 19.257(5), c = 13.399(4) (A), β= 93.610(9)°, V= 2494.2(13) (A)3, Z= 4, Dc = 1.911 g/cm3, T=193(2) K, Mr = 717.71, F(000) = 1396, μ = 74.58 cm-1, S = 1.126, R = 0.0748 and wR = 0.1736 for 2921 observed reflections with I ＞ 2σ(Ⅰ). The structure of 1 contains a discrete [CuBr4]2- dianion and a [Tab-Tab]2+ dication. In the dianion, the Cu atom is coordinated to four Br atoms forming a distorted tetrahedral coordination geometry. The bromides of the dianion interact with the H atoms of the phenyl and methyl groups of the dications to form a 1D hydrogen-bonded chain.     

Synthesis and Crystal Structure of a Nitronyl Nitroxide Complex {[Zn(NIT4Py)(fum)(H2O)2]·H2}n

The title compound {[Zn(NIT4Py)(fum)(H2O)2]·H2O}n, where N1T4Py=2-(4'-pyridinyl)-4,4,5,5-tetra-methylimidazoline-l-oxyl-3-oxide and rum=fumarate, has been prepared and structurally characterized by X-ray diffraction. It crystallizes in triclinic, space group P1 with a =6.9533(9), b=9.805(1), c=15.248(2)A, a=94.608(2), β=92.328(2),γ=105.840(2)°,C16H24N3O9Zn, Mr=467.75, V=994.8(2) A3, Z=2, Dc=1.562 g/cm3,μ(MoKa)=1.289 mm-1,F(000)=486, the final R=0.0243 and wR=0.0622 for 3505 independent reflections with Rint=0.0125. The Zn(Ⅱ) adopts a distorted five-coordinate triangle bipyramidal geometry. The basic framework structure of the complex is a 1-D chain. The intrachain hydrogen bonds are helpful to stabilize the 1-D chain structure. Furthermore, the chains are connected by O-H…O hydrogen bonds to give a 2-D double-layer network.