A New Pyridine-3,4-dicarboxylic Acid Bridged Zinc(Ⅱ) Coordination Complex: Crystal Structure,Quantum Chemistry and Luminescence Property

A new 2D metal coordination polymer, [Zn(pydc)(L)(H_2O)]_n·5nH_2O(1, H_2pydc = pyridine-3,4-dicarboxylic acid, L = 3-(2-pyridyl)pyrazole), was synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, powder XRD, FT-IR, thermogravimetric, fluorescence spectrum and elemental analysis techniques. Complex 1 belongs to the monoclinic system, P2_1/c space group, with a =10.707(5), b = 14.221(5), c = 13.278(5) ?, β = 102.071(5)°, V = 1977.1(14) ?~3 and Z = 2. It features a 2D network constructed by pydc~(2-) and L ligand. In addition, the quantum-chemical calculations were accomplished on ‘molecular fragments' extracted from the crystal structure of 1 using the PBE0/LANL2DZ method built in Gaussian 16 Program. The calculation values denoted the distinct covalent interaction between the coordinated atoms and Zn(Ⅱ) ion.     

Synthesis,Crystal Structure and Spectroscopy Studies on Complex cis-Os~Ⅱ(bpy)_2Cl_2 and Its Oxidation Product [cis-Os~Ⅲ(bpy)_2Cl_2](PF_6)

The treatment of(NH_4)_2 OsCl_6 with 2 equiv of bpy in ethylene glycol produced complex 1, cis-Os~Ⅱ(bpy)_2Cl_2(bpy = 2,2?-bipyridine). Its one-electron oxidation product 2, [cis-Os~Ⅲ-(bpy)_2Cl_2](PF_6), was obtained by the oxidation of 1 with(Cp)_2 FePF_6. Complex 1 crystallizes in the orthorhombic space group Pbca, and adopts distorted [MCl_2 N_4] octahedral coordination, in which four coordination sites are occupied by four nitrogen atoms from two bpy ligands and the other two sites are occupied by two chlorine atoms in a cis-position. Complex 2 crystallizes in monoclinic space group C2/c, and contains one [Os(bpy)_2Cl_2]~+ cation, one PF_6~- anion and two uncoordinated water solvent molecules.     

NUCLEAR MAGNETIC RESONANCE STUDIES OF THE INTERACTION OF Ca~(2+) WITH SIALIC ACID~*

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).     

Syntheses and Crystal Structures of the First Row Transition Metals with 1,6-Bis(2'-pyridyl)-2,5-dithiahexane

Six first row transition metal complexes with 1,6-bis(2′-pyridyl)-2,5-dithiahexane(Py_2S_2), namely, MnPy_2S_2Cl_2(1), FePy_2S_2Cl_2(2), Co Py_2S_2Cl(3), CoPy_2S_2(SCN)_2(4), NiPy_2S_2(SCN)_2(5) and NiPy_2S_2(N_3)_2(6), have been synthesized. A mixture of MCl_2·x H_2O(M = Mn, Co) in MeOH(FeCl_2·4H_2O in MeCN) and the stoichiometric amount of Py_2S_2 was stirred for 4 h at room temperature, then these aiming products 1, 2 and 3 could be obtained by purification. A mixture of MPy_2S_2Cl_2(M = Co, Ni) in MeOH and two equivalents of KSCN or NaN_3 was stirred for 4 h at room temperature. After that, complexes 4, 5 and 6 could be got by purifying. For 1, 2, 3, 4 and 5, the metal centers are hexa-coordinated in a similar distorted octahedral geometry and the crystal structures have the same space group Pbcn. The crystal structure of compound 6 belongs to monoclinic with space group P21/c. The coordinated atoms around M(Ⅱ) are two pyridyl N atoms(N(1) and N(2)), two thioether S atoms(S(1) and S(2)) and two chloride ions(Cl(1) and Cl(2)) in compounds 1, 2, and 3, but in 4, 5, and 6, two chloride ions(Cl(1) and Cl(2)) are replaced by another two N atoms from N_3~– or NCS~–.     

SYNTHESIS, MAGNETIC PROPERTY AND X-RAY CRYSTAL STUCTURE OF MIXED VALENT COBALT COMPLEX SALT [Co~Ⅲ Cl_2(py)_4][Co~Ⅱ Cl_3(py)]

Complex salt Co_2Cl_5(py)_5 (py=pyridine) was obtained by the reaction of CoCl_2·6H_2O with Bu_4NMnO_4 in pyridine in the presence of benzoic acid. It is monoclinic and crystallizes in space group P2_1/n, fw=690.64, a=28.652(5), b=14.108(4), c=7.424(3) ;β=90.09(1); V=3001(2)~3; Z=4, Dc=1.53g/cm~3. Final R factor is 0.041. The structure consists of a discrete cation [Co~ⅢCl_2(py)_4]~+ and an anion [Co~Ⅱ Cl_3(py)]~-. The Co~Ⅲ ion is coordinated by two Cl~- and four pyridine nitrogen atoms to form an octahedral geometry, and Co~Ⅱ is coordinated by three Cl~- and one pyridine nitrogen atom to form the apices of a tetrahedron. The variable-temperature magnetic susceptility measurement shows no magnet-exchange interaction between Co~Ⅲ and Co~Ⅱ ions.     

A NOVEL SYNTHETIC METHOD AND STRUCTURE OF TETRAKIS(BENZOATE)BIS(TRIPHENYLPHOSPHINE OXIDE)DICOPPER(II).OXIDATIVE ADDITION OF DIBENZOYL ON METALLIC COPPER

Dibenzoyl peroxide undergoes oxidative addition on metalliccopper with triphenylphosphine in a mixed solvent(acetone,dichloromethaneand trichloromethane),and affords the binuclear copper complex(Cu(C_6H_5COO)_2(OPPh_3))_2.Crystals are monoclinic,space group A_2/a,withcell parameters,a=24.337(3),b=10.566(1),c=21.579(2),β= 93.18(1)°,V=5540(1)~3,Z=4,R=0.042,and Rw=0.044 for 5872 observed reflections.Each copper ion is coordinated by four bridging benzoato ligands and onetriphenylphosphine oxide group to form binuclear complexes.     

STUDY ON SOME BIOLOGICALLY ACTIVE CO-ORDINATION COMPOUNDS OF METAL IONS (Ⅰ)——SYNTHESIS,CHARACTERIZATION,STRUCTURE AND ANTITUMOR ACTIVITY OF COMPLEX OF 3,6-DI-(DIMETHYLAMINO)-DIBENZOPY-RIODONIUM LANTHANUM EDTA

The title coordination compound has been synthesized by the reaction of HLaEDTA·7H_2Owith (CH_3)_2N-?-N(CH_3)_2·HCOO~- in ethanol aqueous solution. Thesingle crystal has grown from aqueous solution and has been characterized by IR, TG-DTA,X-ray powder diffraction, molar conductance, UV and ~1H-NMR. The determination of itscrystal and molecular structure shows that it crystallizes in space group P2_(1/n) with latticeparameters: a = 14.735A, b = 29.335A, c = 16.409A, β = 99.24°, v = 7009.30A~3, z = 4,F(000) = 3488, molecular weight M = 1756.90, D_C = 1.665g/cm~3. It has been refined by thefull matrix least squares method to final discrepancy factor R = 0.096. The anion [La2(EDTA)_2(H_2O)_4]~(2-) turns out to be a dimer, in which each of the twoEDTA~(4-) ions is coordinated to a La~(3+) ion with five of its six coordinating sites and the re-maining sixth one-the oxygen atom of carboxylis bridged to two La~(3+) ions, thus forming aparallelogrammic four-membered ring La_2O_2. The nine coordinations about     

A New Two-dimensional Cd(Ⅱ) Complex Assembled by 1,3,5-Benzenetricarboxylic Acid and 3-(2-Pyridyl)pyrazole

A new 2D coordination polymer, {[Cd_5(BTC)_2(L)_4(H_2O)_2]_n·2H_2O}_n(1, H_3BTC = 1,3,5-benzenetricarboxylic acid, HL = 3-(2-pyridyl)pyrazole) was synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, powder XRD, IR, TGA, fluorescence spectrum and elemental analysis techniques. Complex 1 belongs to the monoclinic system, P2_(1/c) space group, with a = 8.8732(4), b = 17.5179(7), c = 17.8123(7) ?, β = 103.1830(10)°, V = 2695.77(19) ?~3 and Z = 2. It features a 2D network constructed by BTC and L ligand. In addition, we analyzed Natural Bond Orbital(NBO) by using the PBE0/LANL2DZ method built in Gaussian 09 Program. The calculation results indicated obvious covalent interactions between the coordinated atoms and Cd(Ⅱ) ion.     

Two-dimensional correlation spectroscopic studies on coordination between carbonyl group of butanone and metalions

Two dimensional asynchronous spectra were used to characterize coordination between carbonyl group of butanone and metal ions by using an approach proposed in our recent paper.Spectral variation of n-π~*transition band of carbonyl group is used to probe the coordination even if metal ions does not possess any characteristic peak in spectra.Experimental results indicate that Ca~(2+) and Al~(3+) show considerable ability to coordinate with the carbonyl group of butanone and bring about spectral variation of the n-π~*transition band,which is manifested by cross peaks in 2D asynchronous spectra.     

From borophosphate to fluoroborophosphate: a rational design of fluorine-induced birefringence enhancement

The introduction of oxofluoride anion into anionic group assists to tune optical properties owing to the change of coordination,electronegativity,and according anionic framework.Here,we proposed a rational design of new compounds by fluorine-driven structure and optical property evolution.A new borophosphate Ba_2BP_3O_(11)with the monoclinic space group P2_1/c has been synthesized in the sealed system.Ba_2BP_3O_(11)exhibits a rare P–O–P bridge formation,which is the first example in alkaline-earth metal borophosphates.By further substituting[BO_4]~(3-)with[BO_3F]~(4-),the first alkaline-earth metal/lead fluoroborophosphates M_2BP_2O_8F (M=Ba and Pb) with the same space group were designed.Since the scissors effect of fluorine,in M_2BP_2O_8F (M=Ba and Pb),a BO_3F tetrahedron corner-sharing with three PO_4tetrahedra forms 1D chains along the b-axial direction,which are filled by MO_n(M=Ba/Pb,n=5,6,8) distorted polyhedra.The first principles calculation shows that the borophosphate Ba_2BP_3O_(11)has a birefringence about 0.013@1,064 nm,while the fluoroborophosphates M_2BP_2O_8F (M=Ba and Pb) have the values of 0.035 and 0.043@1,064 nm,respectively.Such an apparent enhancement in birefringence is derived from synergies of the oxyfluoride and cation.The introduction of fluorine-containing heteroanionic groups provides a feasible strategy to design novel promising optical materials.     

STUDIES ON RARE EARTH COMPLEXES OF QUARTERNARY AMMONIUM SALT——SYNTHESIS AND CRYSTAL STRUCTURE OF TETRAKIS-(TRIMETHYL-HEXADECYL AMMONIUM)DECANITRATO DINEODYMATE,((CH_3)_3C_(16)H_(33)N)_4Nd_2(NO_3)_(10)

A series of binuclear eleven-coordinated rare earth complexes with long chain quarternary ammonium salt have been synthesized. The general formula of the complexes may be represented by((CH_3)_3 C_(16)H_(33)N)_4Ln_2(NO_3)_(10) where Ln is La, Ce, Pr, Nd, Sm, Eu, Ga, Ho, Er or Y. The TG curve, the magnetic moment and the dissociation degree of the Nd complexes in alcoholic solution have been determined.((CH_3)_3C_(16)H_(33)N)_4 Nd,_2NO_3)_(10) was chosen as a representative of the complexes for the crystal structure determination. The crystal is monoclinic with space group P. Each Nd atom is coordinated by four terminal nitrate groups bidentately, and two Nd atoms are connected through two O atoms of the nitrate groups forming binuclear complex. Therefore, each Nd atom is surrounded by eleven oxygen atoms. The average bond length of the eleven Nd-O bond is 2.57, while the Nd-O bond length on the oxygen-bridge is 2.62.     

1D Lanthanide Coordination Polymers Based on 3-（Pyridin-4,yl）benzoic Acid： Syntheses, Structures and Luminescent Properties

Four novel 1D lanthanide coordination polymers with formula [Ln(3,4-pybz)3(H2O)2· H2O]n (Ln = 1 Sm; 2 Eu; 3 Tb; 4 Dy, 3,4-Hpybz = 3-(pyridin-4-yl)benzoic acid) have been synthesized by hydrothermal reactions of lanthanide oxide and 3-(pyridine-4-yl) benzoic acid. Single-crystal X-ray diffraction shows that the four compounds are isostructural. They all crystallize in a monoclinic system, space group P1. They have a doubly carboxylate-bridged infinite-chain structure with alternating Ln-(carboxylate)2-Ln linkages and one chelating carboxylate group on each metal center. The Ln ion also combines to two water molecules to form an eight-coordinate square antiprismatic geometry. The pyridine nitrogen atoms of the ligand do not coordinate to the metal centers but direct the formation of a 3D network through hydrogen bonding with coordinated water molecules. The photoluminescent properties of 2 and 3 have been also studied.     

Three 3D M~Ⅱ (M = Co,Ni, Zn) Supramolecular Polymers Constructed from O-vanillic Acid: Synthesis,Crystal Structure and TGA

The title compounds, [Co(H2O)6](OVA)2·2H2O 1, [Ni(H2O)6](OVA)2·2H2O 2 and [Zn(OVA)2·2H2O] 3 (HOVA = o-vanillic acid = 2-hydroxy-3-methoxybenzoate), were synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR and TGA. Compounds 1 and 2 are both of triclinic with space group P1. The metal atom coordinated by six water molecules displays a slightly distorted octahedral configuration. Interestingly, the carboxyl group from HOVA ligand does not coordinate to the metal atom. Correspondingly, compound 3 belongs to the monoclinic system, space group C2/c. Each zinc(Ⅱ) atom exhibits a distorted four-coordinated tetrahedral geometry. Two monodentate carboxyl groups link one zinc(Ⅱ) atom to form a mononuclear molecule. The structure feature is different from that of compounds 1 and 2, which could be attributed to the different coordinated numbers and radii of Co(Ⅱ), Ni(Ⅱ) and Zn(Ⅱ) atoms.     

Syntheses, Structures and Fluorescent Properties of Copper（II） and Manganese（II） Helical Complexes Bridged by 4,4＇-Dipyridylsulfide

Two isostructural helical coordination polymers, {[Cu(dps)2(Hssa)-(H2O)2]·3H2O}n (1) and {[Mn(dps)2(Hssa)(H2O)2]·2H2O}n (2), have been synthesized by the solvothermal reaction of dps and H3ssa with CuCl2 or Mn(CH3COO)2 (dps = 4,4'-dipyridylsulfide, H3ssa = 5-sulfosalicylic acid). Both compounds crystallize in monoclinic, space group P21/n. In either complex, the central metal ion (CuII for compound 1 and MnII for compound 2) is surrounded by one Hssa2ˉ ligand, two coordinated aquas and three dps molecules with a N3O3 donor set in a distorted octahedral coordination geometry. Half of the dps is monodentate and another half acts as μ2-bridging ligands. It is through the bridging function of dps that the neighbouring metal centers are connected and a one-dimensional helical structure of compound 1 or 2 forms. Fluorescence studies indicate that compounds 1 and 2 have blue emission bands centered at 403 and 405 nm, respectively.     

Synthesis, crystal structure and magnetic properties of a novel manganese(II)-nitronyl nitroxide-azido(μ_(1,1) and μ_(1,3)) one-dimensional complex

A novel one-dimensional manganese(Ⅱ) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2((μ1.1-N3)(μ1,3-N3) . EtOH]n was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(Ⅱ) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in trans axial position. Mn(Ⅱ) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through u1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds,π-π interactions and hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic interactions between the radical and Mn(Ⅱ) ion, weak antiferromagnetic inter     

Solvothermal Synthesis,Crystal Structure and Characterization of a New Binuclear Nickel(Ⅱ)Complex with 2-(4-Methylbenzoyl)benzoic Acid

A new binuclear nickel(Ⅱ) complex[Ni_2(MBBA)_2(HPT)_2(H_2O)_2]·2H_2O (1) was synthesized with nickel hydroxide,2-(4-methylbenzoyl)benzoic acid (HMBBA) and 3-(pyridin-2-yl)-1H-1,2,4-triazole (HPT).It crystallizes in the monoclinic space group P2_1/n with a=14.5902(13),b=8.8191(6),c=17.6120(14)?,β=110.830(9)o,V=2118.0(3)?~3,M_r=958.26,D_c=1.503 g/cm~3,Z=2,μ(Mo Ka)=0.959,F(000)=992,the final GOOF=1.001,R=0.0353 and w R=0.09864.Each central Ni(II) ion is coordinated by two oxygen and three nitrogen atoms,forming a distorted square pyramidal geometry.The XRD,TG,spectrum analysis and magnetic properties of 1 were studied.     

Structures and Photoluminescent Properties of 3D Ho(Ⅲ) and Y(Ⅲ) Complexes with 2,4,6-Pyridinetricarboxylate

Two 3D rare earth coordination polymers {[Ho(ptc)(H_2O)_(2.5)]·0.5 H_2O}n(1) and {[Y2(ptc)2(H_2O)_5]·H_2O}n(2)(H_3ptc = 2,4,6-pyridinetricarboxylic acid) have been synthesized with Ho(Ⅲ) or Y(Ⅲ) chloride and H_3ptc by hydrothermal method. The X-ray structure analyses display the two complexes are isomorphic and crystallize in monoclinic crystal system with P21/n space group for 1 and P21/c space group for 2. Ho(Ⅲ) and Y(Ⅲ) both show two different coordination modes. One is nine-coordinated and forms a distorted tricapped trigonal prism and the other is eight-coordinated to get a distorted bicapped trigonal prism. The ptc3-also shows two different coordination modes by connecting four or three rare earth ions. The photoluminescent properties of 2 show that it can emit blue fluorescence at 440 nm with excitation at 335 nm. The fluorescence lifetime of 2 is 1.64 μs and the absolute fluorescence quantum yield is 10.2%.     

A New Mn(Ⅱ) Complex Assembled by 2,5-Dihydroxy-1,4-benzenedicarboxylic Acid and 2,2'-Bipyridine: Synthesis,Structure and Theoretical Calculation

A new complex [Mn(DHTA)(bipy)_(0.5)]n(1, H_2 HTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, bipy = 2,2'-bipyridine) was hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, single-crystal and power X-ray diffraction. It belongs to monoclinic system, C2/c space group with a = 12.874(13), b = 11.302(12), c = 17.352(18) ?, β = 101.574(15)°, V = 2474(4) ?3 and Z = 4. It displays a one-dimensional zigzag chain-like structure, which was further extended into a three-dimensional supramolecular structure by hydrogen bonds and π-π interactions. Moreover, we analyzed Natural Bond Orbital(NBO) of 1 in using the PBE0/LANL2 DZ method built in Gaussian 03 Program. The calculation results show the obvious covalent interaction between the coordinated atoms and Mn(Ⅱ) ion.     

CRYSTAL STRUCTURE INVESTIGATION OF VANADYL COMPLEXES OF TRIDENTATE LIGAND (Ⅰ)——THE CRYSTAL STRUCTURES OF BIS[(1-(2,4-PENTANE- DIONATO(NITROBENZOYL) HYDRAZONE)-2- ETHOXY)OXOVANADIUM] AND BIS-[(1-(2, 4-PENTANEDIONATO-(3-NITROBENZOYL) HYDRAZONE)-2- METHO

The title complexes were obtained by the reactions of bis(2,4-pentanedionato)oxovanadium VO(Acac)_2 and m-nitrophenylhydrazide m-NO_2PhCONHNH_2 in the media EtOH and MeOH respectively. The compound (Ⅰ) crystallizes in the space group PT with unit cell dimensions a=8.123(2), b=10.409(5), c=10.822(4), α=65.78(3)°, β=85.50(3)°,γ=89.04(3)°. The compound (Ⅱ) crystallizes in the space group P2_1/a with unit cell dimensions a=7.745(2), b=19.164(5), c=10.787(4), β=107.87(2)°. The resuhs of structural analyses show that the two compounds have the same characteristics: the tridentate ligand formed by condensation occupies three of the four equatorial positions of vanadium and the rest equatorial position is occupied by alkoxy group RO~-. As RO~-group also bridges the sixth coordinated position of each vanadium atom, it brings about the formation of the new type binuclear complexes of vanadium.     

Synthesis,Crystal Structure and Magnetic Properties of the New Quaternary Thiophosphate Rb_2FeP_2S_6

A new quaternary thiophosphate Rb_2FeP_2S_6 was synthesized by the alkali metal halide flux method.The compound crystallizes in the monoclinic space group P2_1/c(No.14) with a = 6.042(3),b = 12.338(6),c = 9.045(4) ?,b = 124.25(2)°,V = 557.3(5) ?~3 and Z = 2.Its structure features 1-D infinite _∞~1[FeP_2S_6]~(2-) chains and counter cations Rb~+.It shows a band gap of 2.03 eV.The nearest intra-chain Fe~(2+) cations are antiferromagnetically coupled with each other,and there are weak ferromagnetic-like interactions between neighboring _∞~1[FeP_2S_6]~(2-) chains,resulting in two successive magnetic phase transitions.