Temperature-dependent Syntheses of Two Manganese(Ⅱ) Coordination Compounds Based on an Ether-bridged Tetracarbolylic Acid

0D dinuclear manganese(Ⅱ) coordination compound and 1 D chain manganese(Ⅱ) coordination polymer, namely [Mn_2(μ-L)(phen)4]·4 H_2 O(1) and {[Mn_2(μ5-L)(phen)_2]·H_2O}n(2), have been constructed hydrothermally using H4 L(H4 L = 2,3,3',4'-diphenyl ether tetracarboxylic acid), phen(phen = 1,10-phenanthroline), and manganese chloride at 120 and 160℃, respectively. The products were isolated as stable crystalline solids and were characterized by IR spectra, elemental analyses, thermogravimetric analyses(TGA), and single-crystal X-ray diffraction analyses. Single-crystal X-ray diffraction analyses revealed that two compounds crystallize in the triclinic or monoclinic system, space group P1 or P2_1/c. Compound 1 discloses a discrete dimeric structure, which is assembled into a 3 D supramolecular framework through O–H···O hydrogen bond. Compound 2 has a chain structure. Structural differences between compounds 1 and 2 are attributed to the different reaction temperature. Magnetic studies for compound 2 demonstrate an antiferromagnetic coupling between the adjacent Mn(Ⅱ) centers.     

Syntheses,Crystal Structures and Magnetic Properties of Two New Low-dimensional Manganese (Ⅱ) Coordination Compounds

Two new low-dimensional Mn(Ⅱ) coordination compounds of Mn(H_2pimdc)_2(phen)(compound 1) and [Mn(Hpimdc)(phen)]n·nH_2O(compound 2) were synthesized, where H_3pimdc is a 2-propyl-imidazole-4,5-dicarboxylic acid and phen is 1,10-phenanthroline. Both compounds were thoroughly analyzed by X-ray single-crystal diffraction, element analysis, IR spectra, PXRD and thermal analysis. X-ray single-crystal diffraction analyses indicate that the phen ligands terminate metal ions on two sides to prevent the linkage between the neighboring metal ions into a higher dimensional structure in compounds 1 and 2. Compound 1 is constructed from mononuclear molecules which form the 1D helical supramolecular chain by N–H···O hydrogen bonds. In compound 2, Hpimdc is a tetradentate bridging ligand, which binds Mn(Ⅱ) ions to generate a single-stranded right helical chain parallel to the b axis. These 1D chains are additionally coupled by H-bonds as well as π···π stacking interactions, which formed a 3D supramolecular structure. Additionally, compound 2 demonstrated temperature-dependent magnetic susceptibility and negative value of θ(equal to –9.09 K), which is indicative of weak antiferromagnetic interactions between Mn(Ⅱ) ions.     

Structural Diversity and Photoluminescent Properties of Two Mn(Ⅱ) Sulfoterephthalate Complexes from Multi-pyridine N-containing Ligands

Solvothermal reaction of manganese(II) salt with monosodium 2-sulfoterephthalate(2-NaH_2stp) and two multi-pyridine N-containing auxiliary ligands results in the formation of two new complexes formulated with [Mn_2(Hstp)_2(bpp)_2(H_2O)_4](1) and [Mn_3(stp)_2(tpy)_3(H_2O)](H_2O)_5(2)(bpp = benz-2,3-pyrimidine-[2,3-f]-1,10-phenanthroline, tpy = 2,2?:6?,2??-terpyridine). X-ray diffraction structural analyses of two complexes reveal their structural diversity(0D and 1D) due to the difference of auxiliary ligands. 1 is a discrete structure, in which the Mn(Ⅱ) ion is hexa-coordinated with one stp, one bpp ligand and two water molecules. Complex 2 is a one-dimensional(1D) chain-like structure with three crystallographically independent Mn(Ⅱ) ions. The photoluminescent properties could be assigned to the π-π* transition of 2-sulfoterephthalate ligands.     

Synthesis,Structure and Slow Magnetization Relaxation of Co(Ⅱ) Complexes from a Flexible Imidazole-based Ligand

The employment of a flexible imidazole-based ligand(H_2L), condensed from 1 Himidazole-2-carbaldehyde and 1,2-bis(aminooxy)ethane, and Co~(2+) salt has led to the formation of Co(Ⅱ) complexes [Co(H_2L)_2Cl]Cl·4CH_3OH(1) and [Co(H_2L)(NCS)_2]_2·2C_4H_(10)O(2), in the presence of different anions, i.e, Cl-and SCN-, respectively. Single-crystal X-ray analyses show that complex 1 with a square pyramid(C_(4v)) local environment exhibits a two-dimensional(2D)layered(4,4)-net framework and complex 2 displays a dinuclear molecule box with a T_d local environment. By comparison between complexes 1 and 2, the versatile configuration of ligand including cis-and trans-form isomer has a significant effect on the structures of the resulting complexes. The magnetic properties of 1 and 2 are also investigated. The ac magnetic susceptibility revealed that 2 exhibits the characteristic of slow magnetization relaxation.     

Four Complexes of Mn(Ⅱ), Co(Ⅱ), Ni(Ⅱ) and Cu(Ⅱ) Based on 2-Morpholine-4-yl-4,6-di-pyrazol-1-yl-1,3,5-triazine

Three azide bridged complexes, namely, [Mn_2L_2(N_3)_4(H_2O)_2](1), [Co_2L_2(N_3)_4]·(H_2O)_3(2) and [Ni_2L_2(N_3)_3(H_2O)]N_3·(H_2O)_4(3)(L = 2-morpholine-4-yl-4,6-di-pyrazol-1-yl-1,3,5-triazine), were synthesized by the reaction of L ligand, sodium azide with Mn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) chlorides. The copper(Ⅱ) chloride combined with thiocyanate and L ligand to form a mononuclear complex [CuL(CH_3OH)(SCN)(NCS)](4). Complexes 1~4 were characterized by IR, elemental analysis and X-ray crystallographic analysis. It was worth noting that two Mn(Ⅱ) atoms were connected by the end-to-end mode in 1, while Co(Ⅱ) and Ni(Ⅱ) atoms were connected by the end-on mode in 2 and 3. In complex 4, the central copper atom was coordinated with a sulfur atom and a nitrogen atom of the two thiocyanate ligands, respectively. Hydrogen bonds, π-π stacking interactions, thermogravimetric analysis and fluorescence properties of 1~4 were studied.     

Magnetic Properties in Mononuclear Gadolinium(Ⅲ) and Terbium(Ⅲ) Complexes Based on Ethoxylphenylsubstituted Nitronyl Nitroxide Radical and Hexafluoroacetylacetonate Ligand

Two new lanthanide complexes with ethoxybenzene-substituted nitronyl nitroxide radical(NIT-C_8H_9O) and hexafluoroacetylacetonate(hfac) ligand,[Gd(NIT-C_8H_9O)_2(hfac)_3]·C_7H_(16)(1) and [Tb(NIT-C_8H_9O)_2(hfac)_3]·C_7H_(16)(2),have been successfully synthesized and characterized by IR spectroscopy,elemental analyses,thermogravimetry analyses,and single-crystal X-ray diffraction.Both 1 and 2 exhibit a mononuclear structure in which the nitronyl nitroxide radical and hfac ligand act as monodentate and bidentate chelating modes,respectively.Magnetic studies show that ferromagnetic interactions(between intramolecular Gd and radical) and antiferromagnetic interactions(between the intramolecular radicals) coexist in complex 1.No obvious frequency dependent out-of-phase signals were observed in complex 2.     

Cu(Ⅰ) and Cu (Ⅱ) helical complexes formed with oligobipyridine ligand

A new asymmetric oligobipyridine ligand, 1-(5'-methyl-2, 2'-bipyridin-5-yl)-2-(6'-methyl-2, 2'-bipyridin-6-yl)ethane (L), in which the bipyridine units are bridged by CH_2CH_2 at 5, 6'-position has been synthesized. The ligand L reacts with Cu(Ⅰ) and Cu(Ⅱ) ions giving double-stranded helical complexes [Cu_2~ⅠL_2] (ClO_4)_2·Et_2O (1) and [Cu_2~ⅡL_2 (OH) (H_2O)][ClO_4]_3(2), respectively. Complexes 1 and 2 were characterized by X-ray diffraction analyses, ES-MS, ESR and cyclic voltammetry, etc. Differing from the oligobipyridine ligands bridged by CH_2CH_2 at 6,6'-or 5,5'-position, the ligand L not only forms a double-stranded helicate with Cu(Ⅰ) ion, but also gives a double-stranded helicate with Cu(Ⅱ) ion. The results show that the linkage mode of the spacer group to the bipyridine units exerts a great impact on the formation of helix.     

Layered and three-dimensional uranyl–organic assemblies with 4,4′-oxidiphthalic acid

Hydrothermal reactions of uranyl nitrate and 4,4'-oxidiphthalic acid(H_4L) resulted in the formation of three new uranyl-organic framework materials,namely(NH_4)_2[(UO_2)_3(L)_2]·5H_2O(1),(NEt_4)[(UO_2)_3(H_2O)(L)(HL)](2) and(UO_2)_7(H_2O)_2(phen)_4(L)_2(HL)_2(3)(NEt_4 = tetraethylammonium,phen = 1,10-phenanthroline).These three structures all comprise common uranyl pentagonal bipyramids.In 1,UO_7polyhedra are linked by hexadentate ligands to form a 3D framework with 1D channels,in which are located NH_4~+ ions and water molecules.While in 2,the organic ligands adopt pentadentate and hexadentate coordination modes,ligating UO_7 units to create a layered structure with channels filled by NEt_4~+ ions.For 3,uranyl square bipyramids are also accommodated together with pentagonal bipyramids,which are linked by tetradentate carboxylate ligands to produce the layered assembly.Phen molecules also coordinate to the uranyl centers to build up the structure.Luminescent studies indicate that 2 and 3 exhibit the characteristic uranyl emission.     

Synthesis,Crystal Structure and Fluorescent Properties of Silver and Cadmium Complexes

Two new complexes [Ag(bix)]n·n NAA·n H_2O(1) and [Cd(NAA)(phen)_2(H_2O)]2· 2CH_3COO-·H_2O(2)(bix = 1,4-bis(imidazol-1-ylmethyl)benzene,HNAA = α-naphthylacetic acid,phen = 1,10-phenanthroline) have been successfully synthesized under hydrothermal conditions.Their structures have been determined by elemental analyses,IR spectroscopy,TG and single-crystal X-ray diffraction analysis.The intermolecular hydrogen bonding or π-π stacking interactions extend the complexes into a 3D supramolecular structure.Moreover,the luminescent properties of complex 2 have been investigated in the solid state.     

A series of novel Zn(Ⅱ) and Mn(Ⅱ) metal-organic frameworks constructed by 2,4-bis-oxyacetate-benzoic acid: syntheses,structures and photoluminescence

A new carboxylic acid ligand, 2,4-bis-oxyacetate-benzoic acid(H3BOABA), was designed and introduced to construct novel metal-organic framework materials. [Zn Na(BOABA)(phen)(H2O)]·H2O(1), Zn Na(BOABA)(2), Mn3(BOABA)2(phen)2(3), [Mn2(BOABA)(OH)]·(H2O)2(4)(CCDC: 885138, 885137, 894225, 883094) were hydrothermally synthesized and characterized by elemental analysis, IR spectra and thermal gravimetric analyses. Crystal structures of the complexes were determined by single crystal X-ray diffraction method. Complex 1 is a one dimensional double edges non-interpenetrated framework decorated by the phen ligands on the surface. Complex 2 is an unique three dimensional open framework, consisting of Zn(II) and Na(I). Complex 3 is an unique double edges one dimensional MOF containing a [Mn3(BOABA)2(phen)2]n non-interpenetrated structure. Complex 4 is a two dimensional plane structure containing two Mn atoms in the same coordination environment. The interaction between four complexes and DNA were studied by Et Br fluorescence probe. Meanwhile, photoluminescence studies revealed that these four complexes display strong fluorescent emission bands in the solid state at room temperature.     

Two New Copper(Ⅱ) Complexes with p-Cyanobenzoic Acid: Synthesis,Crystal Structures and Properties

The complexes of [Cu(bpy)(H2O)(CBA)2]n 1 and [Cu(phen)(H2O)(CBA)2]·H2O 2 based on p-cyanobenzoic acid(HCBA) have been synthesized in aqueous ethanolic solution at room temperature. The single-crystal X-ray diffraction studies demonstrated that complex 1 crystallizes in orthorhombic and complex 2 is of triclinic system. The results indicate the complex 1 shows a 1D chain structure bridged by two carboxylic oxygen atoms from CBA–, and complex 2 is a mononuclear structure. Through intermolecular hydrogen bonding and π...π stacking interactions, the complexes are assembled into supramolecular structures. Complex 1 has been characterized by magnetic measurements. The magnetic measurement indicates that weak ferromagnetic interaction(zJ= 0.038(5)) between the Cu2+ ions is dominant in the structure. The IR spectrum and results of thermal and elemental analyses are also presented.     

Two Co(Ⅱ) Complexes Constructed from 1-(3,5-Dicarboxybenzyl)-3,5-pyrazole Dicarboxylic Acid:Syntheses,Structures and Magnetic Properties

Two new complexes[Co_2(L)(4,4′-bip)(H_2O)_3]_n (1) and{[Co(L′)_2(phen)]·2H_2O)}_n (2)(H_4L=1-(3,5-dicarboxybenzyl)-3,5-pyrazole dicarboxylic acid,H_3L′=1-(3,5-dicarboxybenzyl)-3-pyrazole carboxylic acid,4,4′-bip=4,4′-bis(1-imidazolyl)biphenyl,phen=1,10-phenanthroline) were synthesized.Complexes 1 and 2have been characterized by IR spectrography,X-ray single-crystal diffraction,elemental analysis and thermogravimetry.1 crystallizes in monoclinic system,space group P2_1/c.Complex 2 crystallizes in monoclinic system,space group I2/a.It is remarkable that in situ hydrothermal decarboxylation was observed during preparing complex 2.In addition,magnetic analysis indicates that antiferromagnetic interaction exists among Co(Ⅱ) ions in complexes 1 and 2.     

A Copper(Ⅱ) Complex Based on N-(4-hydroxybenzyl)-L-serine:Synthesis,Crystal Structure and Inhibitory Activity on PTP1B and TCPTP

A novel copper(Ⅱ) complex with the reduced Schiff base, [Cu(L)_2]·H_2O(I, HL = N-(4-hydroxybenzyl)-L-serine), was prepared in aqueous solution and characterized by elemental analysis, FT-IR, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a = 8.9040(18), b = 9.1530(18), c = 24.891(5) ?, V = 2028.6(7) ?3, Z = 4, C_(20)H_(26) Cu N_2O_9, Mr = 501.97, Dc = 1.644g·cm3, μ = 1.135 mm-1, F(000) = 1044, GOOF = 1.194, the final R = 0.0484 and w R = 0.1420 for 6186 observed reflections(I 2σ(I)). In I, two L- anions are coordinated to the copper ion in tridentate and bidentate chelating modes, respectively, resulting in the coordinated geometry of copper ion to be a distorted square pyramid. The intermolecular hydrogen bonds between the complexes, complexes and lattice water molecules lead to a 2D supramolecular network. The bioactivity of the complex as a potential PTPs inhibitory agent in vitro was investigated, displaying potent inhibition against PTP1B(IC50, 0.27 μM) and TCPTP(IC50, 0.57 μM) with a moderate selectivity.     

Cyanide-bridged One-dimensional Heterobimetallic Complex cis-[Fe~Ⅱ(phen)_2(CN)_2Mn~Ⅲ(salen)](PF_6): Synthesis,Crystal Structure and Magnetic Properties

Dicyanide building block cis-Fe(phen)_2(CN)_2 and [Mn~Ⅲ(salen)](ClO_4) have been used to design and synthesize a cyanide-bridged complex, resulting in a heterobimetallic one-dimensional(1D) zigzag chain complex 1, [cis-Fe(phen)_2(CN)_2Mn(salen)](PF_6)(phen =1,10-phenanthroline, salen=N,N?-ethylenebis-(salicylideneaminato) dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in the monoclinic P2_(1/c) space group and the asymmetric unit contains one [-NC-Fe(phen)_2(μ-CN)-Mn~Ⅲ-(salen)-]~+ cation and one PF_6~- anion. In the cationic structure of 1, each Fe~Ⅱ(phen)_2(CN)_2 connects two [Mn~Ⅲ(salen)]~+ with two cyanide groups in a cis-conformation, and in turn each [Mn~Ⅲ(salen)]~+ unit links two Fe~Ⅱ(phen)2(CN)_2 building blocks in a trans-conformation, resulting in a 1D [-NC-Fe~Ⅱ-CN-Mn~Ⅲ-]n chain. Furthermore, the electronic absorption spectra and electrochemical and magnetic properties of complex 1 have also been studied.     

Synthesis,Crystal Structure,and Luminescence of a 1D Chain Cd(Ⅱ) Polymerwith 3,3?,5,5?-Benzene-1,3-biyl-tetrabenzoic Acid

A new Cd(Ⅱ) coordination polymer, [Cd(H_2btb)(bpy)]_n(1, H_4btb = 3,3?,5,5?-benzene-1,3-biyl-tetrabenzoic acid, bpy = 2,2?-bipyridine), has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric(TG) analyses and single-crystal X-ray diffraction techniques. Complex 1 belongs to monoclinic system, C2/c space group. In 1, two carboxylate groups of the H_4btb ligand adopt bidentate chelating and μ_2-η~1:η~1 coordination modes, respectively, bridging the Cd(Ⅱ) atoms to generate a 1D polymeric ribbon. In addition, the photoluminescence property of complex 1 has also been studied.     

A Double Azole-bridged Dinuclear Copper(Ⅱ) Complex Containing 4-Pyridyl-NH-1,2,3-triazoles: Synthesis,Structure and Magnetism

A new dinuclear copper(Ⅱ) compound [Cu_2(CH_3COO)_2(L)_2(H_2O)_2]·4H_2O(1, HL = 4-pyridyl-NH-1,2,3-triazole) has been synthesized and characterized. Single-crystal X-ray diffraction showed that complex 1 crystallizes in monoclinic space group P2_1/c with a = 0.8427(1), b = 1.0981(1), c = 1.3610(1) nm, β = 93.364(4)°, V = 1.2573(1) nm~3, M_r = 643.56, Z = 2, D_c = 1.700 g/cm~3, μ = 1.760 mm~(-1), R = 0.0376, wR = 0.0981, and possesses a planar Cu_2N_4 six-membered ring, in which both Cu(Ⅱ) ions are bridged by two 1,2,3-triazole ligands. The neighboring dinuclear molecules are bound by strong intermolecular hydrogen bonds to create 1-D chains expanding along the b axis, which further form a 3-D supramolecular framework. Magnetic susceptibility measurement indicated the presence of weak antiferromagnetic interactions within the complex. The best fit using spin Hamiltonian yields the magnetic coupling constant J = –14.82 cm~(-1) above 30 K. The magnetic data are compared to those obtained for related double diazine bridged dinuclear copper(Ⅱ) complexes and magnetostructural correlations are discussed.     

A 3D Nickel(Ⅱ) Complex Constructed by Bis(2-dimethylaminoethyl) Ether: Solvothermal Synthesis,Crystal Structure and Catalytic Properties

Treatment of bis(2-dimethylaminoethyl) ether(BDMAE) with nickel acetate afforded a novel 3D nickel(Ⅱ) complex [Ni(BDMAE)(H_2O)_3·(CH_3COO)_2·(H_2O)_2] under solvothermal conditions. Its crystal structure was characterized by elemental analysis, IR spectrum, PXRD and single-crystal X-ray diffraction analysis. The complex belongs to the orthorhombic system, space group C2221 with a=8.823(2), b=13.932(3), c=17.563(4) ?, V=2158.9(8) ?~3, Z=4, C_(12)H_(36)N_2NiO_(10), Mr=427.14, Dc=1.314 g/cm~3, F(000)=920 and μ=0.944 mm~(-1). Single-crystal X-ray diffraction reveals that the mononuclear nickel(Ⅱ) ion is six-coordinated to one oxygen, two nitrogen atoms of the BDMAE ligand and three oxygen atoms of coordinated water molecules. The complex exhibits a 3D supramolecular structure through a variety of intermolecular and intramolecular hydrogen bonding interactions. In addition, the complex has been investigated for catalytic properties towards the Henry reaction of nitromethane with p-nitrobenzaldehyde, and the results indicated that the 1-p-nitrophenyl-2-nitroethanol product was obtained in excellent yield under optimum conditions with the complex as the catalyst.     

Synthesis,Structure and Luminescence Property of a New Two-dimensional Znic(Ⅱ) Coordination Polymer

Based on 5-dimethylamino-isophthalic acid(H_2dia) and 1,2-bis(4-pyridyl)ethylene(bpe) mixed linkers, a new d~(10)-configuration Zn(Ⅱ) coordination polymer material, [Zn(dia)(bpe)(H_2O)]n(1), was synthesized. In the asymmetric unit, there are one Zn~(2+) ion, two dia~(2-)anions, one neutral bpe linker and one free H_2O molecule. In the complex, adjacent Zn~(2+) ions are alternately bridged by the dia~(2-)dianions to generate chains which are further connected by flexible bpe ligands to form a two-dimensional(2 D) layer structure. In topology, the structure of 1 represents a non-interpenetrating 4-connected sql topology. Moreover, infrared spectroscopy, elemental analyses, thermogravimetric analysis, powder X-ray diffraction, solid UV-Vis absorption spectra and photoluminescent property of 1 are also investigated.     

Syntheses,Crystal Structures and Antibacterial Activities of Schiff Base of Nickel(Ⅱ) and Copper(Ⅱ) Complexes

A new kind of Schiff base HL(HL= 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-Leucine methyl ester) and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2(L′ = 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-leucine) have been synthesized and structurally determined by X-ray diffraction. For HL: crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1: the Ni(Ⅱ) ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2: the Cu(Ⅱ) ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.     

Four New Cu（Ⅱ） Complexes with Benzotriazole-based Ligands： Syntheses,Crystal Structures and Theoretical Investigations

Four new Cu（Ⅱ） complexes with two benzotriazole-based ligands, [Cu2（L^1）2（NO3）2]· 2H2O （1）, [Cu2（L^1）2]·2ClO4·2H2O （2）, [Cu2（HL^2）2（NO3）4]·2CH3COCH3 （3） and [Cu（HL^2）2（Cl）]·Cl·2CH2Cl2 （4）, where HL^1 = 1,3-bis（benzotriazol-2-yl）-2-propanol and HL^2 = 1,3-bis（benzotriazol-1-yl）-2-propanol, were synthesized and structurally characterized by elemental analyses, IR and single-crystal X-ray diffraction analyses. It is revealed that complexes 1～3 have dinuclear structures, while 4 possesses a one-dimensional （1-D） chain structure, which extends in two orthogonal orientations. In 1～4, the coordination numbers of Cu（Ⅱ） centers range from four to six, which may be attributed to the different geometries and coordination abilities of the ligands and anions. The L^1 ligand in complexes 1 and 2 adopts a tridentate di-chelating coordination mode, whereas ligand HL^2 in complexes 3 and 4 has a bidentate bridging coordination mode. The different coordination modes of these two ligands may be explained by the different charges of nitrogen donor atoms in the benzotriazole ring, which has been investigated by density functional theory （DFT） calculations.