One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characte...One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characterized by elemental analysis(EA), IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. The crystal of 1 crystallizes in monoclinic, space group P21/n with a = 12.2860(5), b = 13.8246(6), c = 19.0140(8) A, β = 104.3870(1)°, V = 3128.2(2) A3, Z = 4, C32H28N7 Ni O8, Mr = 697.32, Dc = 1.481 g/cm^3, F(000) = 1444 and μ(Mo Kα) = 0.684 mm-1. The final R = 0.0704 and w R = 0.1764 for 5485 observed reflections with I 2σ(I) and R = 0.1087 and wR = 0.2010 for all data. Topology analysis reveals that complex 1 is a 3D 2-fold interpenetrated {4^4·6^6}-nov net based on the 1D [Ni(OTP)]n chain and the 2D [Ni2(bib)3]n sql sheet. And the variable-temperature magnetic susceptibility measurements exhibit weak antiferromagnetic coupling interaction.展开更多
The geometrical structures of 2 (2 hydroxyphenyl) pyridine(PP) and its protonation states were optimized by means of the B3LYP/6 31G(d) method. For all the selected systems, the existence of H bond is in favor of ...The geometrical structures of 2 (2 hydroxyphenyl) pyridine(PP) and its protonation states were optimized by means of the B3LYP/6 31G(d) method. For all the selected systems, the existence of H bond is in favor of the stability of the systems. On the basis of the optimized geometrical structures, their electronic spectrum properties were studied by time dependent density functional theory(TD DFT) methosd via a hybrid function of B3LYP and 6 31G(d) basis set. The TD DFT calculation result predicts the absorption spectrum of PP at 324 nm(3.82 eV), which is in very good agreement with the experimental value of 322 nm( 3.85 eV ) determined in solvent chloroform. The absorption spectra of the two protonation states both exert a red shift in various pH media.展开更多
The employment of N-hydroxy-pyridine-2-carboxamidine in the coordination chemistry of zinc(II), nickel(II) and manganese(II) under solvothermal conditions is reported. Four complexes of compositions, [Zn2(O2CMe...The employment of N-hydroxy-pyridine-2-carboxamidine in the coordination chemistry of zinc(II), nickel(II) and manganese(II) under solvothermal conditions is reported. Four complexes of compositions, [Zn2(O2CMe)3{(py)C(NH2)NOH}4](OH) (1), [Zn4(OH)2{(py)C(NH2)- NO}4CI2]'3MeCN (2), [Ni(SO4)(H20){(py)C(NH2)NOH}2]'H2O (3) and [Mn(SO4){(py)C(NH2)- NOH}2]n (4), have been synthesized by rationally choosing different metal salts and dexterously employing acetate and sulfate ions as the bridging groups. Luminescent properties for 2 suggested strong emission in the solid state at room temperature. Variable temperature (2.0-300 K) magnetic studies for the linear chain complex 4 indicate weak antiferromagnetic Mn(Ⅱ)...Mn(Ⅱ) exchange interactions.展开更多
In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the c...In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the combined use of KHIs and some synergists, which would enhance KHIs’ inhibitory effect on both hydrate nucleation and hydrate crystal growth. In this study, a novel kind of KHI copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s (HGs) is used in conjunction with TBAB to show its high performance on hydrate inhibition. The performance of HGs with different monomer ratios in structure II tetrahydrofuran (THF) hydrate is investigated using kinetic hydrate inhibitor evaluation apparatus by step-cooling method and isothermal cooling method. With the combined gas hydrate inhibitor at the concentration of 1.0 wt%, the induction time of 19 wt% THF solution could be prolonged to 8.5 h at a high subcooling of 6℃. Finally, the mechanism of HGs inhibiting the formation of gas hydrate is proposed.展开更多
Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxa...Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxalic acid (H2ox) afford three novel supramolecular polymers (CPs), namely, {[M2(ox)(L)2][bdc][M2(Hox)2(OH)(H2O)4]·3H2O}n (M = Mn for 1, Co for 2, Cd for 3). Single-crystal X-ray diffraction analysis reveals that complexes 1-3 are isostructural and the 3D supramolecular structure was connected through non-covalent interactions. With the help of H2ox, the L ligands cheated with center atoms forming a butterfly [M2(ox)(L)2]2+ building block. The bdc2- ligand linked with the unprecedented [M2(Hox)2(OH)2(H2O)4] units through strong O-H...O hydrogen bonds forming a zigzag chain, which are further connected through π-π interactions between L and bdc2- ligands to form a 3D supramolecular structure. Moreover, elemental analyses, IR, thermogravimetric, PXRD and luminescence have been investigated.展开更多
The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence o...The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence of Na OH, and its structure was determined by X-ray diffraction analysis. The crystal is of triclinic system, space group P1 with a = 6.8264(6), b = 7.5890(4), c = 13.0960(7) A, α = 93.447(4), β = 98.772(6), γ = 92.615(6)o, V = 668.26(8) A3, Z = 2, the final R = 0.035 and wR = 0.09 for 2259 observed reflections with I 〉 2σ(I). The preliminary biological test showed that the title compound has activities against Stemphylium lycopersici(Enjoji) Yamamoto, Fusarium oxysporum. sp. cucumebrium, and Botrytis cinerea with inhibitory to be 51.19%, 62.02% and 15.56%, respectively.展开更多
A new trinuclear nickel complex,[Ni3(pdc)3(2,2'-bipy)3(H2O)2]·2H2O(H2pdc = pyridine 2,6-dicarboxylic acid,2,2'-bipy = 2,2'-bipyridine) has been hydrothermally synthesized and characterized by IR,elemen...A new trinuclear nickel complex,[Ni3(pdc)3(2,2'-bipy)3(H2O)2]·2H2O(H2pdc = pyridine 2,6-dicarboxylic acid,2,2'-bipy = 2,2'-bipyridine) has been hydrothermally synthesized and characterized by IR,elemental analysis and X-ray diffraction methods.Crystal data for this complex:monoclinic,space group P21/n,a = 21.206(4),b = 10.002(2),c = 28.066(6),β = 108.18(3)°,C51H41N9Ni3O16,Mr = 1212.06,V = 5.656(2) nm3,Dc = 1.423 g·cm-3,μ(MoKα) = 1.062 mm-1,Z = 4,F(000) = 2488,GOOF = 1.034,the final R = 0.0543 and wR = 0.1237 for 6149 observed reflections with Ⅰ 〉 2σ(Ⅰ).In the complex,three nickel(Ⅱ) ions are bridged by the pyridine 2,6-dicarboxylic acid groups,and all nickel(Ⅱ) ions are seven-coordinated by nitrogen atoms of 2,2'-bipyridine and pyridine 2,6-dicarboxylic acid and oxygen atoms from pyridine 2,6-dicarboxylic and water to adopt a severely distorted pentagonal bipyramidal geometry.The emission and excitation peaks of the complex in ethanol solutions are located at 336 and 316 nm,respectively.展开更多
A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ...A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.展开更多
A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At ...A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.展开更多
A three-dimensional coordination polymer [Mn2(μ1.3-N3)4(μ-PP)2]n (PP = 3-(pyrazin-2-yloxy)-pyridine) has been synthesized with 3-(pyrazin-2-yloxy)-pyridine and azide anion as mixed bridge ligand, and its c...A three-dimensional coordination polymer [Mn2(μ1.3-N3)4(μ-PP)2]n (PP = 3-(pyrazin-2-yloxy)-pyridine) has been synthesized with 3-(pyrazin-2-yloxy)-pyridine and azide anion as mixed bridge ligand, and its crystal structure was determined by X-ray crystallography. The crystal data: triclinic system, space group P1, with a = 6.794(4), b = 9.885(6), c = 9.947(6) A, α = 64.170(6), β= 84.190(8), γ= 85.319(8)°, V = 597.7(6)A^3, Z = 1, C18H14Mn2N18O2, Mr = 624.35, Dc = 1.735 g/cm^3, F(000) = 314 and μ = 1.117 mm^-1. In the crystal, the azide anion acts as a bridge ligand and makes adjacent Mn(Ⅱ) ions connect into a two-dimensional sheet on the ab plane, then 3-(pyrazin-2-yloxy)-pyridine serves as a bidentate bridge ligand to connect neighboring sheets along展开更多
Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and...Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion.展开更多
The title compound, [Ni(C8N3H7)3]4[Mo8O26]2·6H2O 1, has been synthesized from the reaction of 2-(1H-pyrazol-3-yl)-pyridine (L) with (NH4)2MoO4·2H2O and NiCl2·6H2O. Elemental analysis, IR, UV spe...The title compound, [Ni(C8N3H7)3]4[Mo8O26]2·6H2O 1, has been synthesized from the reaction of 2-(1H-pyrazol-3-yl)-pyridine (L) with (NH4)2MoO4·2H2O and NiCl2·6H2O. Elemental analysis, IR, UV spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the compound. Crystal data: C96H96Mo16N36Ni4O58, Mr = 4451.97, monoclinic system, space group P21/n, a = 20.846(5), b = 14.825(5), c = 23.122(5) A ,β= 91.594(5)°, V = 7143(3)A^3, Z = 2, F(000) = 4344, Dc = 2.070 g/cm^3,μ = 1.968 mm^-1, R = 0.0452 and wR = 0.1056 for 17102 independent reflections (Rint = 0.0442) and 11074 observed reflections (I 〉 2σ(I)). Structural analysis indicates that two kinds of octamolybdates ([α-Mo8026]^4- and [β-Mo8026]^4-) co-exist in the compound. This is the first example of a supramolecular structure containing L complex as well as both α- and β-octamolybdate clusters.展开更多
The title compound [Cu2(m-NO2)(aepy)4](ClO4)3 (Cu2C28H40N9Cl3O14, Mr = 960.12, aepy = 2-(2-aminoethyl)pyridine) was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in ...The title compound [Cu2(m-NO2)(aepy)4](ClO4)3 (Cu2C28H40N9Cl3O14, Mr = 960.12, aepy = 2-(2-aminoethyl)pyridine) was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group C2/c with cell parameters: a = 21.958(3), b = 12.205(2), c = 15.180(3) ? b = 106.06(1), V = 3909.5(12) ?, Z = 4, Dc = 1.631 g/cm3, F(000) = 1968 and m(MoKa) = 1.368 mm-1. The structure was solved by direct methods and refined by full-matrix least-squares techniques. The final R = 0.0734 and wR = 0.1954 for 1606 observed reflections with I ≥2.0s(I). The crystal structure revealed that the [Cu2(m-NO2)(aepy)4]3+ cation consists of two square-based pyramidal copper (Ⅱ) atoms bridged by one nitrate anion. The distance between the two copper atoms (Cu(1)…Cu(1A)) is 5.373 (2) ?展开更多
Some spectral properties and luminescence intensities of Tb 3+ chelates of substituted pyridine 2, 6 dicarboxylic acids and 4 phenyl pyridine 2, 6 dicarboxylic acid analogues were measured in some solutions...Some spectral properties and luminescence intensities of Tb 3+ chelates of substituted pyridine 2, 6 dicarboxylic acids and 4 phenyl pyridine 2, 6 dicarboxylic acid analogues were measured in some solutions (H 2O and EtOH etc.) by synergistic effect of EDTA. The substitution at the aromatic ring has a significant effect upon the observed luminescence intensities, excitation wavelengths, and lifetime of the complexes. Moreover, the changes in the environment cause great variation in those properties of certain Tb 3+ chelates. The results show that some of hte chelates (4 acetaminopoxypyridine 2, 6 dicarboxylic acid, 4 ethoxypyridine 2, 6 dicarboxylic acid and 4 methoxypyridine 2, 6 dicarboxylic acid etc.) have a stronger emission and longer lifetime at room temperature and may thus be used as perfectly sensitizers in fluorescence analysis.展开更多
Reducing 2, 6-pyridinedicaboxylic acid diethyl ester to 2,6-di(hydroxymethyl)pyridine was carried out by using NaBH4/CaCl2 as reducing agent. It is an improved and efficient method. The yield is up to 91%.
Ionic, electronic and mixed (ionic-electronic) conductivities of blends of poly(2-vinyl pyridine) (P2VP) and poly(ethylene oxide) (PEO) with high molecular weight after doped with LiClO4, TCNQ or LiClO4 and TCNQ were ...Ionic, electronic and mixed (ionic-electronic) conductivities of blends of poly(2-vinyl pyridine) (P2VP) and poly(ethylene oxide) (PEO) with high molecular weight after doped with LiClO4, TCNQ or LiClO4 and TCNQ were investigated. Effects of LiClO4 and TCNQ concentrations on the conductivity of PEO/P2VP/LiClO4 or TCNQ blend were studied. The ionic conductivity of PEO/P2VP/LiClO4 blend increases with increasing PEO content. At a Li/ethylene bride molar ratio of 0.10 and a TCNQ/2-vinyl pyridine molar ratio of 0.5, the mixed conductivity of PEO/P2VP/LiClO4/TCNQ is higher than the total of ionic conductivity of PEO/P2VP/LiClO4 and electronic conductivity of PEO/P2VP/TCNQ when the weight ratio of PEO and P2VP is 6/4 or 5/5. Scanning electron microscopy (SEM) on the broken cross-section of the PEO/P2VP/LiClO4 blend and differential scanning calorimetry (DSC) results show that LiClO4 could act as a compatibilizer in the blend.展开更多
基金supported by the Natural Science Foundation of Shandong Province(ZR2011BL020,ZR2012CM019)National Natural Science Foundation of China(21451001)Key Discipline and Innovation Team of Qilu Normal University
文摘One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characterized by elemental analysis(EA), IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. The crystal of 1 crystallizes in monoclinic, space group P21/n with a = 12.2860(5), b = 13.8246(6), c = 19.0140(8) A, β = 104.3870(1)°, V = 3128.2(2) A3, Z = 4, C32H28N7 Ni O8, Mr = 697.32, Dc = 1.481 g/cm^3, F(000) = 1444 and μ(Mo Kα) = 0.684 mm-1. The final R = 0.0704 and w R = 0.1764 for 5485 observed reflections with I 2σ(I) and R = 0.1087 and wR = 0.2010 for all data. Topology analysis reveals that complex 1 is a 3D 2-fold interpenetrated {4^4·6^6}-nov net based on the 1D [Ni(OTP)]n chain and the 2D [Ni2(bib)3]n sql sheet. And the variable-temperature magnetic susceptibility measurements exhibit weak antiferromagnetic coupling interaction.
基金Supported by the Excellent Young Teachers Program of MOETrans- century Program me Foundation for the Talentsby the State Education Ministry and Excellent Youth Foundation of Jilin Province
文摘The geometrical structures of 2 (2 hydroxyphenyl) pyridine(PP) and its protonation states were optimized by means of the B3LYP/6 31G(d) method. For all the selected systems, the existence of H bond is in favor of the stability of the systems. On the basis of the optimized geometrical structures, their electronic spectrum properties were studied by time dependent density functional theory(TD DFT) methosd via a hybrid function of B3LYP and 6 31G(d) basis set. The TD DFT calculation result predicts the absorption spectrum of PP at 324 nm(3.82 eV), which is in very good agreement with the experimental value of 322 nm( 3.85 eV ) determined in solvent chloroform. The absorption spectra of the two protonation states both exert a red shift in various pH media.
基金Supported by NNSFC(21272167 and 21201127)the Priority Academic Program Development of Jiangsu Higher Education Institution,Graduate Education Innovation Project in Jiangsu Province(CXZZ12_0808 and CXLX12_0784)KLSLRC(KLSLRC-KF-13-HX-1)
文摘The employment of N-hydroxy-pyridine-2-carboxamidine in the coordination chemistry of zinc(II), nickel(II) and manganese(II) under solvothermal conditions is reported. Four complexes of compositions, [Zn2(O2CMe)3{(py)C(NH2)NOH}4](OH) (1), [Zn4(OH)2{(py)C(NH2)- NO}4CI2]'3MeCN (2), [Ni(SO4)(H20){(py)C(NH2)NOH}2]'H2O (3) and [Mn(SO4){(py)C(NH2)- NOH}2]n (4), have been synthesized by rationally choosing different metal salts and dexterously employing acetate and sulfate ions as the bridging groups. Luminescent properties for 2 suggested strong emission in the solid state at room temperature. Variable temperature (2.0-300 K) magnetic studies for the linear chain complex 4 indicate weak antiferromagnetic Mn(Ⅱ)...Mn(Ⅱ) exchange interactions.
基金supported by the National Basic Research Program of China ("973" Program) (Grant No. 2009CB219504-03)the National Natural Science Foundation of China (Grant No 51106054)the Colleges and Universities High-level Talents Program of Guangdong
文摘In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the combined use of KHIs and some synergists, which would enhance KHIs’ inhibitory effect on both hydrate nucleation and hydrate crystal growth. In this study, a novel kind of KHI copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s (HGs) is used in conjunction with TBAB to show its high performance on hydrate inhibition. The performance of HGs with different monomer ratios in structure II tetrahydrofuran (THF) hydrate is investigated using kinetic hydrate inhibitor evaluation apparatus by step-cooling method and isothermal cooling method. With the combined gas hydrate inhibitor at the concentration of 1.0 wt%, the induction time of 19 wt% THF solution could be prolonged to 8.5 h at a high subcooling of 6℃. Finally, the mechanism of HGs inhibiting the formation of gas hydrate is proposed.
基金supported by the National Natural Science Foundation of China (No. 21101097)Natural Science Foundation of Shandong Province (ZR2010BQ023)the State Key Laboratory of Solid Lubrication (No. 0701)
文摘Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxalic acid (H2ox) afford three novel supramolecular polymers (CPs), namely, {[M2(ox)(L)2][bdc][M2(Hox)2(OH)(H2O)4]·3H2O}n (M = Mn for 1, Co for 2, Cd for 3). Single-crystal X-ray diffraction analysis reveals that complexes 1-3 are isostructural and the 3D supramolecular structure was connected through non-covalent interactions. With the help of H2ox, the L ligands cheated with center atoms forming a butterfly [M2(ox)(L)2]2+ building block. The bdc2- ligand linked with the unprecedented [M2(Hox)2(OH)2(H2O)4] units through strong O-H...O hydrogen bonds forming a zigzag chain, which are further connected through π-π interactions between L and bdc2- ligands to form a 3D supramolecular structure. Moreover, elemental analyses, IR, thermogravimetric, PXRD and luminescence have been investigated.
基金funded by the National Natural Science Foundation of China(No.21002090)the Natural Science Foundation of Zhejiang Province(No.LY16C140007)the public program of Science and Technology of Zhejiang Province(2014C31127,2013C32SA700134)
文摘The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence of Na OH, and its structure was determined by X-ray diffraction analysis. The crystal is of triclinic system, space group P1 with a = 6.8264(6), b = 7.5890(4), c = 13.0960(7) A, α = 93.447(4), β = 98.772(6), γ = 92.615(6)o, V = 668.26(8) A3, Z = 2, the final R = 0.035 and wR = 0.09 for 2259 observed reflections with I 〉 2σ(I). The preliminary biological test showed that the title compound has activities against Stemphylium lycopersici(Enjoji) Yamamoto, Fusarium oxysporum. sp. cucumebrium, and Botrytis cinerea with inhibitory to be 51.19%, 62.02% and 15.56%, respectively.
基金Supported by the Science and Technology Fund of Hengyang Science and Technology Bureau (No. 2008KS035)the Construct Program of the Key Discipline in Hunan Province
文摘A new trinuclear nickel complex,[Ni3(pdc)3(2,2'-bipy)3(H2O)2]·2H2O(H2pdc = pyridine 2,6-dicarboxylic acid,2,2'-bipy = 2,2'-bipyridine) has been hydrothermally synthesized and characterized by IR,elemental analysis and X-ray diffraction methods.Crystal data for this complex:monoclinic,space group P21/n,a = 21.206(4),b = 10.002(2),c = 28.066(6),β = 108.18(3)°,C51H41N9Ni3O16,Mr = 1212.06,V = 5.656(2) nm3,Dc = 1.423 g·cm-3,μ(MoKα) = 1.062 mm-1,Z = 4,F(000) = 2488,GOOF = 1.034,the final R = 0.0543 and wR = 0.1237 for 6149 observed reflections with Ⅰ 〉 2σ(Ⅰ).In the complex,three nickel(Ⅱ) ions are bridged by the pyridine 2,6-dicarboxylic acid groups,and all nickel(Ⅱ) ions are seven-coordinated by nitrogen atoms of 2,2'-bipyridine and pyridine 2,6-dicarboxylic acid and oxygen atoms from pyridine 2,6-dicarboxylic and water to adopt a severely distorted pentagonal bipyramidal geometry.The emission and excitation peaks of the complex in ethanol solutions are located at 336 and 316 nm,respectively.
基金Supported by the Scientific Research Foundation of Higher Education Institutions of Ningxia(No.NGY2017004)the National Natural Science Foundation of China(Nos.21763022 and 50564043)the Major Innovation Projects for Building First-class Universities in China’s Western Region(No.ZKZD2017003)
文摘A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.
文摘A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.
基金Supported by the National Natural Science Foundation of China (No. 20271043)Natural Science Foundation of Shandong Province (Y2007B26)
文摘A three-dimensional coordination polymer [Mn2(μ1.3-N3)4(μ-PP)2]n (PP = 3-(pyrazin-2-yloxy)-pyridine) has been synthesized with 3-(pyrazin-2-yloxy)-pyridine and azide anion as mixed bridge ligand, and its crystal structure was determined by X-ray crystallography. The crystal data: triclinic system, space group P1, with a = 6.794(4), b = 9.885(6), c = 9.947(6) A, α = 64.170(6), β= 84.190(8), γ= 85.319(8)°, V = 597.7(6)A^3, Z = 1, C18H14Mn2N18O2, Mr = 624.35, Dc = 1.735 g/cm^3, F(000) = 314 and μ = 1.117 mm^-1. In the crystal, the azide anion acts as a bridge ligand and makes adjacent Mn(Ⅱ) ions connect into a two-dimensional sheet on the ab plane, then 3-(pyrazin-2-yloxy)-pyridine serves as a bidentate bridge ligand to connect neighboring sheets along
基金Project(20761002) supported by the National Natural Science Foundation of China
文摘Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion.
基金supported by the National Natural Science Foundation of China (No. 20671016)Education Committee of Jilin Province "11th Five-year Plan" Natural Science Foundation (No. 2006124)
文摘The title compound, [Ni(C8N3H7)3]4[Mo8O26]2·6H2O 1, has been synthesized from the reaction of 2-(1H-pyrazol-3-yl)-pyridine (L) with (NH4)2MoO4·2H2O and NiCl2·6H2O. Elemental analysis, IR, UV spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the compound. Crystal data: C96H96Mo16N36Ni4O58, Mr = 4451.97, monoclinic system, space group P21/n, a = 20.846(5), b = 14.825(5), c = 23.122(5) A ,β= 91.594(5)°, V = 7143(3)A^3, Z = 2, F(000) = 4344, Dc = 2.070 g/cm^3,μ = 1.968 mm^-1, R = 0.0452 and wR = 0.1056 for 17102 independent reflections (Rint = 0.0442) and 11074 observed reflections (I 〉 2σ(I)). Structural analysis indicates that two kinds of octamolybdates ([α-Mo8026]^4- and [β-Mo8026]^4-) co-exist in the compound. This is the first example of a supramolecular structure containing L complex as well as both α- and β-octamolybdate clusters.
基金This project was financially supported by the Postdoctoral Science Foundation of China K. C. Wong Education Foundation+1 种基金 the National Natural Science Foundation of China and the Natural Science Foundation of Fujian Province and CAS
文摘The title compound [Cu2(m-NO2)(aepy)4](ClO4)3 (Cu2C28H40N9Cl3O14, Mr = 960.12, aepy = 2-(2-aminoethyl)pyridine) was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group C2/c with cell parameters: a = 21.958(3), b = 12.205(2), c = 15.180(3) ? b = 106.06(1), V = 3909.5(12) ?, Z = 4, Dc = 1.631 g/cm3, F(000) = 1968 and m(MoKa) = 1.368 mm-1. The structure was solved by direct methods and refined by full-matrix least-squares techniques. The final R = 0.0734 and wR = 0.1954 for 1606 observed reflections with I ≥2.0s(I). The crystal structure revealed that the [Cu2(m-NO2)(aepy)4]3+ cation consists of two square-based pyramidal copper (Ⅱ) atoms bridged by one nitrate anion. The distance between the two copper atoms (Cu(1)…Cu(1A)) is 5.373 (2) ?
文摘Some spectral properties and luminescence intensities of Tb 3+ chelates of substituted pyridine 2, 6 dicarboxylic acids and 4 phenyl pyridine 2, 6 dicarboxylic acid analogues were measured in some solutions (H 2O and EtOH etc.) by synergistic effect of EDTA. The substitution at the aromatic ring has a significant effect upon the observed luminescence intensities, excitation wavelengths, and lifetime of the complexes. Moreover, the changes in the environment cause great variation in those properties of certain Tb 3+ chelates. The results show that some of hte chelates (4 acetaminopoxypyridine 2, 6 dicarboxylic acid, 4 ethoxypyridine 2, 6 dicarboxylic acid and 4 methoxypyridine 2, 6 dicarboxylic acid etc.) have a stronger emission and longer lifetime at room temperature and may thus be used as perfectly sensitizers in fluorescence analysis.
文摘Reducing 2, 6-pyridinedicaboxylic acid diethyl ester to 2,6-di(hydroxymethyl)pyridine was carried out by using NaBH4/CaCl2 as reducing agent. It is an improved and efficient method. The yield is up to 91%.
基金Project supported by the National Natural Science Foundation of China.
文摘Ionic, electronic and mixed (ionic-electronic) conductivities of blends of poly(2-vinyl pyridine) (P2VP) and poly(ethylene oxide) (PEO) with high molecular weight after doped with LiClO4, TCNQ or LiClO4 and TCNQ were investigated. Effects of LiClO4 and TCNQ concentrations on the conductivity of PEO/P2VP/LiClO4 or TCNQ blend were studied. The ionic conductivity of PEO/P2VP/LiClO4 blend increases with increasing PEO content. At a Li/ethylene bride molar ratio of 0.10 and a TCNQ/2-vinyl pyridine molar ratio of 0.5, the mixed conductivity of PEO/P2VP/LiClO4/TCNQ is higher than the total of ionic conductivity of PEO/P2VP/LiClO4 and electronic conductivity of PEO/P2VP/TCNQ when the weight ratio of PEO and P2VP is 6/4 or 5/5. Scanning electron microscopy (SEM) on the broken cross-section of the PEO/P2VP/LiClO4 blend and differential scanning calorimetry (DSC) results show that LiClO4 could act as a compatibilizer in the blend.