A series of salicylaldimines, synthesized in high yield via microwave-assisted condensation of salicylaldehyde and 2-alkoxyaniline were allowed to react with nickel chloride to form six-coordinated nickel complexes. T...A series of salicylaldimines, synthesized in high yield via microwave-assisted condensation of salicylaldehyde and 2-alkoxyaniline were allowed to react with nickel chloride to form six-coordinated nickel complexes. These nickel complexes were carefully characterized, and the solid structure of la was elucidated by X-Ray diffraction. Activated with MAO, the nickel complexes showed good activity for homopolymerization of norbornene. Reaction parameters, such as the ratio of nickel precursor to MAO, monomer concentration, reaction time and the reaction temperature, as well as the nature of the ligands were found to have significant effects on the catalytic activity and some properties of the resulting polynorbornene.展开更多
Two homochiral metallosalen complexes, Ni（salen） （salen = （1R,2R）-（-）-diamino- cyclohexane-N,N′-bis（3-tert-butyl-5-（4′-benzoic acid）-salicylidene） 1 and Cu（salen） 2, have been synthesized and characteri...Two homochiral metallosalen complexes, Ni（salen） （salen = （1R,2R）-（-）-diamino- cyclohexane-N,N′-bis（3-tert-butyl-5-（4′-benzoic acid）-salicylidene） 1 and Cu（salen） 2, have been synthesized and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 4. For 1, a = 12.082（2）, b = 15.447（3）, c = 18.784（4）A^°, V= 3505.7（12）A^°3, Mr = 731.50, Dc = 1.386 g/cm^3, μ = 0.606 mm^-1, F（000） = 1544, the final GOOF = 1.043, R = 0.0496 and wR = 0.1248 for 4791 observed reflections with I 〉 2σ（I）. For 2, a = 12.181（2）, b = 15.501（3）, c = 18.877（4） A^°, V = 3564.3（12）A^°3, Mr = 736.33, Dc = 1.372 g/cm^3, μ = 0.665 mm^-1, F（000） = 1548, the final GOOF = 1.062, R = 0.0575 and wR = 0.1508 for 4562 observed reflections with I 〉 2σ（I）. The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. An infinite two-dimensional network is generated by hydrogen bonding interactions and intermolecular π…π interactions.展开更多
The complexes of bis[N-alkyl-2-hydroxonapthaldimine]nickel(II) (N-alkyl = methyl, ethyl, propyl, butyl or pentyl) were synthesized and their volatilization in N2 atmosphere was demonstrated by the TG-based transpirati...The complexes of bis[N-alkyl-2-hydroxonapthaldimine]nickel(II) (N-alkyl = methyl, ethyl, propyl, butyl or pentyl) were synthesized and their volatilization in N2 atmosphere was demonstrated by the TG-based transpiration technique. The equilibrium vapor pressure of the complexes over a temperature span of 470 - 590 K was determined by adapting a horizontal dual arm single furnace thermoanalyser as a transpiration apparatus. It yielded as 153.1 (±1.9), 122.9 (±0.3), 147.6 (±10.7), 151.8 (±10.9) and 114.7 (±5.3) k·Jmol–1 respectively. The entropies of vaporization for these complexes as calculated from the intercept of the linear fit expressions were found to be 319.7 (±3.9), 229.9 (±5.8), 317.8 (±17.2), 319.7 (±19.1) and 254.6 (±9.6) Jmo–1·K–1 respectively. The non-isothermal vaporization activation energy was determined from Arrhenius and Coats-Redfern methods.展开更多
In the practical use for the production of the α-olefins, it is highly desired to develop a novel heterogeneous catalyst system. The metal complexes immobilized into the clay interlayers show a great potential as het...In the practical use for the production of the α-olefins, it is highly desired to develop a novel heterogeneous catalyst system. The metal complexes immobilized into the clay interlayers show a great potential as heterogeneous catalysts due to their excellent processability. In this study, nine types of heterogeneous procatalyst Ln/Ni2+-micas were synthesized via a one-pot preparation method, which includes both the condensation reaction of the ligand derivatives and the intercalation of the ligands into the Ni2+ ion-exchanged fluorotetrasilicic mica interlayer. The ligand structures of the prepared procatalysts were [Ln: R-N = C(Nap)-C(Nap) = N-R] [(Nap = 1,8-naphthdiyl) (L1, R = 2-MePh;L2, R = 2-FPh;L3, R = 2-BrPh;L4, R = 4-MePh;L5, R = 4-FPh;L6, R = 4-BrPh;L7, R = 2,4-F2Ph;L8, R = 2,4-Br2Ph;L9, R = 2,6-F2Ph). At 50℃ and 0.7 MPaethylene pressure, the triisobutylaluminum-activated L1-L6/Ni2+-mica showed a catalytic activity for the ethylene oligo-/polymerization in the range of 334 - 549 g-ethylene•g-cat–1•h–1. A high catalyst activity was obtained when the substituent having a larger steric bulk than that of a methyl substituent was introduced at the ortho-position of the aryl rings. The introduction of the fluorine substituent as a strong electron-withdrawing group to the para-position also increased the catalytic activity. The L2, L4, L5, and L6/Ni2+-micas showed moderate selectivities to oligomers consisting of C4-C20 in the range of 19.9 - 41.6 wt% at 50℃. The calculated Schulz-Flory constants α based on the mole fraction of C12 and C14 were within 0.61 - 0.78.展开更多
The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are ...The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP.展开更多
The complex [Ni(L)(N3)2](H_2O (L=N,N(-Bis(2-pyridylaldehyde) condensation 1,3-diaminopropane) was synthesized by the reaction of NiCl2(6H_2O with 2-pyridylaldehyde and 1,3-diaminopropane and sodium azide in the ethan...The complex [Ni(L)(N3)2](H_2O (L=N,N(-Bis(2-pyridylaldehyde) condensation 1,3-diaminopropane) was synthesized by the reaction of NiCl2(6H_2O with 2-pyridylaldehyde and 1,3-diaminopropane and sodium azide in the ethanol. A single-crystal X-ray study shows that the complex is a six-coordinated nickel (II) with an octahedral environment compound (C15H18N10NiO). The crystal is orthogonal, space group Pbca, with unit cell parameters: a = 13.577(3), b = 15.261(3), c = 17.554(4) ?, V= 3637(1) ?3, Z=8, Mr=413.10, Dc=1.509 g/cm3, ( = 1.096 mm－1, F(000) = 1712, T = 293(2)K, R = 0.0411, wR = 0.1048 for 2888 reflections with I >2( (I). The distances between Ni and N atoms (N(1), N(2), N(3), N(4)) range from 2.050(2) to 2.140(2)?. The distances of Ni-N(5) and Ni-N(8) are 2.115(3) and 2.133(3)?, respectively. The solvent molecule H_2O(O(1)) is linked by hydrogen bonds with O(1) and N(5) and N(8) atoms. Their distances are 2.881(+x, +y, +z) and 2.893(0.5+x, y, 0.5+z)?, respectively.展开更多
The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-t...The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF.展开更多
Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane（MMAO）, were tested in the polymerization of higher α-olefin（1-hexene, 1-decene and 1-hexadec...Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane（MMAO）, were tested in the polymerization of higher α-olefin（1-hexene, 1-decene and 1-hexadecene） under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers（42-88/1000 C） with high molecular weights（Mn：（4.3-15.2） × 10^4 g·mol^-1） and narrow molecular weight distribution（Mw/Mn = 1.13-1.29, RT）, which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction.展开更多
A new mixed-ligand nickel（Ⅱ） complex, [Ni（L）（DCA）（H2O）]·2H2O （L = C8H9N3, 2-aminomethyl-benzimidazole, DCA2- = 7-oxabicyclo[2,2,1]heptane-2,3-dicarboxylate, demethylcantharate, C8H8O5）, has been synthe...A new mixed-ligand nickel（Ⅱ） complex, [Ni（L）（DCA）（H2O）]·2H2O （L = C8H9N3, 2-aminomethyl-benzimidazole, DCA2- = 7-oxabicyclo[2,2,1]heptane-2,3-dicarboxylate, demethylcantharate, C8H8O5）, has been synthesized and characterized. The structure of the complex was determined by single-crystal X-ray diffraction. It is of monoclinic system, space group P21/c with a = 7.7211（7）, b = 12.0799（12）, c = 19.7867（19）, β = 100.390（6）°, V = 1815.2（3） nm3, Dc = 1.625 g·cm-3, Ζ = 4, F（000） = 928, R = 0.0314 and wR = 0.0822. In addition, the interaction between the complex and DNA was studied by means of fluorescence spectra and viscosity. The results indicate that the complex binds to DNA by the mode of partial intercalation with the Stern-Volmer constants Ksv of 3.81 × 104 mol·L-1.展开更多
Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of th...Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed.展开更多
Emulsion copolymerization of styrene and ethylene catalyzed by a series of neutral nickel(Ⅱ) complexes was carried out in an aqueous system to give high-molecular-weight copolymers.The copolymers and emulsions were c...Emulsion copolymerization of styrene and ethylene catalyzed by a series of neutral nickel(Ⅱ) complexes was carried out in an aqueous system to give high-molecular-weight copolymers.The copolymers and emulsions were characterized by an array of techniques including NMR,GPC,TEM,WAXD and DSC.The results indicate that the copolymers obtained are mostly block copolymers of polyethylene with random insertion of styrene units,and their M_W is in the range of 10~5-10~6.By enhancing the electron withdrawing of the s...展开更多
The title nickel complex I and cobalt complex II were obtained separately from the direct reaction of D-（＋）-leucinol with Ni（II） chloride and L-（-）-leucinol with Co（II） acetate tetra- hydrate in anhydrous met...The title nickel complex I and cobalt complex II were obtained separately from the direct reaction of D-（＋）-leucinol with Ni（II） chloride and L-（-）-leucinol with Co（II） acetate tetra- hydrate in anhydrous methanol. The crystal structures of I and II were determined by single-crystal X-ray diffraction and further characterized by elemental analysis and IR. For I： [Ni（C18H45N3O3）]Cl2, orthorhombic, P212121, a = 11.2807（9）, b = 14.7115（11）, c = 16.3580（13） A, V = 2714.7（4） A3, Z = 4, Pcalcd = 1.177 Mg/m3, the final R = 0.0407, and 16539 reflections observed with I 〉 2σ（/）; For II： [Co（C45HI08N6015）], trigonal, R3：H, a = 23.981（3）, b =23.981（3）, c = 10.8925（15） A, γ = 120°, V = 5425.1（14） A3, Z = 3, Pcalcd = 1.002 Mg/m3, the final R = 0.0625 for 16556 observed reflections with I 〉 2σ（I）. The complexes were then used to catalyze the Henry reaction and obtained good catalytic results. The catalytic activity of the complexes was determined by IH NMR. And research is going towards the application to other organic reactions such as cyanosilylation reaction.展开更多
A new α-diimine ligand 1a, bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2a, {bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene}d...A new α-diimine ligand 1a, bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2a, {bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene}dibromo- nickel were successfully synthesized, and characterized by 1H NMR, 13C NMR, Fourier transform infrared spectroscope（FTIR）, elemental analysis and X-ray photoelectron spectroscopy（XPS）. α-Diimine ligand 1b, bis[N,N′-（2,6- dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2b, {bis[N,N′-（2,6-dimethyl- phenyl）imino]-2,3-butanediylidene}dibromonickel were also synthesized and characterized for comparison. The pre-catalyst 2a with sterically bulky, electron-donating group tert-butyl, activated by diethylaluminum chloride （DEAC） and tested in the polymerization of ethylene, was very highly active[2.01×107 g PE/（mol Ni？h？0.1 MPa）] and led to a very highly branched polyethylene（ca. 35―103 branches/1000 C）. The state of the polyethylene obtained varied from plastic, elastomer polymers to the oil-like hyperbranched polymers.展开更多
Metal skeletons,such as Nickel Foam(NF) has attracted worldwide interests as stable host for lithium metal anode because of its high stability,large specific surface area and high conductivity.However,most metal skele...Metal skeletons,such as Nickel Foam(NF) has attracted worldwide interests as stable host for lithium metal anode because of its high stability,large specific surface area and high conductivity.However,most metal skeletons have lithophobic surface and uneven current distribution that result in sporadic lithium nucleation and uncontrolled dendrites growth.Herein,we describe a sequential immersing strategy to generate interwoven Nickel(Ⅱ)-dimethylglyoxime(Ni-DMG) nanowires at NF to obtain composite skeleton(NDNF),which can be used as an stable host for Li metal storage.The Ni-DMG has proved effective to realize uniform lithium nucleation and dendrite-free lithium deposition.Combing with the three dimensional(3 D) hierarchical porous structure,the composite host shows a significantly improved coulombic efficiency(CE) than pristine commercial nickel foam.Moreover,the corresponding Li‖Li symmetrical cells can run more than 700 h with low voltage hysteresis 22 mV at 1.0 mA/cm^(2),and Li@NDNF‖LiFePO;full-cell exhibits a high capacity retention of 82.03% at 1.0 C during 630 cycles.These results proved the effectiveness of metal-organic complexes in governing Li metal growth and can be employed as a new strategy for dendrite-free Li metal anode and safe Li metal batteries(LMBs).展开更多
A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precur...A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precursors for ethylene polymerization in the presence of methylaluminoxane(MAO).The catalysts containing ortho-alkyl-substituents afford high molecular weight branched polyethylenes as well as a certain amount of oligomers.Enhancing the steric bulk of the alkyl substituent of the catalyst resulted in...展开更多
The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 11...The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 116.75(3)°, V = 1545.7(5) ?, Z = 4, Mr = 380.04, F(000) = 784, Dc = 1.633 g/cm3 and μ(MoKα) = 1.279 mm–1. The structure was refined to R = 0.0472 and wR = 0.0893 for 2571 observed reflections with I > 2σ(I). The absolute structure Flack parameter X is 0.01(2). In this crystal structure, strong face-to-face π-π stacking interactions between adjacent molecules lead to a one-dimensional chain structure.展开更多
Two homochiral mercury （1） and cadmium （2） complexes derived from chiral twisted biphenyl pyridine ligand （3,3＇-bipyridine-5,5＇,6,6＇-tetramethyl-2,2＇-dimethoxy-1,1＇-biphenyl） have been synthesized and chara...Two homochiral mercury （1） and cadmium （2） complexes derived from chiral twisted biphenyl pyridine ligand （3,3＇-bipyridine-5,5＇,6,6＇-tetramethyl-2,2＇-dimethoxy-1,1＇-biphenyl） have been synthesized and characterized by IR, microanalysis, TGA, UV-Vis, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 2. For 1, a = 14.2038（16）, b = 14.3630（17）, c = 7.0257（8）, V = 1433.3（3）3, Mr = 878.91, Dc = 2.037 g/cm3, μ = 7.549 mm-1, F（000） = 824, the final GOF = 1.017, R = 0.0296 and wR = 0.0645 for 2925 observed reflections with I 2σ（I）. For 2, a = 14.212（3）, b = 14.392（3）, c = 7.0498（14）, V = 1442.0（5）3, Mr = 790.72, Dc = 1.821 g/cm3, μ = 2.924 mm–1, F（000） = 760, the final GOF = 1.075, R = 0.0340 and wR = 0.0834 for 3144 observed reflections with I 2σ（I）. The crystal structures of 1 and 2 are isostructural and each adopts a two-dimensional supramolecular network which contains the C–H···π interactions.展开更多
The reactions of chiral four-coordinated nickel（Ⅱ） complex [Ni（RR-L）]（ClO4）2/[Ni（SS- L）]（ClO4）2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni（RR-L）（β-d-HPhe）]...The reactions of chiral four-coordinated nickel（Ⅱ） complex [Ni（RR-L）]（ClO4）2/[Ni（SS- L）]（ClO4）2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni（RR-L）（β-d-HPhe）]（ClO4）2（1） and [Ni（SS-L）（β-l-HPhe）]（ClO4）2（2）, respectively（L = 5,5,7, 12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, HPhe = phenylalanine）. Single-crystal X-ray diffraction analyses revealed that the nickel（Ⅱ） atom displays a distorted octahedral coordination geometry by coordinating with four nitrogen atoms of L in a folded configuration, and two carboxylate oxygen atoms of β-d/l-HPhe in cis-position in both complexes. The monomers of [Ni（RR-L）（β-d-HPhe）]2＋ and [Ni（SS-L）（β-l-HPhe）]2＋ are connected through intermolecular hydrogen bonds to generate one-dimensional zigzag chains, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy.展开更多
Two coordination polymers, [ML2]n （M = Co （1）, Ni （2）, L = 3-aminobenzoic acid anion）, were synthesized by hydrothermal reaction, and their crystal structures were determined by X-ray diffraction analysis. Both ...Two coordination polymers, [ML2]n （M = Co （1）, Ni （2）, L = 3-aminobenzoic acid anion）, were synthesized by hydrothermal reaction, and their crystal structures were determined by X-ray diffraction analysis. Both compounds crystallize in monoclinic, space group P21/n with a = 8.8029（8）, b = 4.5297（4）, c = 15.2002（14）A°, β= 105.6280（10）°, C14H12CoN2O4, Mr= 331.19, Z= 2, V = 583.69（9）A°^3 Dc= 1.884 g/cm^3,μ=1.490 mm^-1, F（000） = 338, R = 0.0234 and wR = 0.0679 for 1337 observed reflections （I 〉 2σ（I）） for 1, and a = 8.7501（7）, b = 4.5191（4）, c = 15.1448（12） A°,β = 105.7730（10）° C14H12 NiN2O4, Mr = 330.97, Z = 2, V = 576.31（8）A°3, Dc = 1.907 g/cm^3,μ = 1.703 mm^-1, F（000） = 340, R = 0.0206 and wR = 0.0572 for 1209 observed reflections （I 〉 2σ（I）） for 2. In the title complexes, the M （Ⅱ） ion presents an octahedral geometry with four oxygen donors in the equatorial positions and two nitrogen donors in the axial positions. Each of the complexes has a two-dimensional network structure that is formed by the bridging of the ligand in a μ3-bridging mode via its amino and carboxyl groups.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.20272062 and 20473099).
文摘A series of salicylaldimines, synthesized in high yield via microwave-assisted condensation of salicylaldehyde and 2-alkoxyaniline were allowed to react with nickel chloride to form six-coordinated nickel complexes. These nickel complexes were carefully characterized, and the solid structure of la was elucidated by X-Ray diffraction. Activated with MAO, the nickel complexes showed good activity for homopolymerization of norbornene. Reaction parameters, such as the ratio of nickel precursor to MAO, monomer concentration, reaction time and the reaction temperature, as well as the nature of the ligands were found to have significant effects on the catalytic activity and some properties of the resulting polynorbornene.
基金supported by the Natural Science Foundation of Anhui Province (No. KJ2008B166)
文摘Two homochiral metallosalen complexes, Ni（salen） （salen = （1R,2R）-（-）-diamino- cyclohexane-N,N′-bis（3-tert-butyl-5-（4′-benzoic acid）-salicylidene） 1 and Cu（salen） 2, have been synthesized and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 4. For 1, a = 12.082（2）, b = 15.447（3）, c = 18.784（4）A^°, V= 3505.7（12）A^°3, Mr = 731.50, Dc = 1.386 g/cm^3, μ = 0.606 mm^-1, F（000） = 1544, the final GOOF = 1.043, R = 0.0496 and wR = 0.1248 for 4791 observed reflections with I 〉 2σ（I）. For 2, a = 12.181（2）, b = 15.501（3）, c = 18.877（4） A^°, V = 3564.3（12）A^°3, Mr = 736.33, Dc = 1.372 g/cm^3, μ = 0.665 mm^-1, F（000） = 1548, the final GOOF = 1.062, R = 0.0575 and wR = 0.1508 for 4562 observed reflections with I 〉 2σ（I）. The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. An infinite two-dimensional network is generated by hydrogen bonding interactions and intermolecular π…π interactions.
文摘The complexes of bis[N-alkyl-2-hydroxonapthaldimine]nickel(II) (N-alkyl = methyl, ethyl, propyl, butyl or pentyl) were synthesized and their volatilization in N2 atmosphere was demonstrated by the TG-based transpiration technique. The equilibrium vapor pressure of the complexes over a temperature span of 470 - 590 K was determined by adapting a horizontal dual arm single furnace thermoanalyser as a transpiration apparatus. It yielded as 153.1 (±1.9), 122.9 (±0.3), 147.6 (±10.7), 151.8 (±10.9) and 114.7 (±5.3) k·Jmol–1 respectively. The entropies of vaporization for these complexes as calculated from the intercept of the linear fit expressions were found to be 319.7 (±3.9), 229.9 (±5.8), 317.8 (±17.2), 319.7 (±19.1) and 254.6 (±9.6) Jmo–1·K–1 respectively. The non-isothermal vaporization activation energy was determined from Arrhenius and Coats-Redfern methods.
文摘In the practical use for the production of the α-olefins, it is highly desired to develop a novel heterogeneous catalyst system. The metal complexes immobilized into the clay interlayers show a great potential as heterogeneous catalysts due to their excellent processability. In this study, nine types of heterogeneous procatalyst Ln/Ni2+-micas were synthesized via a one-pot preparation method, which includes both the condensation reaction of the ligand derivatives and the intercalation of the ligands into the Ni2+ ion-exchanged fluorotetrasilicic mica interlayer. The ligand structures of the prepared procatalysts were [Ln: R-N = C(Nap)-C(Nap) = N-R] [(Nap = 1,8-naphthdiyl) (L1, R = 2-MePh;L2, R = 2-FPh;L3, R = 2-BrPh;L4, R = 4-MePh;L5, R = 4-FPh;L6, R = 4-BrPh;L7, R = 2,4-F2Ph;L8, R = 2,4-Br2Ph;L9, R = 2,6-F2Ph). At 50℃ and 0.7 MPaethylene pressure, the triisobutylaluminum-activated L1-L6/Ni2+-mica showed a catalytic activity for the ethylene oligo-/polymerization in the range of 334 - 549 g-ethylene•g-cat–1•h–1. A high catalyst activity was obtained when the substituent having a larger steric bulk than that of a methyl substituent was introduced at the ortho-position of the aryl rings. The introduction of the fluorine substituent as a strong electron-withdrawing group to the para-position also increased the catalytic activity. The L2, L4, L5, and L6/Ni2+-micas showed moderate selectivities to oligomers consisting of C4-C20 in the range of 19.9 - 41.6 wt% at 50℃. The calculated Schulz-Flory constants α based on the mole fraction of C12 and C14 were within 0.61 - 0.78.
文摘The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP.
文摘The complex [Ni(L)(N3)2](H_2O (L=N,N(-Bis(2-pyridylaldehyde) condensation 1,3-diaminopropane) was synthesized by the reaction of NiCl2(6H_2O with 2-pyridylaldehyde and 1,3-diaminopropane and sodium azide in the ethanol. A single-crystal X-ray study shows that the complex is a six-coordinated nickel (II) with an octahedral environment compound (C15H18N10NiO). The crystal is orthogonal, space group Pbca, with unit cell parameters: a = 13.577(3), b = 15.261(3), c = 17.554(4) ?, V= 3637(1) ?3, Z=8, Mr=413.10, Dc=1.509 g/cm3, ( = 1.096 mm－1, F(000) = 1712, T = 293(2)K, R = 0.0411, wR = 0.1048 for 2888 reflections with I >2( (I). The distances between Ni and N atoms (N(1), N(2), N(3), N(4)) range from 2.050(2) to 2.140(2)?. The distances of Ni-N(5) and Ni-N(8) are 2.115(3) and 2.133(3)?, respectively. The solvent molecule H_2O(O(1)) is linked by hydrogen bonds with O(1) and N(5) and N(8) atoms. Their distances are 2.881(+x, +y, +z) and 2.893(0.5+x, y, 0.5+z)?, respectively.
文摘The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF.
基金financially supported by the Fundamental Research Funds for the Central Universities (WK2060200025)Advanced Catalysis and Green Manufacturing Collaborative Innovation Center (ACGM2016-06-01)Yixing Taodu Ying Cai Program
文摘Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane（MMAO）, were tested in the polymerization of higher α-olefin（1-hexene, 1-decene and 1-hexadecene） under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers（42-88/1000 C） with high molecular weights（Mn：（4.3-15.2） × 10^4 g·mol^-1） and narrow molecular weight distribution（Mw/Mn = 1.13-1.29, RT）, which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction.
基金Supported by the Natural Science Foundation of Zhejiang Province (Y407301)
文摘A new mixed-ligand nickel（Ⅱ） complex, [Ni（L）（DCA）（H2O）]·2H2O （L = C8H9N3, 2-aminomethyl-benzimidazole, DCA2- = 7-oxabicyclo[2,2,1]heptane-2,3-dicarboxylate, demethylcantharate, C8H8O5）, has been synthesized and characterized. The structure of the complex was determined by single-crystal X-ray diffraction. It is of monoclinic system, space group P21/c with a = 7.7211（7）, b = 12.0799（12）, c = 19.7867（19）, β = 100.390（6）°, V = 1815.2（3） nm3, Dc = 1.625 g·cm-3, Ζ = 4, F（000） = 928, R = 0.0314 and wR = 0.0822. In addition, the interaction between the complex and DNA was studied by means of fluorescence spectra and viscosity. The results indicate that the complex binds to DNA by the mode of partial intercalation with the Stern-Volmer constants Ksv of 3.81 × 104 mol·L-1.
文摘Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed.
文摘Emulsion copolymerization of styrene and ethylene catalyzed by a series of neutral nickel(Ⅱ) complexes was carried out in an aqueous system to give high-molecular-weight copolymers.The copolymers and emulsions were characterized by an array of techniques including NMR,GPC,TEM,WAXD and DSC.The results indicate that the copolymers obtained are mostly block copolymers of polyethylene with random insertion of styrene units,and their M_W is in the range of 10~5-10~6.By enhancing the electron withdrawing of the s...
文摘The title nickel complex I and cobalt complex II were obtained separately from the direct reaction of D-（＋）-leucinol with Ni（II） chloride and L-（-）-leucinol with Co（II） acetate tetra- hydrate in anhydrous methanol. The crystal structures of I and II were determined by single-crystal X-ray diffraction and further characterized by elemental analysis and IR. For I： [Ni（C18H45N3O3）]Cl2, orthorhombic, P212121, a = 11.2807（9）, b = 14.7115（11）, c = 16.3580（13） A, V = 2714.7（4） A3, Z = 4, Pcalcd = 1.177 Mg/m3, the final R = 0.0407, and 16539 reflections observed with I 〉 2σ（/）; For II： [Co（C45HI08N6015）], trigonal, R3：H, a = 23.981（3）, b =23.981（3）, c = 10.8925（15） A, γ = 120°, V = 5425.1（14） A3, Z = 3, Pcalcd = 1.002 Mg/m3, the final R = 0.0625 for 16556 observed reflections with I 〉 2σ（I）. The complexes were then used to catalyze the Henry reaction and obtained good catalytic results. The catalytic activity of the complexes was determined by IH NMR. And research is going towards the application to other organic reactions such as cyanosilylation reaction.
基金Supported by the National Natural Science Foundation of China(No.20964003)
文摘A new α-diimine ligand 1a, bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2a, {bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene}dibromo- nickel were successfully synthesized, and characterized by 1H NMR, 13C NMR, Fourier transform infrared spectroscope（FTIR）, elemental analysis and X-ray photoelectron spectroscopy（XPS）. α-Diimine ligand 1b, bis[N,N′-（2,6- dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2b, {bis[N,N′-（2,6-dimethyl- phenyl）imino]-2,3-butanediylidene}dibromonickel were also synthesized and characterized for comparison. The pre-catalyst 2a with sterically bulky, electron-donating group tert-butyl, activated by diethylaluminum chloride （DEAC） and tested in the polymerization of ethylene, was very highly active[2.01×107 g PE/（mol Ni？h？0.1 MPa）] and led to a very highly branched polyethylene（ca. 35―103 branches/1000 C）. The state of the polyethylene obtained varied from plastic, elastomer polymers to the oil-like hyperbranched polymers.
基金financially supported by PULEAD Technology Industry Co.,Ltd.,the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB36000000)the National Key Research and Development Program of China (No. 2016YFA0200904)+3 种基金the National Natural Science Foundation of China (Nos. 21771018and 21875004)the Natural Science Foundation of Beijing (No.2192018)National Natural Science Foundation of China-Regional Innovation Joint Exploration Fund (No. U19A2019)Beijing University of Chemical Technology (Start-up grant No. buctrc201901,BUCT, China)。
文摘Metal skeletons,such as Nickel Foam(NF) has attracted worldwide interests as stable host for lithium metal anode because of its high stability,large specific surface area and high conductivity.However,most metal skeletons have lithophobic surface and uneven current distribution that result in sporadic lithium nucleation and uncontrolled dendrites growth.Herein,we describe a sequential immersing strategy to generate interwoven Nickel(Ⅱ)-dimethylglyoxime(Ni-DMG) nanowires at NF to obtain composite skeleton(NDNF),which can be used as an stable host for Li metal storage.The Ni-DMG has proved effective to realize uniform lithium nucleation and dendrite-free lithium deposition.Combing with the three dimensional(3 D) hierarchical porous structure,the composite host shows a significantly improved coulombic efficiency(CE) than pristine commercial nickel foam.Moreover,the corresponding Li‖Li symmetrical cells can run more than 700 h with low voltage hysteresis 22 mV at 1.0 mA/cm^(2),and Li@NDNF‖LiFePO;full-cell exhibits a high capacity retention of 82.03% at 1.0 C during 630 cycles.These results proved the effectiveness of metal-organic complexes in governing Li metal growth and can be employed as a new strategy for dendrite-free Li metal anode and safe Li metal batteries(LMBs).
基金the National Natural Science Foundation of China(Nos.20674097,20734004)the Ministry of Education of China(Foundation for Ph.D.Training).
文摘A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precursors for ethylene polymerization in the presence of methylaluminoxane(MAO).The catalysts containing ortho-alkyl-substituents afford high molecular weight branched polyethylenes as well as a certain amount of oligomers.Enhancing the steric bulk of the alkyl substituent of the catalyst resulted in...
基金The project was supported by the Education Department of Zhejiang Province (20030710)
文摘The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 116.75(3)°, V = 1545.7(5) ?, Z = 4, Mr = 380.04, F(000) = 784, Dc = 1.633 g/cm3 and μ(MoKα) = 1.279 mm–1. The structure was refined to R = 0.0472 and wR = 0.0893 for 2571 observed reflections with I > 2σ(I). The absolute structure Flack parameter X is 0.01(2). In this crystal structure, strong face-to-face π-π stacking interactions between adjacent molecules lead to a one-dimensional chain structure.
基金supported by NNSFC (20971085)"973" Programs (2007CB209701 and 2009CB930403)the Key Project and Scientific Research Foundation for the Returned Overseas Chinese Scholars of State Education Ministry
文摘Two homochiral mercury （1） and cadmium （2） complexes derived from chiral twisted biphenyl pyridine ligand （3,3＇-bipyridine-5,5＇,6,6＇-tetramethyl-2,2＇-dimethoxy-1,1＇-biphenyl） have been synthesized and characterized by IR, microanalysis, TGA, UV-Vis, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 2. For 1, a = 14.2038（16）, b = 14.3630（17）, c = 7.0257（8）, V = 1433.3（3）3, Mr = 878.91, Dc = 2.037 g/cm3, μ = 7.549 mm-1, F（000） = 824, the final GOF = 1.017, R = 0.0296 and wR = 0.0645 for 2925 observed reflections with I 2σ（I）. For 2, a = 14.212（3）, b = 14.392（3）, c = 7.0498（14）, V = 1442.0（5）3, Mr = 790.72, Dc = 1.821 g/cm3, μ = 2.924 mm–1, F（000） = 760, the final GOF = 1.075, R = 0.0340 and wR = 0.0834 for 3144 observed reflections with I 2σ（I）. The crystal structures of 1 and 2 are isostructural and each adopts a two-dimensional supramolecular network which contains the C–H···π interactions.
基金Supported by the Scientific Research Fund of Hunan Provincial Education Department(13B029,13A030,13CY029)the Program for Excellent Talents in Hunan University of Science and Engineering(2013)+2 种基金the Construct Program of the Key Discipline in Hunan Province(2011-76)the Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province(2012-318)NSF of Hunan(11JJ2009)
文摘The reactions of chiral four-coordinated nickel（Ⅱ） complex [Ni（RR-L）]（ClO4）2/[Ni（SS- L）]（ClO4）2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni（RR-L）（β-d-HPhe）]（ClO4）2（1） and [Ni（SS-L）（β-l-HPhe）]（ClO4）2（2）, respectively（L = 5,5,7, 12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, HPhe = phenylalanine）. Single-crystal X-ray diffraction analyses revealed that the nickel（Ⅱ） atom displays a distorted octahedral coordination geometry by coordinating with four nitrogen atoms of L in a folded configuration, and two carboxylate oxygen atoms of β-d/l-HPhe in cis-position in both complexes. The monomers of [Ni（RR-L）（β-d-HPhe）]2＋ and [Ni（SS-L）（β-l-HPhe）]2＋ are connected through intermolecular hydrogen bonds to generate one-dimensional zigzag chains, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy.
基金This work was supported by the Natural Science Foundation of Guangxi Province (No. 0229004)
文摘Two coordination polymers, [ML2]n （M = Co （1）, Ni （2）, L = 3-aminobenzoic acid anion）, were synthesized by hydrothermal reaction, and their crystal structures were determined by X-ray diffraction analysis. Both compounds crystallize in monoclinic, space group P21/n with a = 8.8029（8）, b = 4.5297（4）, c = 15.2002（14）A°, β= 105.6280（10）°, C14H12CoN2O4, Mr= 331.19, Z= 2, V = 583.69（9）A°^3 Dc= 1.884 g/cm^3,μ=1.490 mm^-1, F（000） = 338, R = 0.0234 and wR = 0.0679 for 1337 observed reflections （I 〉 2σ（I）） for 1, and a = 8.7501（7）, b = 4.5191（4）, c = 15.1448（12） A°,β = 105.7730（10）° C14H12 NiN2O4, Mr = 330.97, Z = 2, V = 576.31（8）A°3, Dc = 1.907 g/cm^3,μ = 1.703 mm^-1, F（000） = 340, R = 0.0206 and wR = 0.0572 for 1209 observed reflections （I 〉 2σ（I）） for 2. In the title complexes, the M （Ⅱ） ion presents an octahedral geometry with four oxygen donors in the equatorial positions and two nitrogen donors in the axial positions. Each of the complexes has a two-dimensional network structure that is formed by the bridging of the ligand in a μ3-bridging mode via its amino and carboxyl groups.
