Diimine)nickel {[C 6 H 5 -N = C(CH 3 ) - C(CH 3 ) = N - QH 5 ]NiBr 2 }-TiCl 4 , abbreviated as NiL-TiCl 4 combined catalyst which is supported on MgCl 2 -SiO 2 carrier has been prepared, by using alkyl aluminum (AlR 3...Diimine)nickel {[C 6 H 5 -N = C(CH 3 ) - C(CH 3 ) = N - QH 5 ]NiBr 2 }-TiCl 4 , abbreviated as NiL-TiCl 4 combined catalyst which is supported on MgCl 2 -SiO 2 carrier has been prepared, by using alkyl aluminum (AlR 3 ) as the cocatalyst in place of methylaluminoxane (MAO) to catalyze ethylene oligomerization and copolymerization in situ. The influences of procedure for supporting NiL-TiCl 4 , the molar ratio of NiL to TiCl 4 , cocatalyst type and polymerization temperature on the catalytic performance were studied. The degree of branching and the composition of the branched chain of polymers produced have been investigated by IR and 13C-NMR spectra. The results show that the combined catalyst can synthesize the branched polyethylene with various banched chains .The polymerization reaction was monitored by gas chromatography and mass spectrometry (GC-MS). The results show that this catalyst promotes the oligomerization and copolymerization in situ for ethylene.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 nickel complex {Ni(2,2-bipy)(H2O)3[C8H11O2(COO)]}(H2O)3 with bicycle-[2.2.1]-2-hepten-5,6-dicarboxylic acid [C7H8(COOH)2] and 2,2'-bipyridine (bipy) as ligands has been synthesized and characterized. ...The nickel complex {Ni(2,2-bipy)(H2O)3[C8H11O2(COO)]}(H2O)3 with bicycle-[2.2.1]-2-hepten-5,6-dicarboxylic acid [C7H8(COOH)2] and 2,2'-bipyridine (bipy) as ligands has been synthesized and characterized. It crystallizes in monoclinic, space group P , with a = 0.74975(3), b = 1.20309(4), c = 1.30593(4) nm, α = 109.861(2), β = 98.519(2), γ = 90.575(2)o, V = 1.09337(7) nm3, Dc = 1.552 g/cm3, Z = 2, F(000) = 524, the final GOOF = 1.064, R = 0.0397 and wR = 0.1171. The crystal structure shows that the nickel ion is coordinated with four oxygen atoms from one bicycle[2.2.1]-2-hepten-5,6-dicarboxylic acid molecule and three water molecules and two nitrogen atoms from the 2,2′-bipyridine molecule, forming a distorted octahedral coordination geometry. The result of TG analysis shows that the title complex is stable under 200.0 ℃.展开更多
A new metal-organic coordination polymer [Ni[(2-pya)2(4,4′-bipy)]n·6nH2O (2-pya = 2-pyridinecarboxylic acid, 4,4′-bipy = 4,4′-pyridine) 1 has been hydrothermally synthesized and structurally characterize...A new metal-organic coordination polymer [Ni[(2-pya)2(4,4′-bipy)]n·6nH2O (2-pya = 2-pyridinecarboxylic acid, 4,4′-bipy = 4,4′-pyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I4 1/α with a = b = 22.5642(19), c = 10.7118(18) A, V = 5453.8(11) A^3, C22H28N4NiO10, Mr= 567.19, Dc = 1.382 g/cm^3, μ(MoKα) = 0.769 mm^-1, F(000) =2368, Z = 8, the final R = 0.0572 and wR = 0.1254 for 1401 observed reflections (I 〉 2σ(I)). It exhibits a one-dimensional chain-like structure by mixed ligands of 2-pyridinedicarboxylic acid and 4,4′-pyridine.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
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 binuclear nickel(Ⅱ) complex [Ni_2(C_7 N_4 H_5)_3(C_9 H_9 O_2)]n has been hydrothermally synthesized with nickel sulfate, 3-(pyridin-2-yl)-1H-1,2,4-triazole and 3,5-dimethylbenzoic acid(3,5-DMBA). It c...A new binuclear nickel(Ⅱ) complex [Ni_2(C_7 N_4 H_5)_3(C_9 H_9 O_2)]n has been hydrothermally synthesized with nickel sulfate, 3-(pyridin-2-yl)-1H-1,2,4-triazole and 3,5-dimethylbenzoic acid(3,5-DMBA). It crystallizes in the triclinic space group P1 with a = 11.5769(7), b = 12.3115(7), c = 12.6431(7) A, α = 81.4860(10)o, β = 64.2830(10)o, γ = 63.7130(10)o, V = 1453.45(15) A^3, D_c = 1.604 g/cm^3, Z = 2, F(000) = 720, the final GOOF = 1.048, R = 0.0285 and wR = 0.0628. The crystal structure shows that the whole molecule consists of two nickel ions bridged by three μ_2-η~1:η~0-3-(pyridin-2-yl)-1,2,4-triazole anions. The coordination environment of Ni(Ⅱ) ion is NiO_2 N_4 and NiN_5, giving a distorted octahedral geometry and square pyramidal geometry respectively. The luminescence and thermal properties of the complex were investigated.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 novel complexes, [Cd2(BMQU)2Cl4] (1) and [Ni(BMQU)2HPO4]·1.5H2O (2) (BMQU = 2-(2-benzimidazolyl)quinoline), were synthesized by the hydrothermal method and characterized by elemental analysis, IR,...Two novel complexes, [Cd2(BMQU)2Cl4] (1) and [Ni(BMQU)2HPO4]·1.5H2O (2) (BMQU = 2-(2-benzimidazolyl)quinoline), were synthesized by the hydrothermal method and characterized by elemental analysis, IR, and TG-DTG. The crystal structures were determined by single-crystal X-ray diffraction. Both 1 and 2 crystallize in the triclinic system, space group P . The data for 1: a = 0.8342(7), b = 0.9226(9), c = 1.0646(8) nm, α = 90.819(2), β = 97.466(2), γ = 98.280(2)°. The Cd(Ⅱ) is coordinated with three chlorine atoms and two nitrogen atoms of a BMQU molecule, generating a distorted square-pyramidal geometry. The dinuclear Cd(Ⅱ) complex is formed by two chlorine bridge bonds, and the one-dimensional chain structure is constructed with the hydrogen bond N-H…Cl and π-π stacking interaction. The data for 2: a = 1.2251(1), b = 1.2451(1), c = 1.2868(1) nm, α = 107.510(2), β = 98.630(1), γ = 109.921(2)°. The Ni(Ⅱ) is coordinated with four nitrogen atoms of two BMQU molecules and two oxygen atoms of a HPO42-, forming a distorted-octahedral geometry. The two-dimensional layer structure is formed by the hydrogen bonds and π-π stacking interaction between neighboring molecules. Complex 1 shows a strong blue fluorescence emission (λmax= 456 nm) at solid state.展开更多
A new oxalato-bridged dinickel(Ⅱ) complex [Ni2(NIT-MeImz)4(C2O4)](Ac)2·8H2O has been synthesized and characterized structurally as well as magnetically.It crystallizes in monoclinic,space group C2/c with...A new oxalato-bridged dinickel(Ⅱ) complex [Ni2(NIT-MeImz)4(C2O4)](Ac)2·8H2O has been synthesized and characterized structurally as well as magnetically.It crystallizes in monoclinic,space group C2/c with a=24.608(4),b=21.399(3),c=17.992(3),β=131.680(2)°,V=7076(2)3,C50H86N16Ni2O24,Mr=1412.77,Z=4,Dc=1.326 g/cm3,μ(MoKα)=0.614 mm-1,F(000)=2984,R=0.0751 and wR=0.1791 for 2956 observed reflections with Ⅰ>2σ(Ⅰ).X-ray analysis reveals that the crystal structure consists of [Ni2(NIT-MeImz)4(C2O4)]2+ moiety and two Ac^- anions. Each nickel(H) ion is six-coordinated with a distorted octahedral geometry: two nitrogen atoms and two oxygen atoms from NIT-Melmz together with two other oxygen atoms from the oxalato ion. The 2-D net structure is formed and arranged through intermolecular H-bonding interactions. Magnetic measurements show antiferromagnetic interactions for this complex.展开更多
Two novel copper complexes with methyl or trifluoro-substituted mono-β-diiminato ligands and one acetoxyl anion were synthesized and characterized by IR spectroscopy and elemental analysis for the first time. The str...Two novel copper complexes with methyl or trifluoro-substituted mono-β-diiminato ligands and one acetoxyl anion were synthesized and characterized by IR spectroscopy and elemental analysis for the first time. The structure of complex 2 bearing trifluoro substituents was further confirmed by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.377(4), b = 11.727(6), c = 12.913(7) ?, α = 116.569(6), β = 98.829(7), γ = 96.520(6)°, V = 966.2(8) ?3, Z = 2, Mr = 479.86, Dc = 1.649 g/cm3, F(000) = 482, μ = 1.205 mm-1, the final R = 0.0370 and w R = 0.0903 for 3430 observed reflections with I 〉 2σ(I). These mono-β-diiminato copper complexes can effectively catalyze methacrylate(MA) polymerization when activated by MMAO. The introduction of fluoro groups into the N-aryl ring of β-diiminato ligands can greatly increase the catalytic activity of copper complexes as well as the molecular weight of PMA.展开更多
A new nickel(Ⅱ) complex Ni2(L)2(2,2'-bipy)2·5.5H2O with methy-bicycle[2.2.1]hept-5-ene-2,3-dicarboxylic acid(H2L) and 2,2?-bipyridine(2,2'-bipy) as ligands has been synthesized in the mixed solvent ...A new nickel(Ⅱ) complex Ni2(L)2(2,2'-bipy)2·5.5H2O with methy-bicycle[2.2.1]hept-5-ene-2,3-dicarboxylic acid(H2L) and 2,2?-bipyridine(2,2'-bipy) as ligands has been synthesized in the mixed solvent DMF and water(v:v = 5:2). It crystallizes in the triclinic space group P1 with a = 10.414(2), b = 12.884(3), c = 16.176(4) A, α = 70.715(5), β = 80.599(5), γ = 77.383(6)°, V = 1989.4(8) A^3, Dc = 1.531 g/cm^3, Z = 2, F(000) = 958, GOOF = 1.028, the final R = 0.0808 and w R = 0.2036. The crystal structure shows that the whole molecule consists of two independent dinuclear units, in which two nickel ions are bridged by two μ2-η1:η0 3-carboxylate groups of L2- anions. The coordination environment of Ni(Ⅱ) ion is Ni N2O3, giving a distorted square pyramidal geometry. The thermal stability and electrochemical properties of the complex were investigated.展开更多
α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were ...α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were designed and synthesized for olefin polymerization.In this work,we synthesized a series of asymmetricα-diimide nickel complexes with different steric hindrances and used them for ethylene polymerization.These nickel catalysts have high ethylene polymerization activity,up to 6.51×10^(6)g·mol^(−1)·h^(−1),and the prepared polyethylene has a moderate melting point and high molecular weight(up to 38.2×10^(4)g·mol^(−1)),with a branching density distribution between 7 and 94 branches per 1000 carbons.More importantly,the polyethylene prepared by these catalysts exhibits excellent tensile properties,with strain and stress reaching 800%and 30 MPa,respectively.展开更多
Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmeth...Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.展开更多
Two new manganese(Ⅱ ) trinuclear complexes and two new nickel (Ⅱ) trinuclear compIexes, namely, [Mn3 (BZT ) (Phen )6] (ClO4 )3 (complex 1 ), [Mn (BZT)· (Nphen )6] (ClO4 )3 (complex 2), [Ni3 (BZT) (Phen)6] (ClO4...Two new manganese(Ⅱ ) trinuclear complexes and two new nickel (Ⅱ) trinuclear compIexes, namely, [Mn3 (BZT ) (Phen )6] (ClO4 )3 (complex 1 ), [Mn (BZT)· (Nphen )6] (ClO4 )3 (complex 2), [Ni3 (BZT) (Phen)6] (ClO4 )3· 5H2O (complex3) and [Ni3 (BZT ) (Nphen )6] (ClO4 )3 (complex 4 ) (BZT = 1, 3, 5-benzenetricarboxylato, Phen = 1, 10-phenthroline, Nphen = 5-nitro-1, 10-phenanthroline )have been synthesized. The complexes were characterized using elemental analysis,IR and electronic reflection spectra. These complexes are proposed to have extended 1, 3, 5-benzenetricarboxylato-bridged structure and to consist of three manganese (Ⅱ) or three nickel(Ⅱ). The X-band ESR spectra of the complex 1 and complex 2were recorded at room temperature. The variable-temperature magnetic susceptibilities of complex 1 and complex 3 were measured over 4. 2-300 K. According to experimental results of the variable-temperature magnetic susceptibility, the magnetic interaction between the paramagnetic centers is too weak to be detected using the usual magnetic susceptibility technique.展开更多
Two complexes with formulas [Ni L][(Ni L)(IPA)2]·8H2O(1) and [(Ni L)(H2O)2] [(Ni L)(PMA)]·4H2O(2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane,IPA2– = isophthalic anion,P...Two complexes with formulas [Ni L][(Ni L)(IPA)2]·8H2O(1) and [(Ni L)(H2O)2] [(Ni L)(PMA)]·4H2O(2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane,IPA2– = isophthalic anion,PMA4– = 1,2,4,5-benzenetetracarboxylic anion) were synthesized and characterized by elemental analyses and IR spectra.The crystal structures were determined by X-ray diffraction.In complex 1,the [Ni L]^2+ bridged IPA^2– to give [(Ni L)(IPA)2]^2– monomer,and the [Ni L]^2+ bridged PMA4– to form a one-dimensional chain [(Ni L)(PMA)]n^2n– in complex 2.The [Ni L]^2+ and [(Ni L)(IPA)2]^2–/[(Ni L)(PMA)]^2– are connected through intermolecular hydrogen bonding to generate three-dimensional supramolecular structures.展开更多
Reactions of NiCl2-6H2O with dmpzm and formic or acetic acid at PH = 7 produced the two title compounds, [Ni(dmpzm)2(HCO2)]Cl·2H2O 1 and [Ni(dmpzm)2(OAc)]C2·H2O 2 (dmpzm = 1,1 '-methylenebis(3,5-d...Reactions of NiCl2-6H2O with dmpzm and formic or acetic acid at PH = 7 produced the two title compounds, [Ni(dmpzm)2(HCO2)]Cl·2H2O 1 and [Ni(dmpzm)2(OAc)]C2·H2O 2 (dmpzm = 1,1 '-methylenebis(3,5-dimethyl-lH-pyrazole)). 1 and 2 were characterized by elemental analysis, IR spectra, and thermogravimetric analysis. 1 crystallizes in the orthorhombic system, space group Pcca with a = 18.700(2), b = 8.6843(9), c = 18.098(2)A, V= 2939.1(5)A^3, Z = 4, Dc = 1.319 g/cm^3, T = 193 K, C23H37CINsNiO4, Mr = 583.75, F(000) = 1232, p(MoKa) = 0.792 cm^-1, S = 1.079, R = 0.0772 and wR = 0.1958 for 2265 observed reflections with I〉 2σ(I). 2 crystallizes in the orthorhombic system, space group Pcca with a = 17.011(3), b = 18.630(4), c = 19.300(4)A, V = 6117(2)A^3, Z = 8, Dc = 1.337 g/cm^3, T= 193(2) K, C24H41C1N8NiO5, Mr = 615.79, F(000) = 2608, μ(MoKa) = 0.768 cm^-1, S = 1.059, R = 0.0518 and wR = 0.1109 for 5124 observed reflections with I 〉 2σ(I). The Ni atoms in 1 or 2 are chelated by two dmpzm ligands and one formate or acetate anion, forming slightly distorted octahedral geometries. In the crystals of 1 or 2, intermolecular hydrogen bonding interactions result in the formation of 2D hydrogen-bonded frameworks.展开更多
In the ethanol solvent, a nickel(Ⅱ) complex Ni(C12H10N2O2S)2 upon reaction of 2'-(2-thienylidene)-hydroxybenzoylhydrazide with nickel acetate was synthesized, and its structure was characterized by IR, UV, ele...In the ethanol solvent, a nickel(Ⅱ) complex Ni(C12H10N2O2S)2 upon reaction of 2'-(2-thienylidene)-hydroxybenzoylhydrazide with nickel acetate was synthesized, and its structure was characterized by IR, UV, elemental analysis and X-ray diffraction analysis. The crystal belongs to monoclinic system, space group C2/c with a = 22.052(3), b = 5.9681(6), c = 18.522(2)A , β = 110.679(4)°, V = 2280.6(4)A^3, Z = 4, Mr = 551.27, μ = 1.606 mm^-1, Dc = 1.075 g/cm^3, F(000) = 1136 and Rint = 0.0556. The nickel(Ⅱ ) atom in the compound is four-coordinated with two nitrogen atoms from amide and two oxygen atoms from keto group. The biological activities have been measured, show- ing the compound exhibits better anti-bacterial activity than the ligand.展开更多
基金This project was supported by the National Natural Science Foundation of China (No. 29874039) and the Foundation ofGuangdong Province (No. 031598).
文摘Diimine)nickel {[C 6 H 5 -N = C(CH 3 ) - C(CH 3 ) = N - QH 5 ]NiBr 2 }-TiCl 4 , abbreviated as NiL-TiCl 4 combined catalyst which is supported on MgCl 2 -SiO 2 carrier has been prepared, by using alkyl aluminum (AlR 3 ) as the cocatalyst in place of methylaluminoxane (MAO) to catalyze ethylene oligomerization and copolymerization in situ. The influences of procedure for supporting NiL-TiCl 4 , the molar ratio of NiL to TiCl 4 , cocatalyst type and polymerization temperature on the catalytic performance were studied. The degree of branching and the composition of the branched chain of polymers produced have been investigated by IR and 13C-NMR spectra. The results show that the combined catalyst can synthesize the branched polyethylene with various banched chains .The polymerization reaction was monitored by gas chromatography and mass spectrometry (GC-MS). The results show that this catalyst promotes the oligomerization and copolymerization in situ for ethylene.
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.
基金Project supported by the Fund of Hunan Provincial Natural Science Foundation of China (No.11JJ9006)the Fund of Science and Technology Committee of Hunan Province (2009FJ3031)
文摘The nickel complex {Ni(2,2-bipy)(H2O)3[C8H11O2(COO)]}(H2O)3 with bicycle-[2.2.1]-2-hepten-5,6-dicarboxylic acid [C7H8(COOH)2] and 2,2'-bipyridine (bipy) as ligands has been synthesized and characterized. It crystallizes in monoclinic, space group P , with a = 0.74975(3), b = 1.20309(4), c = 1.30593(4) nm, α = 109.861(2), β = 98.519(2), γ = 90.575(2)o, V = 1.09337(7) nm3, Dc = 1.552 g/cm3, Z = 2, F(000) = 524, the final GOOF = 1.064, R = 0.0397 and wR = 0.1171. The crystal structure shows that the nickel ion is coordinated with four oxygen atoms from one bicycle[2.2.1]-2-hepten-5,6-dicarboxylic acid molecule and three water molecules and two nitrogen atoms from the 2,2′-bipyridine molecule, forming a distorted octahedral coordination geometry. The result of TG analysis shows that the title complex is stable under 200.0 ℃.
基金Supported by the Science and Technology Research Projects of the Education Office of Jilin Province (No. 2007. 213)
文摘A new metal-organic coordination polymer [Ni[(2-pya)2(4,4′-bipy)]n·6nH2O (2-pya = 2-pyridinecarboxylic acid, 4,4′-bipy = 4,4′-pyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I4 1/α with a = b = 22.5642(19), c = 10.7118(18) A, V = 5453.8(11) A^3, C22H28N4NiO10, Mr= 567.19, Dc = 1.382 g/cm^3, μ(MoKα) = 0.769 mm^-1, F(000) =2368, Z = 8, the final R = 0.0572 and wR = 0.1254 for 1401 observed reflections (I 〉 2σ(I)). It exhibits a one-dimensional chain-like structure by mixed ligands of 2-pyridinedicarboxylic acid and 4,4′-pyridine.
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 Scientific Research Found of Hunan Provincial Education Department of China(17A049,17C0226)Industry and Research Key Project of Hengyang City(2017KJ155,2017KJ193)Doctoral Scientific Research Foundation of Hengyang Normal University(17D01)
文摘A new binuclear nickel(Ⅱ) complex [Ni_2(C_7 N_4 H_5)_3(C_9 H_9 O_2)]n has been hydrothermally synthesized with nickel sulfate, 3-(pyridin-2-yl)-1H-1,2,4-triazole and 3,5-dimethylbenzoic acid(3,5-DMBA). It crystallizes in the triclinic space group P1 with a = 11.5769(7), b = 12.3115(7), c = 12.6431(7) A, α = 81.4860(10)o, β = 64.2830(10)o, γ = 63.7130(10)o, V = 1453.45(15) A^3, D_c = 1.604 g/cm^3, Z = 2, F(000) = 720, the final GOOF = 1.048, R = 0.0285 and wR = 0.0628. The crystal structure shows that the whole molecule consists of two nickel ions bridged by three μ_2-η~1:η~0-3-(pyridin-2-yl)-1,2,4-triazole anions. The coordination environment of Ni(Ⅱ) ion is NiO_2 N_4 and NiN_5, giving a distorted octahedral geometry and square pyramidal geometry respectively. The luminescence and thermal properties of the complex were investigated.
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Supported by the Natural Science Foundation of Education Department of Henan Province (No. 2011B150025)
文摘Two novel complexes, [Cd2(BMQU)2Cl4] (1) and [Ni(BMQU)2HPO4]·1.5H2O (2) (BMQU = 2-(2-benzimidazolyl)quinoline), were synthesized by the hydrothermal method and characterized by elemental analysis, IR, and TG-DTG. The crystal structures were determined by single-crystal X-ray diffraction. Both 1 and 2 crystallize in the triclinic system, space group P . The data for 1: a = 0.8342(7), b = 0.9226(9), c = 1.0646(8) nm, α = 90.819(2), β = 97.466(2), γ = 98.280(2)°. The Cd(Ⅱ) is coordinated with three chlorine atoms and two nitrogen atoms of a BMQU molecule, generating a distorted square-pyramidal geometry. The dinuclear Cd(Ⅱ) complex is formed by two chlorine bridge bonds, and the one-dimensional chain structure is constructed with the hydrogen bond N-H…Cl and π-π stacking interaction. The data for 2: a = 1.2251(1), b = 1.2451(1), c = 1.2868(1) nm, α = 107.510(2), β = 98.630(1), γ = 109.921(2)°. The Ni(Ⅱ) is coordinated with four nitrogen atoms of two BMQU molecules and two oxygen atoms of a HPO42-, forming a distorted-octahedral geometry. The two-dimensional layer structure is formed by the hydrogen bonds and π-π stacking interaction between neighboring molecules. Complex 1 shows a strong blue fluorescence emission (λmax= 456 nm) at solid state.
基金supported by the National Natural Science Foundation of China (Nos 20471026 and 20771054)the Natural Science Foundation of Henan Province (No 0311021200)
文摘A new oxalato-bridged dinickel(Ⅱ) complex [Ni2(NIT-MeImz)4(C2O4)](Ac)2·8H2O has been synthesized and characterized structurally as well as magnetically.It crystallizes in monoclinic,space group C2/c with a=24.608(4),b=21.399(3),c=17.992(3),β=131.680(2)°,V=7076(2)3,C50H86N16Ni2O24,Mr=1412.77,Z=4,Dc=1.326 g/cm3,μ(MoKα)=0.614 mm-1,F(000)=2984,R=0.0751 and wR=0.1791 for 2956 observed reflections with Ⅰ>2σ(Ⅰ).X-ray analysis reveals that the crystal structure consists of [Ni2(NIT-MeImz)4(C2O4)]2+ moiety and two Ac^- anions. Each nickel(H) ion is six-coordinated with a distorted octahedral geometry: two nitrogen atoms and two oxygen atoms from NIT-Melmz together with two other oxygen atoms from the oxalato ion. The 2-D net structure is formed and arranged through intermolecular H-bonding interactions. Magnetic measurements show antiferromagnetic interactions for this complex.
基金Supported by the National Natural Science Foundation of China(21172269)the Applied Fundamental Research Project of Wuhan City(2015011701011598)
文摘Two novel copper complexes with methyl or trifluoro-substituted mono-β-diiminato ligands and one acetoxyl anion were synthesized and characterized by IR spectroscopy and elemental analysis for the first time. The structure of complex 2 bearing trifluoro substituents was further confirmed by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.377(4), b = 11.727(6), c = 12.913(7) ?, α = 116.569(6), β = 98.829(7), γ = 96.520(6)°, V = 966.2(8) ?3, Z = 2, Mr = 479.86, Dc = 1.649 g/cm3, F(000) = 482, μ = 1.205 mm-1, the final R = 0.0370 and w R = 0.0903 for 3430 observed reflections with I 〉 2σ(I). These mono-β-diiminato copper complexes can effectively catalyze methacrylate(MA) polymerization when activated by MMAO. The introduction of fluoro groups into the N-aryl ring of β-diiminato ligands can greatly increase the catalytic activity of copper complexes as well as the molecular weight of PMA.
基金Supported by the Construct Program of the Key Discipline in Hunan ProvinceKey Project of Industrial Science and Technology Support of Hengyang City(2015KG23)
文摘A new nickel(Ⅱ) complex Ni2(L)2(2,2'-bipy)2·5.5H2O with methy-bicycle[2.2.1]hept-5-ene-2,3-dicarboxylic acid(H2L) and 2,2?-bipyridine(2,2'-bipy) as ligands has been synthesized in the mixed solvent DMF and water(v:v = 5:2). It crystallizes in the triclinic space group P1 with a = 10.414(2), b = 12.884(3), c = 16.176(4) A, α = 70.715(5), β = 80.599(5), γ = 77.383(6)°, V = 1989.4(8) A^3, Dc = 1.531 g/cm^3, Z = 2, F(000) = 958, GOOF = 1.028, the final R = 0.0808 and w R = 0.2036. The crystal structure shows that the whole molecule consists of two independent dinuclear units, in which two nickel ions are bridged by two μ2-η1:η0 3-carboxylate groups of L2- anions. The coordination environment of Ni(Ⅱ) ion is Ni N2O3, giving a distorted square pyramidal geometry. The thermal stability and electrochemical properties of the complex were investigated.
基金supported by the National Natural Science Foundation of China(52203016)the USTC Research Funds of the Double First-Class Initiative(YD9990002018)+3 种基金the Overseas Students Innovation and Entrepreneurship Support Program Project of Anhui Province(2021LCX022)the Key R&D Projects in Anhui Province(2022i01020012)the Natural Science Foundation of Hefei(2022039)the Excellent Research and Innovation Team Project of Anhui Province(2022AH010001).
文摘α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were designed and synthesized for olefin polymerization.In this work,we synthesized a series of asymmetricα-diimide nickel complexes with different steric hindrances and used them for ethylene polymerization.These nickel catalysts have high ethylene polymerization activity,up to 6.51×10^(6)g·mol^(−1)·h^(−1),and the prepared polyethylene has a moderate melting point and high molecular weight(up to 38.2×10^(4)g·mol^(−1)),with a branching density distribution between 7 and 94 branches per 1000 carbons.More importantly,the polyethylene prepared by these catalysts exhibits excellent tensile properties,with strain and stress reaching 800%and 30 MPa,respectively.
文摘Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.
文摘Two new manganese(Ⅱ ) trinuclear complexes and two new nickel (Ⅱ) trinuclear compIexes, namely, [Mn3 (BZT ) (Phen )6] (ClO4 )3 (complex 1 ), [Mn (BZT)· (Nphen )6] (ClO4 )3 (complex 2), [Ni3 (BZT) (Phen)6] (ClO4 )3· 5H2O (complex3) and [Ni3 (BZT ) (Nphen )6] (ClO4 )3 (complex 4 ) (BZT = 1, 3, 5-benzenetricarboxylato, Phen = 1, 10-phenthroline, Nphen = 5-nitro-1, 10-phenanthroline )have been synthesized. The complexes were characterized using elemental analysis,IR and electronic reflection spectra. These complexes are proposed to have extended 1, 3, 5-benzenetricarboxylato-bridged structure and to consist of three manganese (Ⅱ) or three nickel(Ⅱ). The X-band ESR spectra of the complex 1 and complex 2were recorded at room temperature. The variable-temperature magnetic susceptibilities of complex 1 and complex 3 were measured over 4. 2-300 K. According to experimental results of the variable-temperature magnetic susceptibility, the magnetic interaction between the paramagnetic centers is too weak to be detected using the usual magnetic susceptibility technique.
基金supported by the Natural Science Foundation of Hunan Province(2015JJ2072)the Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South(XNZW14C08)+1 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)
文摘Two complexes with formulas [Ni L][(Ni L)(IPA)2]·8H2O(1) and [(Ni L)(H2O)2] [(Ni L)(PMA)]·4H2O(2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane,IPA2– = isophthalic anion,PMA4– = 1,2,4,5-benzenetetracarboxylic anion) were synthesized and characterized by elemental analyses and IR spectra.The crystal structures were determined by X-ray diffraction.In complex 1,the [Ni L]^2+ bridged IPA^2– to give [(Ni L)(IPA)2]^2– monomer,and the [Ni L]^2+ bridged PMA4– to form a one-dimensional chain [(Ni L)(PMA)]n^2n– in complex 2.The [Ni L]^2+ and [(Ni L)(IPA)2]^2–/[(Ni L)(PMA)]^2– are connected through intermolecular hydrogen bonding to generate three-dimensional supramolecular structures.
基金The project was supported by the NSF of Jiangsu Province (No. BK2004205)the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20050285004)
文摘Reactions of NiCl2-6H2O with dmpzm and formic or acetic acid at PH = 7 produced the two title compounds, [Ni(dmpzm)2(HCO2)]Cl·2H2O 1 and [Ni(dmpzm)2(OAc)]C2·H2O 2 (dmpzm = 1,1 '-methylenebis(3,5-dimethyl-lH-pyrazole)). 1 and 2 were characterized by elemental analysis, IR spectra, and thermogravimetric analysis. 1 crystallizes in the orthorhombic system, space group Pcca with a = 18.700(2), b = 8.6843(9), c = 18.098(2)A, V= 2939.1(5)A^3, Z = 4, Dc = 1.319 g/cm^3, T = 193 K, C23H37CINsNiO4, Mr = 583.75, F(000) = 1232, p(MoKa) = 0.792 cm^-1, S = 1.079, R = 0.0772 and wR = 0.1958 for 2265 observed reflections with I〉 2σ(I). 2 crystallizes in the orthorhombic system, space group Pcca with a = 17.011(3), b = 18.630(4), c = 19.300(4)A, V = 6117(2)A^3, Z = 8, Dc = 1.337 g/cm^3, T= 193(2) K, C24H41C1N8NiO5, Mr = 615.79, F(000) = 2608, μ(MoKa) = 0.768 cm^-1, S = 1.059, R = 0.0518 and wR = 0.1109 for 5124 observed reflections with I 〉 2σ(I). The Ni atoms in 1 or 2 are chelated by two dmpzm ligands and one formate or acetate anion, forming slightly distorted octahedral geometries. In the crystals of 1 or 2, intermolecular hydrogen bonding interactions result in the formation of 2D hydrogen-bonded frameworks.
基金Supported by the Natural Science Foundation of Zhejiang Province (No. Y406049)Scientific Research Fund of Zhejiang Provincial Education Department (No. 20060079)
文摘In the ethanol solvent, a nickel(Ⅱ) complex Ni(C12H10N2O2S)2 upon reaction of 2'-(2-thienylidene)-hydroxybenzoylhydrazide with nickel acetate was synthesized, and its structure was characterized by IR, UV, elemental analysis and X-ray diffraction analysis. The crystal belongs to monoclinic system, space group C2/c with a = 22.052(3), b = 5.9681(6), c = 18.522(2)A , β = 110.679(4)°, V = 2280.6(4)A^3, Z = 4, Mr = 551.27, μ = 1.606 mm^-1, Dc = 1.075 g/cm^3, F(000) = 1136 and Rint = 0.0556. The nickel(Ⅱ ) atom in the compound is four-coordinated with two nitrogen atoms from amide and two oxygen atoms from keto group. The biological activities have been measured, show- ing the compound exhibits better anti-bacterial activity than the ligand.