The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, ...The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.展开更多
A Ni（Ⅱ） supramolecular complex,[Ni 2 （btec）（3py） 2 （H 2 O） 8 ]（H 2 O） 4 （1）,has been synthesized by Ni（ClO 4） 2 ·6H 2 O,benzene-1,2,4,5-tetracarboxylic acid （H 4 btec） and terminal ligand 3-hydro...A Ni（Ⅱ） supramolecular complex,[Ni 2 （btec）（3py） 2 （H 2 O） 8 ]（H 2 O） 4 （1）,has been synthesized by Ni（ClO 4） 2 ·6H 2 O,benzene-1,2,4,5-tetracarboxylic acid （H 4 btec） and terminal ligand 3-hydroxypyridine （3py） in aqueous solution.The title compound crystallizes in triclinic system,space group P1,with a=8.5637（12）,b=9.4138（13）,c=10.3611（14）,α=67.9540（10）,β=85.1740（10）,γ=76.9890（10）°,V=754.33（18） 3,Z=2,M r=386.96,D c=1.704 Mg/m 3,μ=1.345 mm-1,F（000）=402,the final R=0.0222 and wR=0.0563 for 2675 observed reflections with I 2σ（Ⅰ）.The adjacent discrete molecules are further self-assembled by intermolecular π-π and O-H···O hydrogen bonding interactions to construct a 3D supramolecular framework.Magnetic measurement shows weak ferromagnetic interaction in the range of 2～300 K.展开更多
A new binuclear complex [Ni2（2,2＇-bpy）2（C8H3NO6）2（H2O）4] 1 （2,2＇-bpy = 2,2＇- bipyridine, C8H3NO6 = 4-nitrophthalate） has been synthesized by a hydrothermal reaction and characterized by X-ray single-crystal...A new binuclear complex [Ni2（2,2＇-bpy）2（C8H3NO6）2（H2O）4] 1 （2,2＇-bpy = 2,2＇- bipyridine, C8H3NO6 = 4-nitrophthalate） has been synthesized by a hydrothermal reaction and characterized by X-ray single-crystal diffraction analysis. The complex crystallizes in triclinic, space group P1 with a = 7.206（2）, b = 10.337（4）, c = 12.480（4） , α = 89.887（11）, β = 77.033（9）, γ = 78.349（6）o, V = 886.3（5） 3, Z = 1, C36H30Ni2N6O16, Mr = 920.08, Dc = 1.724 g cm-3, F（000） = 472, μ = 1.152 mm-1, the final R = 0.0458 and wR = 0.1163 for 3372 observed reflections with I 2σ（Ⅰ）. The two Ni（Ⅱ） ions are bridged by two 4-nitrophthalates both in a bis-monodentate mode. Magnetic measurements reveal that the intramolecular exchange couplings in the dimer are ferromagnetic with 2J/k = 2.32 K, D =-1.44 K and g = 2.18.展开更多
Two new Ni（ Ⅱ） coordination polymers, {[Ni（tbip）（bipy）（H2O）]-0.5H2O}n 1 and [Ni（tbip）（phen）（H2O）]n 2 （Hatbip = 5-tert-butyl isophthalic acid, bipy = 2,2＇-bipyridine, phen = 1,10-phenanthroline）, have...Two new Ni（ Ⅱ） coordination polymers, {[Ni（tbip）（bipy）（H2O）]-0.5H2O}n 1 and [Ni（tbip）（phen）（H2O）]n 2 （Hatbip = 5-tert-butyl isophthalic acid, bipy = 2,2＇-bipyridine, phen = 1,10-phenanthroline）, have been synthesized under hydrothermal conditions and characterized by elemental analysis, X-ray diffraction, and IR spectroscopy. In the two polymers, H2tbip acts as a tridentate ligand. Compound 1 has a tbip bridged 1-D linear chain which is extended by hydrogen bonds into a 1-D double chain, while compound 2 exhibits a 1-D zigzag chain.展开更多
A new kind of Schiff base HL（HL= 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-Leucine methyl ester） and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2（L′ = 1-phenyl-3-methyl-4-（p-meth...A new kind of Schiff base HL（HL= 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-Leucine methyl ester） and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2（L′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine） have been synthesized and structurally determined by X-ray diffraction. For HL： crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1： the Ni（Ⅱ） ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2： the Cu（Ⅱ） ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.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
The title complex [NiL]·H2O（C20H24N2NiO5,L = paeonol-ehylenediamine） was synthesized by the hydrothermal method and characterized by IR,cyclic voltammetry and X-ray single-crystal diffraction.The complex belong...The title complex [NiL]·H2O（C20H24N2NiO5,L = paeonol-ehylenediamine） was synthesized by the hydrothermal method and characterized by IR,cyclic voltammetry and X-ray single-crystal diffraction.The complex belongs to the monoclinic system,space group P21/c with a=13.4361（13）,b=7.3290（10）,c=20.981（2）,β=109.244°,V=1950.6（4）3,Z=4,F（000）=904,Dc=1.468 g/cm3,μ（MoKα）=1.029 mm-1,the final R=0.0588 and wR=0.1577.The complex exhibits antimicrobial activities（antimicrobial activities against Staphylococcus aureus and Escherichia codi） by agar diffusion measurement.展开更多
Three novel complexes [Cu（L1）2（H2O）2] （1）, [Ni（L1）2（H2O）2]·（H2O）4（2,HL1=5-methyl-1-（4-methylphenyl）-1,2,3-triazole-4-carboxylic acid） and [Ni2 （HL2）2（CH3OH）6]·（CH3OH）2（3,H3L2=1,2,3-tri...Three novel complexes [Cu（L1）2（H2O）2] （1）, [Ni（L1）2（H2O）2]·（H2O）4（2,HL1=5-methyl-1-（4-methylphenyl）-1,2,3-triazole-4-carboxylic acid） and [Ni2 （HL2）2（CH3OH）6]·（CH3OH）2（3,H3L2=1,2,3-triazole-4,5-dicarboxylic acid） were synthesized and characterized by elemental analysis, IR and X-ray diffraction. Complexes 1 and 2 are mononuclear structures, and are assembled into a two-dimensional sheet by C（7） H（7）···O（3） weak interactions or hydrogen-bonding interaction. Complex 3 is a centrosymmetric dinuclear structure, and is assembled into a three-dimensional supramolecular structure by hydrogen-bonding interaction.展开更多
文摘The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.
基金supported by the Natural Science Foundation of Henan Province (Nos. 092102310075 and 0511022600)
文摘A Ni（Ⅱ） supramolecular complex,[Ni 2 （btec）（3py） 2 （H 2 O） 8 ]（H 2 O） 4 （1）,has been synthesized by Ni（ClO 4） 2 ·6H 2 O,benzene-1,2,4,5-tetracarboxylic acid （H 4 btec） and terminal ligand 3-hydroxypyridine （3py） in aqueous solution.The title compound crystallizes in triclinic system,space group P1,with a=8.5637（12）,b=9.4138（13）,c=10.3611（14）,α=67.9540（10）,β=85.1740（10）,γ=76.9890（10）°,V=754.33（18） 3,Z=2,M r=386.96,D c=1.704 Mg/m 3,μ=1.345 mm-1,F（000）=402,the final R=0.0222 and wR=0.0563 for 2675 observed reflections with I 2σ（Ⅰ）.The adjacent discrete molecules are further self-assembled by intermolecular π-π and O-H···O hydrogen bonding interactions to construct a 3D supramolecular framework.Magnetic measurement shows weak ferromagnetic interaction in the range of 2～300 K.
基金supported by the Science and Technology Foundation of Guizhou Province (No.[2008]2216)
文摘A new binuclear complex [Ni2（2,2＇-bpy）2（C8H3NO6）2（H2O）4] 1 （2,2＇-bpy = 2,2＇- bipyridine, C8H3NO6 = 4-nitrophthalate） has been synthesized by a hydrothermal reaction and characterized by X-ray single-crystal diffraction analysis. The complex crystallizes in triclinic, space group P1 with a = 7.206（2）, b = 10.337（4）, c = 12.480（4） , α = 89.887（11）, β = 77.033（9）, γ = 78.349（6）o, V = 886.3（5） 3, Z = 1, C36H30Ni2N6O16, Mr = 920.08, Dc = 1.724 g cm-3, F（000） = 472, μ = 1.152 mm-1, the final R = 0.0458 and wR = 0.1163 for 3372 observed reflections with I 2σ（Ⅰ）. The two Ni（Ⅱ） ions are bridged by two 4-nitrophthalates both in a bis-monodentate mode. Magnetic measurements reveal that the intramolecular exchange couplings in the dimer are ferromagnetic with 2J/k = 2.32 K, D =-1.44 K and g = 2.18.
基金supported by the National Natural Science Foundation of China (Nos.20771026 and 20771054)the Henan Tackle Key Problem of Science and Technology (Nos.072102270030 and 072102270034)the Foundation of Education Committee of Henan Province (2006150017 and 2008A150018)
文摘Two new Ni（ Ⅱ） coordination polymers, {[Ni（tbip）（bipy）（H2O）]-0.5H2O}n 1 and [Ni（tbip）（phen）（H2O）]n 2 （Hatbip = 5-tert-butyl isophthalic acid, bipy = 2,2＇-bipyridine, phen = 1,10-phenanthroline）, have been synthesized under hydrothermal conditions and characterized by elemental analysis, X-ray diffraction, and IR spectroscopy. In the two polymers, H2tbip acts as a tridentate ligand. Compound 1 has a tbip bridged 1-D linear chain which is extended by hydrogen bonds into a 1-D double chain, while compound 2 exhibits a 1-D zigzag chain.
文摘A new kind of Schiff base HL（HL= 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-Leucine methyl ester） and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2（L′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine） have been synthesized and structurally determined by X-ray diffraction. For HL： crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1： the Ni（Ⅱ） ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2： the Cu（Ⅱ） ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.
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 National Natural Science Foundation of China(No.21973086,No.22203083)the Ministry of Science and Technology of China(No.2021YFA1200103)the Fundamental Research Funds for the Central Universities(No.WK2060000018)。
基金Supported by the Key Science Natural Fund of Jiangsu Province (No 07KJA15011)
文摘The title complex [NiL]·H2O（C20H24N2NiO5,L = paeonol-ehylenediamine） was synthesized by the hydrothermal method and characterized by IR,cyclic voltammetry and X-ray single-crystal diffraction.The complex belongs to the monoclinic system,space group P21/c with a=13.4361（13）,b=7.3290（10）,c=20.981（2）,β=109.244°,V=1950.6（4）3,Z=4,F（000）=904,Dc=1.468 g/cm3,μ（MoKα）=1.029 mm-1,the final R=0.0588 and wR=0.1577.The complex exhibits antimicrobial activities（antimicrobial activities against Staphylococcus aureus and Escherichia codi） by agar diffusion measurement.
基金Financially supported by the Natural Science Foundation of Xinjiang Province (No.2011211A009)the Open Project Program of Xinjiang Laboratory of Advanced Functional Materials (XJDX0902-2010-02)the Urumqi Science and Technology Project (No.H101133001)
文摘Three novel complexes [Cu（L1）2（H2O）2] （1）, [Ni（L1）2（H2O）2]·（H2O）4（2,HL1=5-methyl-1-（4-methylphenyl）-1,2,3-triazole-4-carboxylic acid） and [Ni2 （HL2）2（CH3OH）6]·（CH3OH）2（3,H3L2=1,2,3-triazole-4,5-dicarboxylic acid） were synthesized and characterized by elemental analysis, IR and X-ray diffraction. Complexes 1 and 2 are mononuclear structures, and are assembled into a two-dimensional sheet by C（7） H（7）···O（3） weak interactions or hydrogen-bonding interaction. Complex 3 is a centrosymmetric dinuclear structure, and is assembled into a three-dimensional supramolecular structure by hydrogen-bonding interaction.
