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Synthesis and Crystal Structure of a Bimetallic Cyanide-bridged Complex Derived from Manganese(Ⅲ) Schiff-base Complex and Pentacyanidonitrosylferrate(Ⅱ) Building Blocks
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作者 王婷婷 谢吉民 +2 位作者 夏昌坤 吴云龙 荆俊杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1265-1269,共5页
A new cyanide-bridged bimetallic assembly [Mn(3-meosalpn)(H2O)]2[Fe(CN)5NO](1) was obtained by the reaction of [Fe(CN)5NO]2-with [Mn(3-meosalpn)]+,and characterized by elemental analysis,IR and single-cry... A new cyanide-bridged bimetallic assembly [Mn(3-meosalpn)(H2O)]2[Fe(CN)5NO](1) was obtained by the reaction of [Fe(CN)5NO]2-with [Mn(3-meosalpn)]+,and characterized by elemental analysis,IR and single-crystal X-ray structure analysis.The complex crystallizes in the monoclinic system,space group P21/c with a = 12.992(5),b = 13.274(6),c = 14.644(6) ,β = 115.198(4)o,V = 2285.2(16)3,Z = 2,C43H44FeMn2N10O11,Mr = 1042.61,Dc = 1.515 g/cm3,F(000) = 1072,μ = 0.928 mm-1,S = 1.052,the final R = 0.0347 and wR = 0.0957 for 17377 observed reflections(Ⅰ 〉 2σ(Ⅰ)).X-ray single-crystal diffraction analysis reveals that 1 has a trinuclear molecular structure,in which the two [Mn(3-meosalpn)(H2O)]+ cations are linked by the central [Fe(CN)5NO]2-anion via two trans CN-groups.Furthermore,the two [Mn(3-meo-salpn)(H2O)]+ cations and [Fe(CN)5NO]2-anion are connected into a one-dimensional zigzag chain through hydrogen bonding interactions. 展开更多
关键词 manganese complex Schiff base pentacyanidonitrosylferrate(Ⅱ) crystal structure
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Lanthanum heterocyclic Schiff-base complex initiated ring-opening polymerization ofε-caprolactone
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作者 Wen Lin Wei Lin Sun Zhi Quan Shen 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1133-1136,共4页
Lanthanum complex supported by the heterocyclic Schiff-base ligand of N-(2-pyridyl)-3,5-di-tert-butyl-salicylaldimine was prepared and employed for the ring-opening polymerization(ROP)ofε-caprolactone(ε-CL).The poly... Lanthanum complex supported by the heterocyclic Schiff-base ligand of N-(2-pyridyl)-3,5-di-tert-butyl-salicylaldimine was prepared and employed for the ring-opening polymerization(ROP)ofε-caprolactone(ε-CL).The polymers obtained with this initiator showed a unimodal molecular weight distribution implied that only one active species was present.Mechanism study revealed that the polymerization proceeds via acyl-oxygen bond cleavage. 展开更多
关键词 Heterocyclic schiff-base Rare earth complex Ε-CAPROLACTONE Ring-opening polymerization
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Crystal structure and antibacterial activity of two Gd_(2)complexes based on polydentate Schiff-base ligands
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作者 ZHANG Yingyue KANG Liuqing +2 位作者 YANG Yating GUAN Xiaofen WANG Wenmin 《无机化学学报》 北大核心 2025年第9期1867-1877,共11页
Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene... Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2. 展开更多
关键词 Gd_(2)complex polydentate Schiff base crystal structure DNA INTERACTION antibacterial activity
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Density Functional Theory Study on La Complex with Schiff-base as Building Block 被引量:6
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作者 XIA Shu-Wei XU Xiang SUN Ya-Li FAN Yu-Hua BI Cai-Feng ZHANG Dong-Mei YANG Li-Rong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期197-203,共7页
Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized an... Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized and the calculation results show that the lanthanum ion is coordinated by one nitrogen atom and three oxygen atoms of L^1 and two oxygen atoms of nitrate ion. The bond length of La-N is 0.2637 nm and the average length of La-O is 0.2526 nm, which are consistent with the literatures. In addition, the stabilities, electronic structural characteristics and IR spectra of the complex have been analyzed, which describe the coordination of lanthanum ion with other atoms in detail. 展开更多
关键词 RARE-EARTH schiff-base lanthanum complex density functional theory
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Antioxidant activity of bovine serum albumin binding amino acid Schiff-bases metal complexes 被引量:2
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作者 Rong Min Wang Juan Juan Mao Jing Feng Song Cai Xia Huo Yu Feng He 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1416-1418,共3页
Glutamic acid-salicylaldehyde Schiff-base metal complexes are bound into bovine serum albumin (BSA), which afforded BSA binding Schiff-base metal complexes (BSA-SalGluM, M=Cu, Co, Ni, Zn). The BSA binding metal co... Glutamic acid-salicylaldehyde Schiff-base metal complexes are bound into bovine serum albumin (BSA), which afforded BSA binding Schiff-base metal complexes (BSA-SalGluM, M=Cu, Co, Ni, Zn). The BSA binding metal complexes were characterized by UV-vis spectra and Native PAGE. It showed that the protein structures of BSA kept after coordinating amino acid Schiff-bases metal complexes. The effect of the antioxidant activity was investigated. The results indicate that the antioxidant capacity of BSA increased more than 10 times after binding Schiff-base metal complexes. 展开更多
关键词 Natural polymer schiff-base metal complexes Glutamic acid Bovine serum albumin (BSA) Antioxidants Hydroxyl radicals
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Synthesis and Crystal Structure of a Novel Binuclear Cu(Ⅱ) Complex with Tetradentate Schiff-base Ligand 被引量:3
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作者 ZHAO Hai-Yan QIU Xiao-Hang +1 位作者 TONG Xiao-Lan SHEN Pan-Wen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1095-1099,共5页
A novel binuclear complex ([Cu^2(μ2-shed)(hshed)].(CIO4),H2O, h2shed = N-salicylidene-N'-(2-hydroxyethyl)ethylenediamine) has been synthesized and structurally characterized by X-ray diffraction analysis. ... A novel binuclear complex ([Cu^2(μ2-shed)(hshed)].(CIO4),H2O, h2shed = N-salicylidene-N'-(2-hydroxyethyl)ethylenediamine) has been synthesized and structurally characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 12.511(10), b = 15.750(12), c = 14.281 (12) A, β = 100.564(14)°, C22H31CIN4O9Cu2, Mr = 658.04, V = 2766(4) A^3, Z = 4, Dc = 1.580 g/cm^3,μ(MoKα = 1.689 mm^-1, F(000) = 1352, the final R = 0.0528 and wR = 0.1433 for 4880 independent reflections with Rint = 0.0577. The complex is a binuclear copper compound, and two Cu(Ⅱ) ions in the binuclear cation are in different coordination environments. The Cu(1) ion adopts a distorted square pyramidal geometry (x = 0.22) with four donor atoms (N2O2) of the ligand in the basal plane, and one hydroxyl oxygen atom with protonated form occupying the apical position. The Cu(2) ion assumes the geometry of a distorted square plane with four donor atoms (N2O2) of the ligand. The Cu...Cu separation is 3.103 A,. In addition, N-H…O and C-H…O intermolecular hydrogen bonding interactions link these binuclear cations into a quasi one-dimensional chain along the a axis. 展开更多
关键词 Schiff base copper (Ⅱ) complex crystal structure hydrogen bonds
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Crystal Structure of Binuclear Manganese(Ⅲ) Complex with Schiff-base Ligand,〔Mn_2(C_(22)H_(22)N_2O_2)_2(EtOH)_2 (bipy)〕(ClO_4)_2 被引量:1
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作者 冯云龙 刘世雄 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1998年第2期125-128,共4页
The title complex, [Mn2L2(EtOH)2 (bipy )](ClO4)2 (L=N,N'-ethylenebis (1-phenyl-3-imino-1-butanonato), bipy = 4, 4'-bipyridine] crystallizes inmonoclinic system, space group P21/c with a= 12. 63O(5), b=13- 151 ... The title complex, [Mn2L2(EtOH)2 (bipy )](ClO4)2 (L=N,N'-ethylenebis (1-phenyl-3-imino-1-butanonato), bipy = 4, 4'-bipyridine] crystallizes inmonoclinic system, space group P21/c with a= 12. 63O(5), b=13- 151 (2), c=18. 3773001 reflections The two [MnL(EtOH)]+ units are joined by one 4, 4'-bipyridine molecule to form a centrosymmetric binuclear complex cation [Mn2L2(EtOH)2 (bipy]2+. The coordination geometry around Mn atoms is a distorted octahe-dron with equatorial plane N2O2 from the Schiff base ligand L. 展开更多
关键词 manganese(Ⅲ) complex binuclear complex Schiff base crystal structure
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Heterogeneous degradation of toxic organic pollutants by hydrophobic copper Schiff-base complex under visible irradiation 被引量:5
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作者 SONG Quan JIA ManKe +2 位作者 MA WanHong FANG YanFen HUANG YingPing 《Science China Chemistry》 SCIE EI CAS 2013年第12期1775-1782,共8页
A hydrophobic complex of Cu2+[bis-salicylic aldehyde-o-phenylenediamine], Cu-SPA, was prepared and used as a heterogeneous photocatalyst to degrade organic pollutants in water under visible irradiation (λ≥420 nm)... A hydrophobic complex of Cu2+[bis-salicylic aldehyde-o-phenylenediamine], Cu-SPA, was prepared and used as a heterogeneous photocatalyst to degrade organic pollutants in water under visible irradiation (λ≥420 nm) at neutral pH. The structure of complex was characterized by using nuclear magnetic resonance (NMR), elemental analysis, IR and UV-vis spectrometries. Degradation of Rhodamine B (RhB), Sulforhodamine B (SRB) and Benzoic acid (BA) in water were used as model reactions to evaluate the photocatalytic activities of Cu-SPA. The results indicated that RhB and SRB were easily adsorbed on the hydrophobic surface of Cu-SPA from aqueous solution (the maximum adsorption amount: Qmax = 11.09 and 8.05 μmol/g, respectively). Under visible irradiation, RhB and SRB were decolorized completely after 210 and 240 min, respectively, and BA was removed completely after 5 h. The efficiency of H202 was 〉 95%, in contrast to that of the reaction without catalyst or light (〈 20%). In water soluble medium, the hydrophobic Cu-SPA can be used more than 6 cycles. ESR results and the behavior of cy- clic voltammetry showed that, in the reaction process, Cu2+-SPA was reduced to intermediate state Cu+-SPA firstly, which was extremely unstable and reacted rapidly with H2O2, leading to high reactive oxygen species (.OH radical ) to degrade the substrate. 展开更多
关键词 HYDROPHOBIC copper schiff-base PHOTOCATALYSIS toxic organic pollutant
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A Novel Copper(Ⅱ)Complex Based on 4-Amino-1,2,4-triazole Schiff-base:Synthesis,Crystal Structure,Spectral Characterization,and Hirshfeld Surface Analysis 被引量:1
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作者 张海洋 肖瑜 朱芸 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期848-855,共8页
A novel copper complex Cu2(L)4(1, HL = 2-ethoxy-6-([1,2,4]triazol-4-yliminomethyl)-phenol) has been synthesized and characterized by IR, single-crystal X-ray diffraction, and elemental analysis(CHN). The singl... A novel copper complex Cu2(L)4(1, HL = 2-ethoxy-6-([1,2,4]triazol-4-yliminomethyl)-phenol) has been synthesized and characterized by IR, single-crystal X-ray diffraction, and elemental analysis(CHN). The single crystal belongs to the triclinic system, space group P1 with a = 10.0991(10), b = 10.5280(12), c = 10.5777(11) A, α = 97.230(9), β = 90.640(8), γ = 92.412(9)°, Mr = 1052.05, V = 1114.6(2) A3, Z = 1, Dc = 1.567 g/cm3, F(000) = 542, μ = 1.029 mm–1, R = 0.0562 and w R = 0.1562. The fluorescence and electrochemiluminescence(ECL) of 1and HL ligand were studied. The luminescence properties of 1 can be attributed to the ligand-metal charge transfer. 展开更多
关键词 schiff-base ligand crystal structure FLUORESCENCE electrochemiluminescence Hirshfeid surfaces analysis
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Synthesis and Crystal Structure of a Cu(Ⅱ) Complex with Reduced Schiff-base N-(2-Hydroxybenzyl)-D,L-alanine and 4,4'-Bipyridine 被引量:2
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作者 郑大贵 胡久荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第6期867-871,共5页
A new complex [Cu2(sala)2(H20)2(4,4'-bipy)]'H20 (sala = N-(2-hydroxybenzyl)- D,L-alaninate, 4,4'-bipy = 4,4'-bipyridine) has been synthesized and characterized by elemental analysis, IR spectroscopy, the... A new complex [Cu2(sala)2(H20)2(4,4'-bipy)]'H20 (sala = N-(2-hydroxybenzyl)- D,L-alaninate, 4,4'-bipy = 4,4'-bipyridine) has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. The complex crystallizes in monoclinic system, space group C2/c with a = 42.44(3), b = 10.416(8), c = 15.487(13) ./k, fl = 97.455(14)°, C30H36Cu2N4O9, Mr = 723.71, V = 6789(9) A3, Dc = 1.416 g/cm3, Z = 8, F(000) = 2992, μ(MoKa) = 1.308 mm-1, R = 0.0493 and wR = 0.1004 for 4878 observed reflections (I 〉 2σ(I)). Structural analysis shows that each copper(II) atom displays a distorted square-based pyramidal coordination geometry with two oxygen atoms and one nitrogen atom from one N-(2-hydroxybenzyl)-D,L-alaninate, one nitrogen atom from 4,4'-bipyridine ligand and one water molecule. 4,4'-Bipyridine ligand bridges two Cu(II) ions to form a dinuclear compound. The molecular structure is extended into a one-dimensional wavy chain through hydrogen bonds. These 1D chains are further expanded into 2D networks through hydrogen bonds. 展开更多
关键词 copper(II) complex N-(2-hydroxybenzyl)-D L-alanine 4 4'-bipyridine crystal structure
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Steric hindrance effect of Schiff-base ligands on magnetic relaxation dynamics and emissive behavior of two dinuclear dysprosium complexes 被引量:4
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作者 Youdong Jiang Sourav Dey +5 位作者 Hongshan Ke Yongsheng Yang Lin Sun Gang Xie Sanping Chen Gopalan Rajaraman 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第7期1049-1057,I0003,共10页
The self-assembly reactions between mixed-ligand and tetrahydrate dysprosium acetate in the presence of mixed organic solvents lead to two structural similar dinuclear dysprosium complexes with composition formulas of... The self-assembly reactions between mixed-ligand and tetrahydrate dysprosium acetate in the presence of mixed organic solvents lead to two structural similar dinuclear dysprosium complexes with composition formulas of Dy_(2)(L_1)_(2)(L_(2))_(2)(CH_(3)OH)_(2)·CH_(2)Cl_(2)·CH_(3)OH(1) and Dy_(2)(L_1)_(2)(L_(3))_(2)(CH_(3)OH)_(2)·CH_(3)CN(2),where L_1,L_(2) and L_(3) represent the deprotonated form of 4-tert-butyl-2-(7-methoxybenzo[d]oxazol-2-yl)phenol,(E)-1-(((3,5-di-tert-butyI-2-hydroxyphenyI)imino)methyl)naphthalen-2-ol and(E)-2,4-di-tertbutyl-6-((2-hydroxybenzylidene)amino)phenol.The tiny difference of the core structure of 1 and 2 is derived from the steric hindrance of Schiff base ligands L_(2) and L_(3).Dynamic magnetic measurements reveal that 1 and 2 show frequency-dependent out-of-phase alternating-current susceptibility signal peaks at different temperatures under zero dc field,diagnostic of single-molecule magnet behavior.The experimental derived energy barrier to magnetization reversal for 1 and 2 is 108(1),47(2) and 33(3) K.Ab initio CASSCF calculations performed on 1 and 2 suggest that the origin of the difference in magnetic properties originates from the variation in the single-ion anisotropy that arises due to minor structural variation.Further,the equation to calculate the effective energy barrier for Dy_(2) proposed earlier is found to yield an excellent agreement with the experimental results.Solid state fluorescence measurements performed on 1 and 2 demonstrate that both exhibit two ligands centered components of fluorescent emissive,in addition,with different emitting colors and chromaticity coordinates.The discrepancy of fluorescence and single molecule magnet behavior showed by 1 and 2 can be attributed to the steric hindrance effect of Schiff base ligands. 展开更多
关键词 Fluorescent single-molecule magnets Dinuclear dysprosium complexes Mixed ligand Steric hindrance Theoretical calculations Rare earths
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Synthesis, structure, optoelectronic properties of novel zinc Schiff-base complexes
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作者 WANG LiPing JIAO ShiBo +2 位作者 ZHANG WeiFeng LIU YunQi YU Gui 《Chinese Science Bulletin》 SCIE EI CAS 2013年第22期2733-2740,共8页
Two novel zinc Schiff-base complexes, bis-(N-(2-hydroxybenzidene)-p-aminodimethylaniline)zinc(II) (2) and bis-(N-(2-hydroxy-1-naphthidene)-p-aminodimethylaniline)zinc(II) (4) were designed and synthesized. Both the co... Two novel zinc Schiff-base complexes, bis-(N-(2-hydroxybenzidene)-p-aminodimethylaniline)zinc(II) (2) and bis-(N-(2-hydroxy-1-naphthidene)-p-aminodimethylaniline)zinc(II) (4) were designed and synthesized. Both the complexes exhibit good solubility in organic solvents and excellent thermal stabilities. A single crystal of 2 was grown and its crystalline structure was determined from X-ray diffraction data. Analysis of the electronic structures of both the zinc complexes calculated by density functional theory reveals a localization of orbital. The UV-Vis absorption and photoluminescence profiles of 4 in thin film are similar to those of 2, but the emission for 4 is red-shifted compared to 2. Three-layered devices with a configuration of ITO/NPB/2/Alq 3 /LiF/Al and ITO/NPB/4/Alq 3 /LiF/Al show a yellow and red emission, respectively. 展开更多
关键词 锌络合物 晶体结构 光电特性 合成 希夫碱 席夫碱络合物 密度泛函计算 UV-VIS
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Synthesis, Crystal Structure and Nonlinear Optical Properties of Nickel(Ⅱ) Complex with Schiff-base Ligand 被引量:1
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作者 薛照明 张宣军 +3 位作者 田玉鹏 吴杰颖 蒋民华 Fun Hoong Kun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第3期265-269,共5页
The nickel(Ⅱ) complex with the new ligand of S-benzyl-b-N-[10-ethyl- phenothiazine-3-methylene]dithiocarbazate(HL) crystallizes in the triclinic system, space group P?with a = 7.516(1), b = 11.322(1), c = 13.366(1) ,... The nickel(Ⅱ) complex with the new ligand of S-benzyl-b-N-[10-ethyl- phenothiazine-3-methylene]dithiocarbazate(HL) crystallizes in the triclinic system, space group P?with a = 7.516(1), b = 11.322(1), c = 13.366(1) , a = 84.818(1), b = 81.688(1), g = 76.037(1), V = 1090.26(3) 3, Z = 1, Dc = 1.413 g/cm3, F(000) = 482, m(MoKa) = 0.774 mm-1 (l = 0.7103 ?, R = 0.0573 and wR = 0.1375 for 3357 observed reflections with I ≥ 2s(I). The HL has lost a proton from its tautomeric thiol form and acts as a single negatively charged bidentate ligand coordinating to the nickel ion via the mercapto sulfur and b-nitrogen atoms. The geometry around Ni(Ⅱ) is almost square-planar with two equivalent NiN and NiS bonds. The nonlinear absorption of HL and NiL2 solutions (in DMF) was measured by open-aperture Z-scan technique at the wavelength of 532 nm. 展开更多
关键词 crystal structure nickel complex NLO
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SVNTHESES AND CHARACTERIZATION OF TWO HIGH VALENCE VANADIUM COMPLEXES (?) SCHIFF-BASE LIGAND WITH RICH PHENOLATE OXVGEN AND THEIR CONVERSION
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作者 Jie DAI Department of Chemistry,Suzhou University,Suzhou 215006Masahiro MIKURIYA Department of Chemistry.Kuansei Gakuin University,Nishinomiya Japan 662 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第10期929-930,共2页
Two vanadium complexes of schiff base vith rich phenolate oxygen,o-(?)-salicylideneamino- methylphenol,had been synthesized and characterized.One is a V(Ⅳ)complex with an interaction via vanadyl oxygen and the other ... Two vanadium complexes of schiff base vith rich phenolate oxygen,o-(?)-salicylideneamino- methylphenol,had been synthesized and characterized.One is a V(Ⅳ)complex with an interaction via vanadyl oxygen and the other is a novel dinuclear V(V,V)complex with an oxo bridge.The conversion between the two complexes had been discussed. 展开更多
关键词 RICH IR schiff-base LIGAND WITH RICH PHENOLATE OXVGEN AND THEIR CONVERSION SVNTHESES AND CHARACTERIZATION OF TWO HIGH VALENCE VANADIUM complexES
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n-Octyloxyallene homopolymerization and random copolymerization with styrene using catalyst system composed of lanthanide Schiff-base complexes and Al(i-Bu)_(3)
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作者 JIAO JunQing ZHU WeiWei +1 位作者 NI XuFeng SHEN ZhiQuan 《Science China Chemistry》 SCIE EI CAS 2013年第7期970-976,共7页
The catalyst system composed of lanthanide Schiff-base complexes with[3,5-tBu_(2)-2-(O)C_(6)H_(2)CH=NC_(6)Hs]_(3)Ln(THF)(Ln(Salen)_(3),Ln=Sc,Y,La,Nd,Sm,Gd,Yb)and triisobutyl aluminum shows high activity for n-octyloxy... The catalyst system composed of lanthanide Schiff-base complexes with[3,5-tBu_(2)-2-(O)C_(6)H_(2)CH=NC_(6)Hs]_(3)Ln(THF)(Ln(Salen)_(3),Ln=Sc,Y,La,Nd,Sm,Gd,Yb)and triisobutyl aluminum shows high activity for n-octyloxyallene(A)homopolymerization with narrow molecular weight distribution(MWD).The influences of reaction conditions on polymerization behavior are in-vestigated,and poly(n-octyloxyallene)has a weight average molecular weight(Mw)of 20.6~10^(3) with MWD of 1.39 and 100%yield is obtained under the optimum conditions:[A1]/[Y]=50 mol/mol,[A]/[Y]=100 mol/mol,with polymerization at 80℃ for 16 h in bulk.The kinetic studies of n-octyloxyallene homopolymerization indicate that the polymerization rate is first-order with respect to the monomer concentration and shows some controlled polymerization characteristics.Random co-polymer of n-octyloxyallene with styrene is obtained by using the same binary catalyst system;the reactivity ratios of the comonomer determined by Kelen-Ttld/Ss method are rA=1.20 and r_(st)=0.35,respectively,the ratio of each segment and Mw of the resulting copolymer could be controlled by varying the feed ratio of each monomer.Determined by differential scanning calorimetry,the copolymers obtained show only one glass transition temperature,which increases gradually with the increase of styrene content in the copolymer. 展开更多
关键词 n-octyloxyallene STYRENE LANTHANIDE schiff-base coordination polymerization
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Asymmetric Cyclopropanation Catalyzed by a Copper-(Schiff-base) Complex with Double Chiral Centers
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作者 JIANG Chang sheng LI You gui +2 位作者 JIANG Chen WEN Ji wu YOU Tian pa 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期238-239,共2页
关键词 Asymmetric cyclopropanation CATALYSIS Copper-(schiff-base)
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Asymmetric Cyclopropanation Catalyzed by Four Stereoisomers of a Copper-(Schiff-base) Complex with Double Chiral Centers
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作者 Chang Sheng JIANG You Gui LI +2 位作者 Chen JIANG Fang WANG Tian Pa YOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第12期1143-1146,共4页
Four stereoisomers of a copper-(Schiff-base) complex with double chiral centers were applied to catalyze the asymmetric cyclopropanation. Two of the stereoisomers were also efficient catalysts affording high enantiom... Four stereoisomers of a copper-(Schiff-base) complex with double chiral centers were applied to catalyze the asymmetric cyclopropanation. Two of the stereoisomers were also efficient catalysts affording high enantiomeric excess of up to 91.8%. A mechanism that predicts the observed results accurately was proposed. 展开更多
关键词 Asymmetric cyclopropanation copper-(schiff-base) OLEFINS diazoacetates.
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Schiff-base Amino Alcohol-zinc Complex for Enantioselective Addition of Phenylacetylene to Aromatic Ketones
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作者 CHEN Chao HONG Liang +2 位作者 WANG Quan ZHANG Bang-zhi WANG Rui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第3期306-311,共6页
A complete study of the asymmetric addition of phenylacetylene to ketones catalyzed by Schiff-base amino alcohol-Zn complex is reported in this article. The Schiff-base amino alcohols were easily prepared from amino a... A complete study of the asymmetric addition of phenylacetylene to ketones catalyzed by Schiff-base amino alcohol-Zn complex is reported in this article. The Schiff-base amino alcohols were easily prepared from amino acids in three steps. When the amount of ligand was 1%(molar fraction), an e.e. value up to 94% was obtained. A series of practical chiral ligands were applied in the enantioselective addition of phenylacetylene to ketones without adding another stronger Lewis acid except zinc. 展开更多
关键词 Chiral tertiary alcohol Lewis acid KETONE schiff-base amino alcohol Sulfonamide alcohol Diol ligand
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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 complex dicarboxylic acid catalytic properties Knoevenagel reaction
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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