期刊文献+
共找到819篇文章
< 1 2 41 >
每页显示 20 50 100
Structures and magnetism of dinuclear Co complexes based on imine derivatives
1
作者 SUN Yadan LI Xinfeng +2 位作者 LIU Qiang Hiroki Oshio MENG Yinshan 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2212-2220,共9页
This study presents the synthesis of three dinuclear cobalt complexes based on three imine derivatives:bis-[4-(2-pyridylmethyleneamino)-phenyl]thioether(L1),bis-[4-(2-pyridylmethyleneamino)-phenyl]ether(L2),and bis-[4... This study presents the synthesis of three dinuclear cobalt complexes based on three imine derivatives:bis-[4-(2-pyridylmethyleneamino)-phenyl]thioether(L1),bis-[4-(2-pyridylmethyleneamino)-phenyl]ether(L2),and bis-[4-(2-pyridylmethyleneamino)-phenyl]methane(L3).Single-crystal X-ray diffraction analysis reveals that the complexes[Co_(2)(L1)3](ClO_(4))4·2CH_(3)CN(1),[Co_(2)(L2)3](ClO_(4))4·2CH_(3)OH(2),and[Co_(2)(L3)3](ClO_(4))4·2CH_(3)OH(3)all exhibit a dinuclear structure.Magnetic test results show that complex 3 exhibited irreversible SCO behavior induced by loss of solvent at 300 K,with the average Co-N bond length increasing from 0.2139(3)to 0.2153(3)nm.Meanwhile,the desolvated complex 3 exhibited paramagnetic behavior similar to that of complexes 1 and 2.Variable-temperature UV-Vis spectroscopic studies also indicate that complex 3 undergoes a solvent-loss-induced spin-state transition.CCDC:2347354,1(120 K);2347355,2(120 K);2347356,3(120 K);2347357,3(400 K). 展开更多
关键词 spin crossover dinuclear cobalt complex imine derivatives
下载PDF
Cobalt Schiff base complexes: Synthesis characterization and catalytic application in Suzuki–Miyaura reaction 被引量:1
2
作者 Rasheeda M.Ansari Lolakshi K.Mahesh Badekai Ramachandra Bhat 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第3期556-563,共8页
3-Methoxysalicylaldehyde was condensed with the amines 4-aminoacetophenone and 2-amino-5-bromopyridine to obtain Schiff base ligands, 1 and 2, which were coordinated to cobalt salts as complex 1 and complex 2, respect... 3-Methoxysalicylaldehyde was condensed with the amines 4-aminoacetophenone and 2-amino-5-bromopyridine to obtain Schiff base ligands, 1 and 2, which were coordinated to cobalt salts as complex 1 and complex 2, respectively. The synthesized ligands and complexes were characterized by spectroscopic(FT-IR,UV–Vis,~1H-NMR and mass spectrometry), thermal(TGA) and elemental analysis. The structures of the complexes were verified by evaluating their magnetic susceptibility and spectroscopic evidences. Synthesized complexes were studied for their catalytic activity in the Suzuki–Miyaura cross-coupling of aryl halides with phenylboronic acid. Optimized reaction yields 90% of the cyanobiphenyl for complex 1 and 91% for complex 2 with 0.1 mmol of catalyst loading thereby substantiating the C\\C coupling efficiency of the synthesized complexes, 1 and 2. 展开更多
关键词 Transition metal complex Schiff base Suzuki-Miyaura coupling reaction cobalt
下载PDF
Novel cobalt(Ⅱ) complexes of amino acids-Schiff bases catalyzed aerobic oxidation of various alcohols to ketones and aldehyde 被引量:13
3
作者 Seyed Mohammad Seyedi Reza Sandaroos Gholam Hossein Zohuri 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第11期1303-1306,共4页
Two cobalt(Ⅱ) complexes 1 and 2 of Schiff bases derived from amino acids were synthesized and used for oxidation of benzyl alcohol with molecular oxygen at different conditions of pH,solvent,temperature and complex... Two cobalt(Ⅱ) complexes 1 and 2 of Schiff bases derived from amino acids were synthesized and used for oxidation of benzyl alcohol with molecular oxygen at different conditions of pH,solvent,temperature and complex/alcohol molar ratio to optimize reaction conditions and to evaluate the catalytic efficiency of new cobalt Schiff base complexes.Under obtained optimum conditions,various alcohols were oxidized to corresponding aldehydes and ketones. 展开更多
关键词 cobalt(Ⅱ) complexes Alcohol oxidation Aerobic oxidation
下载PDF
Synthesis and Catalytic Activity of Nickel(Ⅱ)and Cobalt(Ⅱ) Complexes Involving Chiral Leucinol 被引量:2
4
作者 罗梅 张志军 +1 位作者 汪磊 张竟成 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第12期1851-1856,共6页
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
关键词 chiral ieucinol nickel complex cobalt complex Ni(II) chloride Co(II) acetate tetrahydrate
下载PDF
Hydrothermal Syntheses and Crystal Structures of Cobalt(Ⅱ) Complexes Constructed by Dipyrido[3,2-a:2',3'-c]phenazine and Different Carboxylate Ligands 被引量:3
5
作者 李秀颖 王珊珊 +3 位作者 刘春波 刘玲 王苗苗 车广波 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第12期1803-1809,共7页
Two new metal-organic complexes,{[Co2(bptc)(DPPZ)2(H2O)2]·H2O}n 1 and {[Co2(ccm)2(DPPZ)2]·2H2O}n 2,were obtained by the hydrothermal reactions of Co(NO3)2·6H2O with chelating ligand dipyrido... Two new metal-organic complexes,{[Co2(bptc)(DPPZ)2(H2O)2]·H2O}n 1 and {[Co2(ccm)2(DPPZ)2]·2H2O}n 2,were obtained by the hydrothermal reactions of Co(NO3)2·6H2O with chelating ligand dipyrido[3,2-a:2',3'-c]phenazine(DPPZ) and the corresponding carboxylic acid,namely,3,3',4,4'-benzophenonetetracarboxylic acid(H4bptc) or 2-carboxycinnamic acid(H2ccm),respectively.The complexes were structurally characterized by single-crystal X-ray diffraction,elemental analyses,IR spectra,and thermal gravimetry.1 presents unique chiral chain structures,which are further consolidated into three-dimensional supramolecular frameworks via noncovalent bonds,such as hydrogen bonding and π-π interactions.2 features infinite double-chain structures,which are connected by strong π-π interactions to result in three-dimensional supramolecular architectures. 展开更多
关键词 cobalt(Ⅱ) complex dipyrido[3 2-a:2' 3'-c]phenazine crystal structure
下载PDF
Syntheses,Crystal Structures,and Magnetic Properties of Cobalt(Ⅱ) Complexes with 1,1-Cyclohexanediacetic Acid 被引量:5
6
作者 鞠丰阳 李云平 +1 位作者 李桂连 刘广臻 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期404-412,共9页
Two new Co(Ⅱ) coordination polymers,{[Co_3(Hchda)_2(chda)_2(bpp)_2(H_2O)_2]}_n 1 and {[Co(chda)(bpe)(H_2O)]·3H_2O}_n 2(H_2chda = 1,1-cyclohexanediacetic acid,bpp = 1,3-bis(4-pyridinyl)propane ... Two new Co(Ⅱ) coordination polymers,{[Co_3(Hchda)_2(chda)_2(bpp)_2(H_2O)_2]}_n 1 and {[Co(chda)(bpe)(H_2O)]·3H_2O}_n 2(H_2chda = 1,1-cyclohexanediacetic acid,bpp = 1,3-bis(4-pyridinyl)propane and bpe = 1,2-bis(4-pyridinyl)ethylene),were hydrothermally synthesized and then characterized by elemental analysis,IR spectroscopy,thermogravimetric analysis(TGA),and single-crystal X-ray diffraction.Complex 1 possesses an infinite metal-organic layer based on triply bridged linear trinuclear subunits and complex 2 exhibits a square(4,4) grid layer with dangling lateral arms resulting from eight-membered rings above and below the layer.In addition,magnetic properties of complexes 1 and 2 are also given. 展开更多
关键词 1 1-cyclohexanediacetic acid hydrothermal synthesis cobalt(Ⅱ) complex magnetic properties
下载PDF
Molecular and Supramolecular Structures of Manganese(Ⅱ) and Cobalt(Ⅱ) Complexes with 1-Carboxymethylpyridinium-4-carboxylate 被引量:1
7
作者 王艳琴 高恩庆 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第9期1331-1336,共6页
Two complexes with a zwitterionic dicarboxylate ligand,Mn(L)2(H2O)4 1 and Co(L)2(H2O)4 2(L = 1-carboxymethylpyridinium-4-carboxylate),were synthesized and structurally characterized.Complex 1 crystallizes in... Two complexes with a zwitterionic dicarboxylate ligand,Mn(L)2(H2O)4 1 and Co(L)2(H2O)4 2(L = 1-carboxymethylpyridinium-4-carboxylate),were synthesized and structurally characterized.Complex 1 crystallizes in monoclinic,space group P21 with a = 6.490(2),b = 19.210(7),c = 7.813(3) ,β = 92.716(5)o,V = 972.9(6) 3,Z = 2,Mr = 487.28,Dc = 1.663 g/cm3,F(000) = 502,μ = 0.749 mm-1,S = 1.060,the final R = 0.0377 and wR = 0.0893 for 3292 observed reflections with I 2σ(I).Complex 2 is isomorphous with 1,with a = 6.478(2),b = 19.052(7),c = 7.742(3) ,β = 92.690(4)o,V = 954.6(6) 3,Z = 2,Mr = 491.28,Dc = 1.709 g/cm3,F(000) = 506,μ = 0.971 mm-1,S = 1.035,the final R = 0.0425 and wR = 0.0809 for 3289 observed reflections with I 2σ(I).In the compounds,the mononuclear [M(L)2(H2O)4] units with trans-octahedral coordination geometry are linked into 3D architectures via hydrogen bonding(or second-sphere coordination) involving carboxylate groups and coordinated water molecules.The 3D networks illustrate a 3,8-connected net with Schlfli symbol(4·62)2(42·623·83). 展开更多
关键词 zwitterionic ligand manganese complex cobalt complex hydrogen bond topology
下载PDF
Synthesis, Crystal Structure, and Fluorescent and Thermal Stability Properties of Two New Cobalt(Ⅱ) Complexes with 2,2’-Bipy as Ligand 被引量:1
8
作者 LI Yu-Lin YANG Ying-Qun +1 位作者 MAO Fang-Fang CHEN Zhi-Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第5期769-776,670,共9页
Two new cobalt(Ⅱ)complexes[Co2(2,2?-bipy)2(dpa)2(H2O)5]·4H2O(1)and Co(2,2?-bipy)3(SO4)]·7.5H2O(2)have been synthesized with diaphonic acid(H2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.... Two new cobalt(Ⅱ)complexes[Co2(2,2?-bipy)2(dpa)2(H2O)5]·4H2O(1)and Co(2,2?-bipy)3(SO4)]·7.5H2O(2)have been synthesized with diaphonic acid(H2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.In 1,two neighboring cobalt(Ⅱ)ions are linked together by one bridging diaphonic acid group,forming an asymmetric dinuclear structure.1 crystallizes in triclinic,space group ■ with a=9.825(6),b=13.007(8),c=19.586(1)?,α=80.773(1)o,β=77.065(1)o,γ=85.902(1)o,Mr=431.4,V=2406.5(3)?3,Dc=1.48 g/cm3,Z=2,μ(MoKα)=0.767 mm-1,F(000)=1112,the final R=0.0379 and wR=0.0862.The central cobalt(Ⅱ)ions in 1 and 2 are coordinated with six atoms,forming distorted octahedral coordination geometry.The fluorescence and thermal stability properties of 1 and 2 are also reported. 展开更多
关键词 cobalt(Ⅱ) complex crystal structure fluorescence thermal stability
下载PDF
Studies on the Displacement Reaction of Trialkylaluminum with Ethylene Catalyzed by Nitrogen Chelate Cobalt Complexes
9
作者 Bin ZHOU Ren HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期135-137,共3页
The catalytic properties of a series of cobalt complexes containing bidenated nitrogen ligand for displacement reaction of trialkylaluminum with ethylene is reported. Effect of different reaction time, temperature an... The catalytic properties of a series of cobalt complexes containing bidenated nitrogen ligand for displacement reaction of trialkylaluminum with ethylene is reported. Effect of different reaction time, temperature and cobalt complexes containing different ligand on catalyst performance has been investigated. 展开更多
关键词 ETHYLENE displacement reaction trialkylaluminum cobalt complex.
下载PDF
Studies on Transition Metal Complexes of Schiff Base( Ⅰ )——Oxygen-carrying Properties of Cobalt( Ⅱ )Schiff Base Complexes
10
作者 LI Xiao-yan , SUN Hong-jian, CUI Xue-gui, LI Shu-Ian and LIU De-xin (Department of Applied Chemistry, Shandong University, Jinan, 250100) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第3期305-308,共4页
Introduction The compounds that can take up and release molecular oxygen reversibly is of significance because they can be used as model compounds for the study of the reversible oxygenation mechanisms involved in the... Introduction The compounds that can take up and release molecular oxygen reversibly is of significance because they can be used as model compounds for the study of the reversible oxygenation mechanisms involved in the very complex natural oxygen carriers, e.g., the hemoglobins and hemocyanins, and as the means of separating molecular oxygen from the air. The dioxygen carriers extensively studied are the Cobalt 展开更多
关键词 cobalt complex Schiff base THERMODYNAMICS Oxygen carrier
下载PDF
Catalytic Effect of Cobalt and Iron Complexes Incorporating Bis(2-aldiminoethyl)amine Ligands on Ethylene Oligomerization
11
作者 WANG Mei DAI Dong +2 位作者 ZHU Hong jun WANG Hui SUN Li cheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期231-234,共4页
Complexes [MCl 2{CH 3N(CH 2CH 2N[CDS1]CR 1R 2) 2}]((3, M=Co, R 1=H, R 2=Ph ; 4, M=Fe, R 1=H, \{R 2=Ph\}; 5, M=Co, R 1=R 2=Ph) were prepared and characterized by IR spectra and elemental analysis. The combination of ea... Complexes [MCl 2{CH 3N(CH 2CH 2N[CDS1]CR 1R 2) 2}]((3, M=Co, R 1=H, R 2=Ph ; 4, M=Fe, R 1=H, \{R 2=Ph\}; 5, M=Co, R 1=R 2=Ph) were prepared and characterized by IR spectra and elemental analysis. The combination of each of complexes 3-5 with ethylaluminoxane(EAO), respectively, was found to be moderately active for ethylene oligomerization to low carbon olefins. The activity of 113 kg oligomers·mol -1 Co·h -1 for complex 3(100 mol of EAO, 180 ℃ and 1 8 MPa ethylene) was observed with a selectivity of 93% to C 4-10 olefins, of which 96% were linear C4 10 olefins. The catalytic properties of complexes 3-5 were compared with those of analogous P,P coordinated complexes [MCl 2{CH 3N(CH 2CH 2PPh 2) 2}](1, M=Co; 2, \{M=\}Fe). 展开更多
关键词 cobalt and iron complexes Schiff base Bis(2-aldiminoethyl)amine Ethylene oligomerization Low carbon olefin
下载PDF
Synthesis and Crystal Structure of Cobalt(Ⅱ) and Copper(Ⅱ) Complexes Involving L-Aamino Alcohols
12
作者 罗梅 黄永华 +1 位作者 汪磊 尹浩 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第11期1655-1660,共6页
Two novel L-amino alcohol coordination cobalt and copper complexes I and Ⅱ were obtained separately from the direct reaction of L-plenylglycinol with Co(Ⅱ) acetate tetrahydrate in anhydrous ethanol and L-leucinol ... Two novel L-amino alcohol coordination cobalt and copper complexes I and Ⅱ were obtained separately from the direct reaction of L-plenylglycinol with Co(Ⅱ) acetate tetrahydrate in anhydrous ethanol and L-leucinol with Cu(Ⅱ) chloride dihydrate in anhydrous methanol. The structures of I and Ⅱ were determined by single-crystal X-ray diffraction and further characterized by elemental analysis and IR. For I: [Co3(C51H66N3O16)]2(OAc), monoclinic, space group P21, a = 15.022(3), b = 14.242(3), c = 28.922(6) A, β = 98.944(4)°, V = 6112(2) A3, Z = 4, Dc = 1.339 g/cm^3, the final R = 0.0860 for 21906 observed reflections with I 〉 2(I). For Ⅱ: Cu2[C24H58N4O7Cl]Cl, orthorhombic, space group P212121, a = 6.1861(13), b = 20.838(4), c = 28.274(6) , V = 3644.6(13) 3, Z = 4, Dc = 1.310 g/cm^3, the final R = 0.0642 for 11106 observed reflections with I 〉 2(I). The complexes were then used to catalyze the Henry reaction and catalytic activity determined by 1H NMR. 展开更多
关键词 novel cobalt and copper complexes L-plenylglycinol L-leucinol cobalt(Ⅱ) acetate tetrahydrate copper(Ⅱ) chloride dehydrate
下载PDF
Syntheses and Structures of Two New Cobalt Supramolecular Complexes, [Co(4,4'-bipy)_2(H_2O)_4]·[Co_2(4,4'-bipy)_3(H_2O)_8]·2TST·2(4,4'-bipy)·4H_2O and [Co(4,4'-bipy)_2(H_2O)_4]DSNT·4,4'-bipy
13
作者 余昀仿 韦永勤 吴克琛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第11期1519-1524,共6页
Two new cobalt(II) supramolecular complexes [Co(4,4'-bipy)2(H2O)4]·[Co2(4,4'-bipy)3(H2O)8]·2TST·2(4,4'-bipy)·4H2O 1 and [Co(4,4'-bipy)2(H2O)4]DSNT·4,4'-bipy 2 based upon t... Two new cobalt(II) supramolecular complexes [Co(4,4'-bipy)2(H2O)4]·[Co2(4,4'-bipy)3(H2O)8]·2TST·2(4,4'-bipy)·4H2O 1 and [Co(4,4'-bipy)2(H2O)4]DSNT·4,4'-bipy 2 based upon the assembly of Co(II), 4,4'-bipyridine (4,4'-bipy) and two new multifunctional organic ligands, 2,4,6-tris(4-sulfophenyl- amino)-1,3,5-triazine (H3TST) and 2,4-bis(p-sulfanilato)-6-diethylamino-1,3,5-triazine (H2DSNT), have been prepared by hydrothermal method and characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The crystal structure of 1 is of monoclinic, space group P21/n with a = 13.599(4), b = 18.988(6), c = 22.995(7) A, β = 90.273(6)°, V = 5938(3)A^3, Z = 4, C56H59Co1.5N13O17S3, Mr = 1370.74, Dc = 1.533 g/cm^3, μ = 0.613 mm^-1, F(000) = 2842, GOOF = 1.018, the final R = 0.0796 and wR = 0.1498 for 9019 observed reflections with I 〉 2σ(I). The crystal structure of 2 belongs to the monoclinic system, space group C2/c with a = 18.864(6), b = 14.283(5), c = 20.246(7)A, β = 107.799(6)°, V = 5194(3)A^3, Z = 4, C49H52CoN12O10S2, Mr = 1092.08, Dc = 1.397 g/cm^3, μ = 0.480 mm^-1, F(000) = 2276, GOOF = 1.059, the final R = 0.0665 and wR = 0.1900 for 4887 observed reflections with I 〉 2σ(I). The results of X-ray crystal structure analysis revealed that complexes 1 and 2 exhibit layered supramolecular frameworks stabilized by electrostatic interactions, π-π interactions and hydrogen bonds. 展开更多
关键词 supramolecular cobalt(Ⅱ) complex sulfonate ligand
下载PDF
Syntheses and Crystal Structures of Di-, Tri- and Tetra-nuclear Cobalt(II)-Lanthanide(III) Carboxylate Complexes
14
作者 崔勇 郑发鲲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第2期112-119,共8页
关键词 lanthanide complexes cobalt complexes carboxylate complexes SYNTHESES crystal structures
下载PDF
Syntheses and Crystal Structures of Cobalt(II) Chloride Complexes of 1,3-Bis(pyridyl-4-ylthio)propan-2-one
15
作者 WU Ben-Lai WU Ming-Yan GONG Ya-Qiong CHEN Bai-Quan HONG Mao-Chun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期511-516,共6页
Reactions of 1,3-bis(pyridyl-4-ylthio)propan-2-one L and COCl2·6H2O under different conditions gave two new cobalt(Ⅱ)-chloride-L complexes with distinct structures. Complex [Co(L)2Cl2]·0.5CH3OH}n 1 pr... Reactions of 1,3-bis(pyridyl-4-ylthio)propan-2-one L and COCl2·6H2O under different conditions gave two new cobalt(Ⅱ)-chloride-L complexes with distinct structures. Complex [Co(L)2Cl2]·0.5CH3OH}n 1 prepared by solvothermal treatment is a 3D network, whereas complex {[Co3(L)2Cl6(DMF)4]·2CH3OH·H2O} 2 obtained in DMF-diethyl ether system is a discrete acyclic trimer. Crystal data for 1: space group lbca, a = 15.993(4), b = 18.454(5), c = 21.506(6)A, V= 6347(3) ,A^3, Z = 8, Dc = 1.462 g/cm^3,μ = 1.005 mm^-1, F(000) = 2864, C26.5H26Cl2CoN4O2.5S4, Mr = 698.58, the final R = 0.0499 and wR = 0.1024. Crystal data for 2: space group P1^-, a = 9.9177(6), b = 11.0871 (4), c = 15.5490(12) ,A, α = 83.1834(14),β = 88.910(13), γ = 71.096( 11 )°, V = 1605.8(2) A^3, Z = 1, Dc = 1.362 g/cm^3,μ= 1.194 mm^-1, F(000) = 677, C40H62Cl6Co3N8O9S4, Mr = 1316.71, the final R = 0.0666 and wR =0.1575. 展开更多
关键词 cobalt chloride complex 1 3-bis(pyridyl-4-ylthio)propan-2-one crystal structure
下载PDF
Electrocatalytic hydrogen evolution from water at low overpotentials with cobalt complexes supported by redox-active bipyridyl-NHC donors
16
作者 Lizhu Chen Xiaojun Su Jonah W.Jurss 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第12期3187-3194,共8页
Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modific... Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modifications to the ligand framework is investigated across the catalyst series,which includes a non-macrocyclic derivative(1-Co)and 16-(2-Co)and 15-(3-Co)membered macrocycles.A structure-activity relationship is demonstrated,in which the macrocyclic complexes have greater activity compared to their non-macrocyclic counterpart with the most rigid catalyst,supported by the 15-membered macrocycle,performing best overall.Indeed,3-Co catalyzes H2 evolution from aqueous pH 4 acetate buffer with a Faradaic efficiency of 97%at a low overpotential of 330 mV.Mechanistic studies are consistent with formation of a cobalt-hydride species that is subsequently protonated to evolve H2 via a heterolytic pathway. 展开更多
关键词 Redox-active bipyridyl N-heterocyclic carbene donors cobalt complex ELECTROCATALYSIS Water splitting Hydrogen evolution
下载PDF
SYNTHETIC AND CATALYTIC PROPERTY STUDIES ON SILICA SUPPORTED BIS-(ACETYLACETONATO) COBALT(Ⅱ) COMPLEXES^(**)
17
作者 李小虎 陆云 林思聪 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第3期210-217,共8页
This paper reports mainly the preparation of silica supported acetylacetone ligands and their cobalt complexes, the characterization of their chemical structure, and the evaluation of their catalytic activity in the r... This paper reports mainly the preparation of silica supported acetylacetone ligands and their cobalt complexes, the characterization of their chemical structure, and the evaluation of their catalytic activity in the reaction for the preparation of ethers directly from alkanols and benzyl chloride. The results indicate that those silica supported β-diketone cobalt complexes (SACO) not only can simplify the reaction procedure of the ether preparation but also show a much higher catalytic activity in comparison with other homogeneous catalysts. In addition, SACO can be recovered and reused although their catalytic activity descend gradually as a result of the decrease in their cobalt content. 展开更多
关键词 SYNTHETIC AND CATALYTIC PROPERTY STUDIES ON SILICA SUPPORTED BIS cobalt complexes ACETYLACETONATO
下载PDF
Synthesis and Characterization of Dipeptide Schiff Base Complexes of Copper(Ⅱ), Zinc(Ⅱ), Nickel(Ⅱ) and Cobalt(Ⅱ)
18
作者 Guang Bin WANG Jin Ling WANG Fang Ming MIAO (Institute of Chemical Crystallography,Tianjin Normal University. Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期557-558,共2页
A new Schiff base (LK) obtained from 2, 4, -dihydroxybenzaldehyde and glycly-DL- phenylalanine reacted with Cu(II), Zn(II), Ni(II) and Co(II) to yield new complexes. The complexes were characterized by elemental an... A new Schiff base (LK) obtained from 2, 4, -dihydroxybenzaldehyde and glycly-DL- phenylalanine reacted with Cu(II), Zn(II), Ni(II) and Co(II) to yield new complexes. The complexes were characterized by elemental analyses, molar conductance, 1H NMR DTA, TG, IR and UV spectroscopy. In these complexes the ligand is coordinated to the metal through its phenolic oxygen, carboxyl oxygen, imino nitrogen and amide nitrogen. All complexes are non-electrolytes and four coordinated with 1:1(metal; ligand) stoichiometry. The probable structure of the complexes is suggested 展开更多
关键词 NICKEL Synthesis and Characterization of Dipeptide Schiff Base complexes of Copper ZINC and cobalt BASE
下载PDF
MM CALCULATIONS OF THE METAL-PROTEIN MODEL COMPLEXES Ⅰ.MOLECULAR FORCE FIELD FOR COBALT COMPEXES
19
作者 Wei Liang CAO Hong You GUO +2 位作者 Shi Lei XUE Xin Gang Ren Zuo Xing WangBeijing Institute of Chemical Technology,Beijing 100029 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第5期393-396,共4页
Cobalt-protein complexes play an important role in biochemical processes.The structure of the model molecule,Co(H_2O)_3SO_4(phen) has been studied by molecular mechanics.The molecular force field (MM2) parameters have... Cobalt-protein complexes play an important role in biochemical processes.The structure of the model molecule,Co(H_2O)_3SO_4(phen) has been studied by molecular mechanics.The molecular force field (MM2) parameters have been developed for the particular class of the complexes. 展开更多
关键词 CO MM CALCULATIONS OF THE METAL-PROTEIN MODEL complexes MOLECULAR FORCE FIELD FOR cobalt COMPEXES 耳卜
下载PDF
Cobalt-catalyzed photopromoted carbonylation of chloroalkanes in the presence of KI 被引量:1
20
作者 Ying Ping Jia Ying Na Cui +4 位作者 Jing Mei Yin Guang Yun Zhou Shen Min Li Da Bin Gao Xiang Sheng Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第9期1033-1036,共4页
The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co(OAc)2,CoCl2] in the presence of KI was carried out under ambient conditions.The results revealed that the cataly... The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co(OAc)2,CoCl2] in the presence of KI was carried out under ambient conditions.The results revealed that the catalytic activity of Co(OAc)2 was higher than that of CoCl2.A basic additive NaOAc was beneficial to the reaction.Interestingly,with NaOAc as an additive, Co(OAc)2 and CoCl2 exhibited similar catalytic activity.Preliminary work showed that the role of iodide ion was initially to form active iodoalkanes via substituting chloride ion in chloroalkanes in situ,and then,the carbonylation of iodoalkanes proceeded under irradiation. 展开更多
关键词 Photopromoted carbonylation CHLOROALKANES cobalt complexes: ki
下载PDF
上一页 1 2 41 下一页 到第
使用帮助 返回顶部