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
Two cobalt(Ⅱ) complexes of the Schiff base with morpholino or aza-crown ether pendants, CoL^1 and CoL^2, as mimic hydrolytic metalloenzyme, were used in catalytic hydrolysis of carboxylic ester (PNPP). The analys...Two cobalt(Ⅱ) complexes of the Schiff base with morpholino or aza-crown ether pendants, CoL^1 and CoL^2, as mimic hydrolytic metalloenzyme, were used in catalytic hydrolysis of carboxylic ester (PNPP). The analysis of specific absorption spectra of the hydrolytic reaction systems indicates that key intermediates, made up of PNPP and Co(Ⅱ) complexes, have been formed in reaction processes of the PNPP catalytic hydrolysis. The mechanism of PNPP catalytic hydrolysis has been proposed based on the analytic result of specific absorption spectrum. A kinetic mathematical model, applied to the calculation of the kinetic parameter of PNPP catalytic hydrolysis, has been established based on the mechanism proposed. The acid effect of buffer solution, structural effect of the complexes, and effect of temperature on the rate of PNPP hydrolysis catalyzed by the complexes have been also discussed.展开更多
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
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
A new metal-organic complex Co2(cbba)4(phen)2(μ2-OH2)(H2cbba=2-(4'-chlorine-benzoyl)benzoic acid,phen=1,10-phenanthroline) 1 has been hydrothermally synthesized and struc-turally characterized by single-cr...A new metal-organic complex Co2(cbba)4(phen)2(μ2-OH2)(H2cbba=2-(4'-chlorine-benzoyl)benzoic acid,phen=1,10-phenanthroline) 1 has been hydrothermally synthesized and struc-turally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectroscopy.The compound crystallizes in triclinic,space group P1 with a=10.7659(7),b=17.1856(11),c=19.2022(13),α=83.8120(10),β=84.9930(10),γ=87.2070(10)°,V=3515.8(4)3,C80H50Cl4Co2N4O13,Mr=1534.90,Dc=1.450 g/cm3,μ(MoKα)=0.693 mm-1,F(000)=1568,Z=2,the final R=0.0490 and wR=0.1092 for 8216 observed reflections(Ⅰ 〉2σ(Ⅰ)).In the crystal structure,the cobalt atom is six-coordinated with three carboxylate oxygen atoms from three different cbba ligands,one oxygen atom from coordinated water molecule and two nitrogen atoms from phen ligand,showing a distorted octahedral geometry.Furthermore,it exhibits a 3D supramolecular network through π-π and hydrogen bonding interactions.展开更多
A new metal-organic coordination polymer [Co(2-pya)2(4,4'-bipy)]2n-[(4,4'- bipy)0.5· H2O]2n (2-pya = 2-pyridinecarboxylic acid, 4,4'-bipy = 4,4'-bipyridine) 1 has been hydrothermally synthesized and s...A new metal-organic coordination polymer [Co(2-pya)2(4,4'-bipy)]2n-[(4,4'- bipy)0.5· H2O]2n (2-pya = 2-pyridinecarboxylic acid, 4,4'-bipy = 4,4'-bipyridine) 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 I41/a with a = b = 22.719(2), c = 10.710(2)/k, V = 5527.8(14) A3, C54H46N10Co2O10, Mr= 1112.87, Dc = 1.337 g/cm3,μ(MoKa) = 0.665 mm-1, F(000) = 2296, Z = 4, the final R = 0.0633 and wR = 0.1096 for 1261 observed reflections (I 〉 2σ(I)). It exhibits a one-dimensional chain-like structure constructed by mixed ligands of 2-pyridinedicarboxylic acid and 4,4'-bipyridine.展开更多
Three novel Schiff base cobalt(Ⅱ) complexes containing benzoaza-15-crown-5, CoL^1, CoL^2 and CoL^3 were synthesized and characterized, and these complexes were used in catalytic hydrolysis of carboxylic ester (PNP...Three novel Schiff base cobalt(Ⅱ) complexes containing benzoaza-15-crown-5, CoL^1, CoL^2 and CoL^3 were synthesized and characterized, and these complexes were used in catalytic hydrolysis of carboxylic ester (PNPP, p-nitrophenyl picolinate) as mimic hydrolytic metalloenzyme. The analysis of specific absorption spectra of the hydrolytic reaction systems indicated that the catalytic hydrolysis involved the key intermediates formed by PNPP with cobalt(Ⅱ) complexes. The CoL^3 bearing the electron withdrawing group shows better catalytic activity due to its stabilization effect on active species MLS^-. The catalytic mechanism of PNPP hydrolysis was also proposed. The kinetic parameter of PNPP catalytic hydrolysis has been calculated and the activation energy for the catalytic hydrolysis is 43.69, 39.76 and 35.44 kJ·mol^-1, respectively.展开更多
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
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...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 P1 with a=9.825(6),b=13.007(8),c=19.586(1)A,α=80.773(1)o,β=77.065(1)o,γ=85.902(1)o,Mr=431.4,V=2406.5(3)A^3,Dc=1.48 g/cm^3,Z=2,μ(Mo Kα)=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
The complete experimental IR spectra and vibrational analysis of the title complex Co(mnt)(dmbpy) were reported in this paper. The results show that the complex molecule has a planar geometry belonging to point group ...The complete experimental IR spectra and vibrational analysis of the title complex Co(mnt)(dmbpy) were reported in this paper. The results show that the complex molecule has a planar geometry belonging to point group C 2v and ground electronic state with spin quartet. A new method for analyzing vibrational spectra of complicated molecule is established. The essential of this method is to point out main fixed points and pivotal vibrational units in assignment for each fundamental band. Two new symbols η (heaving along the specified direction) and M (midpoint of a bond or unit) were defined for describing the vibrational modes accurately.展开更多
Cyclic voltammetry is used to study the electrochemical behavior of CoCl 2, Co(dppe) 2Cl 2 and Co(mbt S,N) 2(dppe) [Hmbt=2 mercaptobenzothiazole; dppe=1,2 (diphenylphosphino)] in DMF or MeCN solution with 0...Cyclic voltammetry is used to study the electrochemical behavior of CoCl 2, Co(dppe) 2Cl 2 and Co(mbt S,N) 2(dppe) [Hmbt=2 mercaptobenzothiazole; dppe=1,2 (diphenylphosphino)] in DMF or MeCN solution with 0.1 mol·L -1 Bu n 4NBF 4 as electrolyte on the Pt electrode. The results indicate that the reduction potential, transfer coefficient and diffusion coefficient of Co(Ⅱ), Co(dppe)(Ⅱ) and Co(mbt S,N) 2(dppe) in DMF and MeCN depend on the solvent coordinated species, the volume and structure of ion. This is the characterization of the synergistic coordination effect.展开更多
The crystal structure of [CoCl(C_7H_5N_2CH_2COPh)_4]Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl(C_7H_5N_2CH_2COPh)_4]+ cation and one Br- anion. In th...The crystal structure of [CoCl(C_7H_5N_2CH_2COPh)_4]Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl(C_7H_5N_2CH_2COPh)_4]+ cation and one Br- anion. In the [CoCl(C_7H_5N_2CH_2COPh)_4]+ cation, the coordination geometry of the central Co atom is square-pyramidal with four tertiary N atoms of benzimidazole from four α-(benzimidazol-1-yl)-hypnone ligands in the basal position and one chloride anion in the apical position. In the solid state, [CoCl(C_7H_5N_2CH_2COPh)_4]+ and Br- anion possess intermolecular and intramolecular interactions, which stabilize the crystal structure. The characterization of the title compound were also carried out by using elemeutal analysis, FTIR, UV spectrometries and TG-DSC.展开更多
The new compound 3-(2-pyridyl)-4-(p-methoxyphenyl)-5-(2-thienyl)-1,2,4-triazole L was synthesized and characterized by elemental analysis,IR,1H NMR,13C NMR,MS,UV and photoluminescent spectra.The complex CoL2(NC...The new compound 3-(2-pyridyl)-4-(p-methoxyphenyl)-5-(2-thienyl)-1,2,4-triazole L was synthesized and characterized by elemental analysis,IR,1H NMR,13C NMR,MS,UV and photoluminescent spectra.The complex CoL2(NCS)2 was prepared by the reaction of ligand L with Co(SCN)2,and its structure was characterized by single-crystal X-ray diffraction,IR,UV,elemental analysis and MS.The complex crystallizes in monoclinic,space group P21/n with a=13.7639(19),b=7.6641(11),c=18.409(3),β=101.549(3)o,V = 1902.6(5) 3,Z=2,C38H28CoN10O2S4,Mr=843.87,Dc=1.473 g/cm3,μ=0.720 mm-1,S=1.075,F(000)=866.0,the final R=0.0825 and wR=0.2149 for 2566 observed reflections(I2σ(I)).In the crystal structure,the cobalt atom adopts a distorted octahedral environment with two NCS-ions in the axial positions and two bidentate chelating L ligands in the equatorial plane.The extended 2D network of the complex is formed by intermolecular C–H…N hydrogen bonds together with π-π stacking interactions.展开更多
The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the ...The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the complex belongs to the triclinic system, space group P1, with a = 11.197(4), b = 13.309(5), c = 14.486(5) ]A, a = 78.827(13),β = 70.547(11), γ = 81.058(13)°, Mr = 996.77, S = 1.08, V= 1987.2(13) A3, Z = 2, Dc = 1.666 g/cm3, F(000) = 1032,μ = 1.131 mm^-1, R = 0.0633 and wR = 0.1293. According to the structural analysis, the Co( Ⅱ ) ion adopts a slightly distorted six-coordinated octahedral geometry. One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom. Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds, thus generating an infinite chain constructed by hydrogen bonds.展开更多
The oxygenation constants and thermodynamic parameter (△H°, △S°) of a series of novel Co (Ⅱ) complexes with phenol ether bridged dihydroxamic acids CoL^1-CoL^6 were measured, their catalytic performan...The oxygenation constants and thermodynamic parameter (△H°, △S°) of a series of novel Co (Ⅱ) complexes with phenol ether bridged dihydroxamic acids CoL^1-CoL^6 were measured, their catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The modulation of O2-binding capabilities and catalytic oxidation activities by X (X = Cl, OCH3) and Y (Y = H, CH3, Cl) groups bonded to the aromatic rings of the Co (Ⅱ) complexes were investigated.展开更多
The polymeric Co(Ⅱ) complex[Co(Hdhpc)(py)]n(1)(py = pyridine,H3dhpc =2,6-dihydroxypyridine-4-carboxyl acid) was prepared and characterized.X-ray diffraction data revealed that the compound crystallizes in d...The polymeric Co(Ⅱ) complex[Co(Hdhpc)(py)]n(1)(py = pyridine,H3dhpc =2,6-dihydroxypyridine-4-carboxyl acid) was prepared and characterized.X-ray diffraction data revealed that the compound crystallizes in dimorphic 1α and 1β forms at room and low temperature,respectively.The former crystallizes in the orthorhombic crystal system,space group Pbcm with a =7.209(1),b = 14.834(3),c = 15.376(3) A°,V= 1644.3(5)A°3,Z = 4,C(16)H(13)CoN3O4,Mr = 370.22,Dc= 1.496 g/cm^3,F(000) = 756,μ = 1.068 mm^-1,R = 0.0633 and wR = 0.1192.While 1β is attributed to the monoclinic space group C2/c with a = 32.102(4),b = 7.022,c = 14.945(2)A°,β = 109.052(5)°,V= 3184.4(6) A°3,Z= 8,Dc= 1.544 g/cm^3,F(000) = 1512,μ = 1.103 mm^-1,R = 0.0428 and wR =0.0797.The conformation changes of pyridines between Co-citrazinate planes leading to a reversible single-crystal to single-crystal transformation.The variable temperature magnetic data indicate a weak ferrimagnetism.展开更多
Two cobalt(Ⅱ) compounds,Co(2,2-bpy) 2 Br 2 (1,2,2-bpy=2,2-bipyridyl) and Co(1,10-phen) 2 Br 2 (2,1,10-phen=1,10-phenanthroline),have been prepared under ionothermal reactions using the 1-propyl-3-methylimid...Two cobalt(Ⅱ) compounds,Co(2,2-bpy) 2 Br 2 (1,2,2-bpy=2,2-bipyridyl) and Co(1,10-phen) 2 Br 2 (2,1,10-phen=1,10-phenanthroline),have been prepared under ionothermal reactions using the 1-propyl-3-methylimidazolium bromide ionic liquid solvent.Single-crystal X-ray analyses reveal that 1 crystallizes in a monoclinic space group P2 1 /c,with a=8.5509(13),b=14.804(2),c=15.650(2),β=97.119(2) o,V=1965.8(5) 3,Z=4,C 20 H 16 Br 2 N 4 Co,M r=531.12,D c=1.795 g/cm 3,μ=4.950 mm-1,F(000)=1044,the final R=0.0467 and wR=0.0736 for 2291 observed reflections with I 2σ(Ⅰ).Complex 2 crystallizes in a monoclinic space group P2 1 /n,with a=10.4237(8),b=16.8657(12),c=12.4945(9)b,β=102.110(1) o,V=2147.7(3) 3,Z=4,C 24 H 16 Br 2 N 4 Co,M r=579.16,D c=1.791 g/cm 3,μ=4.540 mm-1,F(000)=1140,the final R=0.0431 and wR=0.1042 for 3470 observed reflections with I 2σ(Ⅰ).The mononuclear molecules of 1 are linked by the C-H···Br hydrogen bonds and π-π interactions to form a three-dimensional supramolecular framework structure.The C-H···Br hydrogen bonds and π-π interactions link the mononuclear molecules of 2 to give a two-dimensional layer structure.展开更多
Reactions of pyridine-2,6-dicarboxylic acid(H2PDA) with cobalt(Ⅱ) acetate resul-ted in two cobalt(Ⅱ) complexes,[Co(HPDA)2].2H2O.0.5CH3OH(1) and [Co2(PDA)2(H2O)5].2H2O(2),which were characterized by s...Reactions of pyridine-2,6-dicarboxylic acid(H2PDA) with cobalt(Ⅱ) acetate resul-ted in two cobalt(Ⅱ) complexes,[Co(HPDA)2].2H2O.0.5CH3OH(1) and [Co2(PDA)2(H2O)5].2H2O(2),which were characterized by single-crystal X-ray diffraction,IR and electronic absorption spectra.For both complexes,every cobalt atom lies in peudo-octahedral coordination geometry,and the whole structures present 3D frameworks linked by π-π stacking interactions and extensive hydrogen bonds.Magnetic studies showed λ =-83.38 cm-1 for(1) and g = 2.50 and J =-1.38 cm-1 for(2).展开更多
Four new heterotrinuclear complexes have been synthesized and characterized, namely [(CoL 2) 2Cu(pbaOH)](ClO 4) 2, where pbaOH denotes 2 hydroxy 1,3 propylenebis(oxamato) and L stands for 1,10 phenanthroline(p...Four new heterotrinuclear complexes have been synthesized and characterized, namely [(CoL 2) 2Cu(pbaOH)](ClO 4) 2, where pbaOH denotes 2 hydroxy 1,3 propylenebis(oxamato) and L stands for 1,10 phenanthroline(phen), 5 nitro 1,10 phenanthroline(NO 2 phen), 2,2 bipyridyl(bpy) and 4,4 dimethyl 2,2 bipyridyl(Me 2bpy). The temperature dependence of the magnetic susceptibility of [(Cophen 2) 2Cu(pbaOH)](ClO 4) 2·H 2O has been studied in the range of 4—300 K, the plot of χ M T vs. T exhibits a minimum at about 120 K, but abnormal magnetic behavior below 78 K.展开更多
文摘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.
基金Project supported by the Educational Department of Sichuan Government (No.2005D007) and the National Natural Science Foundation of China (Nos.20173038, 20107004).
文摘Two cobalt(Ⅱ) complexes of the Schiff base with morpholino or aza-crown ether pendants, CoL^1 and CoL^2, as mimic hydrolytic metalloenzyme, were used in catalytic hydrolysis of carboxylic ester (PNPP). The analysis of specific absorption spectra of the hydrolytic reaction systems indicates that key intermediates, made up of PNPP and Co(Ⅱ) complexes, have been formed in reaction processes of the PNPP catalytic hydrolysis. The mechanism of PNPP catalytic hydrolysis has been proposed based on the analytic result of specific absorption spectrum. A kinetic mathematical model, applied to the calculation of the kinetic parameter of PNPP catalytic hydrolysis, has been established based on the mechanism proposed. The acid effect of buffer solution, structural effect of the complexes, and effect of temperature on the rate of PNPP hydrolysis catalyzed by the complexes have been also discussed.
基金Supported by the National Natural Science Foundation of China (No. 60978059)Program for New Century Excellent Talents in University (NCET-10-0176)the Natural Science Foundation of Jilin Province (No. 20090527)
文摘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.
基金supported by the National Natural Science Foundation of China(No.21571093)the Program for Science&Technology Innovation Talents in Universities of Henan Province(No.14HASTIT017)+1 种基金the Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.14IRTSTHN008)the Foundation of Education Committee of Henan Province(No.142300410301)
文摘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.
基金supported by the Science and Technology Research Projects of the Education Department of Jilin Province (No. 2009. 272)
文摘A new metal-organic complex Co2(cbba)4(phen)2(μ2-OH2)(H2cbba=2-(4'-chlorine-benzoyl)benzoic acid,phen=1,10-phenanthroline) 1 has been hydrothermally synthesized and struc-turally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectroscopy.The compound crystallizes in triclinic,space group P1 with a=10.7659(7),b=17.1856(11),c=19.2022(13),α=83.8120(10),β=84.9930(10),γ=87.2070(10)°,V=3515.8(4)3,C80H50Cl4Co2N4O13,Mr=1534.90,Dc=1.450 g/cm3,μ(MoKα)=0.693 mm-1,F(000)=1568,Z=2,the final R=0.0490 and wR=0.1092 for 8216 observed reflections(Ⅰ 〉2σ(Ⅰ)).In the crystal structure,the cobalt atom is six-coordinated with three carboxylate oxygen atoms from three different cbba ligands,one oxygen atom from coordinated water molecule and two nitrogen atoms from phen ligand,showing a distorted octahedral geometry.Furthermore,it exhibits a 3D supramolecular network through π-π and hydrogen bonding interactions.
基金supported by Science and Technology Research Projects of the Education Office of Jilin Province (No. 2007. 213)
文摘A new metal-organic coordination polymer [Co(2-pya)2(4,4'-bipy)]2n-[(4,4'- bipy)0.5· H2O]2n (2-pya = 2-pyridinecarboxylic acid, 4,4'-bipy = 4,4'-bipyridine) 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 I41/a with a = b = 22.719(2), c = 10.710(2)/k, V = 5527.8(14) A3, C54H46N10Co2O10, Mr= 1112.87, Dc = 1.337 g/cm3,μ(MoKa) = 0.665 mm-1, F(000) = 2296, Z = 4, the final R = 0.0633 and wR = 0.1096 for 1261 observed reflections (I 〉 2σ(I)). It exhibits a one-dimensional chain-like structure constructed by mixed ligands of 2-pyridinedicarboxylic acid and 4,4'-bipyridine.
基金Project supported by the Educational Department of Sichuan Government (No. 2005D007) and the National Natural Science Foundation of China (Nos. 20173038, 20107004).
文摘Three novel Schiff base cobalt(Ⅱ) complexes containing benzoaza-15-crown-5, CoL^1, CoL^2 and CoL^3 were synthesized and characterized, and these complexes were used in catalytic hydrolysis of carboxylic ester (PNPP, p-nitrophenyl picolinate) as mimic hydrolytic metalloenzyme. The analysis of specific absorption spectra of the hydrolytic reaction systems indicated that the catalytic hydrolysis involved the key intermediates formed by PNPP with cobalt(Ⅱ) complexes. The CoL^3 bearing the electron withdrawing group shows better catalytic activity due to its stabilization effect on active species MLS^-. The catalytic mechanism of PNPP hydrolysis was also proposed. The kinetic parameter of PNPP catalytic hydrolysis has been calculated and the activation energy for the catalytic hydrolysis is 43.69, 39.76 and 35.44 kJ·mol^-1, respectively.
文摘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.
基金Supported by Hunan Provincial Natural Science Foundation of China(2019JJ60021)the Scientific Research Found of Hunan Provincial Education Department of China(17A049,17C0226)Industry and Research Key Project of Hengyang City(2018KJ016)
文摘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 P1 with a=9.825(6),b=13.007(8),c=19.586(1)A,α=80.773(1)o,β=77.065(1)o,γ=85.902(1)o,Mr=431.4,V=2406.5(3)A^3,Dc=1.48 g/cm^3,Z=2,μ(Mo Kα)=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.
基金Supported by the National Natural Science F oundation of China( No. 2 97710 2 5 )
文摘The complete experimental IR spectra and vibrational analysis of the title complex Co(mnt)(dmbpy) were reported in this paper. The results show that the complex molecule has a planar geometry belonging to point group C 2v and ground electronic state with spin quartet. A new method for analyzing vibrational spectra of complicated molecule is established. The essential of this method is to point out main fixed points and pivotal vibrational units in assignment for each fundamental band. Two new symbols η (heaving along the specified direction) and M (midpoint of a bond or unit) were defined for describing the vibrational modes accurately.
文摘Cyclic voltammetry is used to study the electrochemical behavior of CoCl 2, Co(dppe) 2Cl 2 and Co(mbt S,N) 2(dppe) [Hmbt=2 mercaptobenzothiazole; dppe=1,2 (diphenylphosphino)] in DMF or MeCN solution with 0.1 mol·L -1 Bu n 4NBF 4 as electrolyte on the Pt electrode. The results indicate that the reduction potential, transfer coefficient and diffusion coefficient of Co(Ⅱ), Co(dppe)(Ⅱ) and Co(mbt S,N) 2(dppe) in DMF and MeCN depend on the solvent coordinated species, the volume and structure of ion. This is the characterization of the synergistic coordination effect.
文摘The crystal structure of [CoCl(C_7H_5N_2CH_2COPh)_4]Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl(C_7H_5N_2CH_2COPh)_4]+ cation and one Br- anion. In the [CoCl(C_7H_5N_2CH_2COPh)_4]+ cation, the coordination geometry of the central Co atom is square-pyramidal with four tertiary N atoms of benzimidazole from four α-(benzimidazol-1-yl)-hypnone ligands in the basal position and one chloride anion in the apical position. In the solid state, [CoCl(C_7H_5N_2CH_2COPh)_4]+ and Br- anion possess intermolecular and intramolecular interactions, which stabilize the crystal structure. The characterization of the title compound were also carried out by using elemeutal analysis, FTIR, UV spectrometries and TG-DSC.
基金supported by the Natural Science Foundation of Anhui Provincial Education Commission (Nos KJ2007B231 and 2006jql224)
文摘The new compound 3-(2-pyridyl)-4-(p-methoxyphenyl)-5-(2-thienyl)-1,2,4-triazole L was synthesized and characterized by elemental analysis,IR,1H NMR,13C NMR,MS,UV and photoluminescent spectra.The complex CoL2(NCS)2 was prepared by the reaction of ligand L with Co(SCN)2,and its structure was characterized by single-crystal X-ray diffraction,IR,UV,elemental analysis and MS.The complex crystallizes in monoclinic,space group P21/n with a=13.7639(19),b=7.6641(11),c=18.409(3),β=101.549(3)o,V = 1902.6(5) 3,Z=2,C38H28CoN10O2S4,Mr=843.87,Dc=1.473 g/cm3,μ=0.720 mm-1,S=1.075,F(000)=866.0,the final R=0.0825 and wR=0.2149 for 2566 observed reflections(I2σ(I)).In the crystal structure,the cobalt atom adopts a distorted octahedral environment with two NCS-ions in the axial positions and two bidentate chelating L ligands in the equatorial plane.The extended 2D network of the complex is formed by intermolecular C–H…N hydrogen bonds together with π-π stacking interactions.
基金Supported by the Natural Science Foundation of Guangxi Province (No. 0339034)the Science Research Foundation of Guangxi Normal University
文摘The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the complex belongs to the triclinic system, space group P1, with a = 11.197(4), b = 13.309(5), c = 14.486(5) ]A, a = 78.827(13),β = 70.547(11), γ = 81.058(13)°, Mr = 996.77, S = 1.08, V= 1987.2(13) A3, Z = 2, Dc = 1.666 g/cm3, F(000) = 1032,μ = 1.131 mm^-1, R = 0.0633 and wR = 0.1293. According to the structural analysis, the Co( Ⅱ ) ion adopts a slightly distorted six-coordinated octahedral geometry. One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom. Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds, thus generating an infinite chain constructed by hydrogen bonds.
基金supported by the National Natural Science Foundation of China(No.2007205).
文摘The oxygenation constants and thermodynamic parameter (△H°, △S°) of a series of novel Co (Ⅱ) complexes with phenol ether bridged dihydroxamic acids CoL^1-CoL^6 were measured, their catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The modulation of O2-binding capabilities and catalytic oxidation activities by X (X = Cl, OCH3) and Y (Y = H, CH3, Cl) groups bonded to the aromatic rings of the Co (Ⅱ) complexes were investigated.
基金supported by the National Natural Science Foundation of China(No.21173074,J1210040 and J1103312)
文摘The polymeric Co(Ⅱ) complex[Co(Hdhpc)(py)]n(1)(py = pyridine,H3dhpc =2,6-dihydroxypyridine-4-carboxyl acid) was prepared and characterized.X-ray diffraction data revealed that the compound crystallizes in dimorphic 1α and 1β forms at room and low temperature,respectively.The former crystallizes in the orthorhombic crystal system,space group Pbcm with a =7.209(1),b = 14.834(3),c = 15.376(3) A°,V= 1644.3(5)A°3,Z = 4,C(16)H(13)CoN3O4,Mr = 370.22,Dc= 1.496 g/cm^3,F(000) = 756,μ = 1.068 mm^-1,R = 0.0633 and wR = 0.1192.While 1β is attributed to the monoclinic space group C2/c with a = 32.102(4),b = 7.022,c = 14.945(2)A°,β = 109.052(5)°,V= 3184.4(6) A°3,Z= 8,Dc= 1.544 g/cm^3,F(000) = 1512,μ = 1.103 mm^-1,R = 0.0428 and wR =0.0797.The conformation changes of pyridines between Co-citrazinate planes leading to a reversible single-crystal to single-crystal transformation.The variable temperature magnetic data indicate a weak ferrimagnetism.
基金supported by the NNSFC (20901033)NSF of Jiangxi Province(2009GZH0056)the Key Project of Education Department of Jiangxi Province (GJJ10016)
文摘Two cobalt(Ⅱ) compounds,Co(2,2-bpy) 2 Br 2 (1,2,2-bpy=2,2-bipyridyl) and Co(1,10-phen) 2 Br 2 (2,1,10-phen=1,10-phenanthroline),have been prepared under ionothermal reactions using the 1-propyl-3-methylimidazolium bromide ionic liquid solvent.Single-crystal X-ray analyses reveal that 1 crystallizes in a monoclinic space group P2 1 /c,with a=8.5509(13),b=14.804(2),c=15.650(2),β=97.119(2) o,V=1965.8(5) 3,Z=4,C 20 H 16 Br 2 N 4 Co,M r=531.12,D c=1.795 g/cm 3,μ=4.950 mm-1,F(000)=1044,the final R=0.0467 and wR=0.0736 for 2291 observed reflections with I 2σ(Ⅰ).Complex 2 crystallizes in a monoclinic space group P2 1 /n,with a=10.4237(8),b=16.8657(12),c=12.4945(9)b,β=102.110(1) o,V=2147.7(3) 3,Z=4,C 24 H 16 Br 2 N 4 Co,M r=579.16,D c=1.791 g/cm 3,μ=4.540 mm-1,F(000)=1140,the final R=0.0431 and wR=0.1042 for 3470 observed reflections with I 2σ(Ⅰ).The mononuclear molecules of 1 are linked by the C-H···Br hydrogen bonds and π-π interactions to form a three-dimensional supramolecular framework structure.The C-H···Br hydrogen bonds and π-π interactions link the mononuclear molecules of 2 to give a two-dimensional layer structure.
基金Supported by the Doctoral Laboratory of Xi’an Shiyou University
文摘Reactions of pyridine-2,6-dicarboxylic acid(H2PDA) with cobalt(Ⅱ) acetate resul-ted in two cobalt(Ⅱ) complexes,[Co(HPDA)2].2H2O.0.5CH3OH(1) and [Co2(PDA)2(H2O)5].2H2O(2),which were characterized by single-crystal X-ray diffraction,IR and electronic absorption spectra.For both complexes,every cobalt atom lies in peudo-octahedral coordination geometry,and the whole structures present 3D frameworks linked by π-π stacking interactions and extensive hydrogen bonds.Magnetic studies showed λ =-83.38 cm-1 for(1) and g = 2.50 and J =-1.38 cm-1 for(2).
文摘Four new heterotrinuclear complexes have been synthesized and characterized, namely [(CoL 2) 2Cu(pbaOH)](ClO 4) 2, where pbaOH denotes 2 hydroxy 1,3 propylenebis(oxamato) and L stands for 1,10 phenanthroline(phen), 5 nitro 1,10 phenanthroline(NO 2 phen), 2,2 bipyridyl(bpy) and 4,4 dimethyl 2,2 bipyridyl(Me 2bpy). The temperature dependence of the magnetic susceptibility of [(Cophen 2) 2Cu(pbaOH)](ClO 4) 2·H 2O has been studied in the range of 4—300 K, the plot of χ M T vs. T exhibits a minimum at about 120 K, but abnormal magnetic behavior below 78 K.