A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py...A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713.展开更多
Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal s...Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal sources and N,N-dimethylformamide was employed as a solvent as well as a reductant to produce Cu(Ⅰ) complexes.(ⅱ) An iodide-containing compound was utilized as a ligand and iodide source to prepare complexes.An in situ metalligand reaction occurred and an iodide-bridged copper complex was generated.(ⅲ) A series of aldehydes were added to the reaction systems to induce in situ metal-ligand reactions between the aldehydes and the imidazo[1,5-a]pyridine derivatives,producing polydentate ligand scaffolds.Eight complexes were prepared and characterized.The catalytic activities of these complexes toward the ketalization of ketones by ethylene glycol were investigated.With the exception of complex4,the remaining seven complexes all showed high catalytic activity.The lower activity of 4 may be due to the larger radius of bridging iodide ions and the shorter Cu(Ⅰ)…Cu(Ⅰ) distance.CCDC:2357696,1·2CH_(2)Cl_(2);2357697,2;2018292,3;2092192,4;2092190,5;2155557,6;2406155,7;2406156,8·EtOH.展开更多
The kinetic behavior of leaching copper from low grade copper oxide ore was investigated. The effects of leaching temperature, H2SO4 concentration, particle size of crude ore and agitation rate on the leaching efficie...The kinetic behavior of leaching copper from low grade copper oxide ore was investigated. The effects of leaching temperature, H2SO4 concentration, particle size of crude ore and agitation rate on the leaching efficiency of copper were also evaluated. And the kinetic equations of the leaching process were obtained. The results show that the leaching process can be described with a reaction model of shrinking core. The reaction can be divided into three stages. The first stage is the dissolution of free copper oxide and copper oxide wrapped by hematite-limonite ore. At this stage, the leaching efficiency is very fast （leaching efficiency is larger than 60%）. The second stage is the leaching of diffiuent copper oxides, whose apparent activation energy is 43.26 kJ/mol. During this process, the chemical reaction is the control step, and the reaction order of H2SO4 is 0.433 84. The third stage is the leaching of copper oxide wrapped by hematite-limonite and silicate ore with apparent activation energy of 16.08 kJ/mol, which belongs to the mixed control.展开更多
A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b =...A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.展开更多
The complex [Cu(m-NBA)(2,2'-bipy)(H2O)2]·m-NBA·H2O was obtained by self-assembly of m-nitroben-zoic acid,2,2'-bipyridine and copper(Ⅱ).The crystal structure of the complex has been determined by X-r...The complex [Cu(m-NBA)(2,2'-bipy)(H2O)2]·m-NBA·H2O was obtained by self-assembly of m-nitroben-zoic acid,2,2'-bipyridine and copper(Ⅱ).The crystal structure of the complex has been determined by X-ray diffraction single crystal structure analysis.The crystal belongs to monoclinic system,space group P21/n.The cell parameters are:a=0.705 65(9) nm,b=2.901 2(4) nm,c=1.271 52(2) nm;β=92.895(2)°,and V=2.599 8(6) nm3,Dc= 1.551 g·cm-3,Z=4,μ(Mo Kα)=9.09 cm-1,F(000)=1 244,R1=0.040 7,wR2=0.085 5[I>2σ(I)].The crystal structure shows that the copper(Ⅱ) ion is coordinated with two nitrogen atoms from one 2,2'-bipyridine molecule,one oxygen atom from one m-nitrobenzoic acid molecule and and two oxygen atoms from two water molecules,forming a distorted coordination square-pyramid.The cyclic voltametric behavior of the complex was also studied.展开更多
A new copper! coordination polymer, Cu(p-BDOA)(2,2′-bipy)·H2On (p-BDOA2-=benzene-1,4-dioxy- acetate dianion; 2,2′-bipy=2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR, TG and ...A new copper! coordination polymer, Cu(p-BDOA)(2,2′-bipy)·H2On (p-BDOA2-=benzene-1,4-dioxy- acetate dianion; 2,2′-bipy=2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The Crystal crystallizes in orthorhombic system, the space group is P212121, with the unit cell parameters a=0.698 4(1) nm, b=1.559 7(3) nm, c=1.750 6(4) nm and V=1.906 8(7) nm3, Mr= 461.91, Z=4, R=0.0575, wR=0.0783. Each copper! atom is six-coordinated and displays a distorted square pyramidal geometry with a one-capped base by one very long semicoordinate Cu-O(carboxylate) bond. Adjacent Cu! ions are bridged by carboxylate groups, resulting in a one-dimensional helical chain. The adjacent Cu…Cu distance within the polymeric chain is 1.3484 nm. Furthermore, such chains are linked through hydrogen bonds and π-πstacking interactions to form supramolecular network. CCDC: 219234.展开更多
The title complex has been synthesized by using terephthalic acid (PTA), 1,10-phenanthroline (phen) and copper monohydrate. It crystallizes in monoclinic space group C2/c with a=2.9590(2) nm, b=1.4664(10) nm, c=1.764 ...The title complex has been synthesized by using terephthalic acid (PTA), 1,10-phenanthroline (phen) and copper monohydrate. It crystallizes in monoclinic space group C2/c with a=2.9590(2) nm, b=1.4664(10) nm, c=1.764 3(12) nm, β=105.593(11)°, V=7.372(9) nm3, Dc=1.489 g·cm-3, Z=8, F(000)=3 416, R1=0.043 6, wR2= 0.1519. The crystal structure shows that the copper atom is coordinated with four nitrogen atoms from two phens and one oxygen atom from one terephthalic acid, forming a distorted square-pyramid coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 277047.展开更多
文摘A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713.
文摘Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal sources and N,N-dimethylformamide was employed as a solvent as well as a reductant to produce Cu(Ⅰ) complexes.(ⅱ) An iodide-containing compound was utilized as a ligand and iodide source to prepare complexes.An in situ metalligand reaction occurred and an iodide-bridged copper complex was generated.(ⅲ) A series of aldehydes were added to the reaction systems to induce in situ metal-ligand reactions between the aldehydes and the imidazo[1,5-a]pyridine derivatives,producing polydentate ligand scaffolds.Eight complexes were prepared and characterized.The catalytic activities of these complexes toward the ketalization of ketones by ethylene glycol were investigated.With the exception of complex4,the remaining seven complexes all showed high catalytic activity.The lower activity of 4 may be due to the larger radius of bridging iodide ions and the shorter Cu(Ⅰ)…Cu(Ⅰ) distance.CCDC:2357696,1·2CH_(2)Cl_(2);2357697,2;2018292,3;2092192,4;2092190,5;2155557,6;2406155,7;2406156,8·EtOH.
基金Project(2005BA639C) supported by the National Science and Technology Development of China
文摘The kinetic behavior of leaching copper from low grade copper oxide ore was investigated. The effects of leaching temperature, H2SO4 concentration, particle size of crude ore and agitation rate on the leaching efficiency of copper were also evaluated. And the kinetic equations of the leaching process were obtained. The results show that the leaching process can be described with a reaction model of shrinking core. The reaction can be divided into three stages. The first stage is the dissolution of free copper oxide and copper oxide wrapped by hematite-limonite ore. At this stage, the leaching efficiency is very fast （leaching efficiency is larger than 60%）. The second stage is the leaching of diffiuent copper oxides, whose apparent activation energy is 43.26 kJ/mol. During this process, the chemical reaction is the control step, and the reaction order of H2SO4 is 0.433 84. The third stage is the leaching of copper oxide wrapped by hematite-limonite and silicate ore with apparent activation energy of 16.08 kJ/mol, which belongs to the mixed control.
基金Project(21001118)supported by National Natural Science Foundation of ChinaProject(12JJ3016)supported by Natural Science Foundation of Hunan Province,China
文摘A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.
文摘The complex [Cu(m-NBA)(2,2'-bipy)(H2O)2]·m-NBA·H2O was obtained by self-assembly of m-nitroben-zoic acid,2,2'-bipyridine and copper(Ⅱ).The crystal structure of the complex has been determined by X-ray diffraction single crystal structure analysis.The crystal belongs to monoclinic system,space group P21/n.The cell parameters are:a=0.705 65(9) nm,b=2.901 2(4) nm,c=1.271 52(2) nm;β=92.895(2)°,and V=2.599 8(6) nm3,Dc= 1.551 g·cm-3,Z=4,μ(Mo Kα)=9.09 cm-1,F(000)=1 244,R1=0.040 7,wR2=0.085 5[I>2σ(I)].The crystal structure shows that the copper(Ⅱ) ion is coordinated with two nitrogen atoms from one 2,2'-bipyridine molecule,one oxygen atom from one m-nitrobenzoic acid molecule and and two oxygen atoms from two water molecules,forming a distorted coordination square-pyramid.The cyclic voltametric behavior of the complex was also studied.
文摘A new copper! coordination polymer, Cu(p-BDOA)(2,2′-bipy)·H2On (p-BDOA2-=benzene-1,4-dioxy- acetate dianion; 2,2′-bipy=2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The Crystal crystallizes in orthorhombic system, the space group is P212121, with the unit cell parameters a=0.698 4(1) nm, b=1.559 7(3) nm, c=1.750 6(4) nm and V=1.906 8(7) nm3, Mr= 461.91, Z=4, R=0.0575, wR=0.0783. Each copper! atom is six-coordinated and displays a distorted square pyramidal geometry with a one-capped base by one very long semicoordinate Cu-O(carboxylate) bond. Adjacent Cu! ions are bridged by carboxylate groups, resulting in a one-dimensional helical chain. The adjacent Cu…Cu distance within the polymeric chain is 1.3484 nm. Furthermore, such chains are linked through hydrogen bonds and π-πstacking interactions to form supramolecular network. CCDC: 219234.
文摘The title complex has been synthesized by using terephthalic acid (PTA), 1,10-phenanthroline (phen) and copper monohydrate. It crystallizes in monoclinic space group C2/c with a=2.9590(2) nm, b=1.4664(10) nm, c=1.764 3(12) nm, β=105.593(11)°, V=7.372(9) nm3, Dc=1.489 g·cm-3, Z=8, F(000)=3 416, R1=0.043 6, wR2= 0.1519. The crystal structure shows that the copper atom is coordinated with four nitrogen atoms from two phens and one oxygen atom from one terephthalic acid, forming a distorted square-pyramid coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 277047.
