Two new Zn(Ⅱ)-MOFs were synthesized based on an asymmetric Schiff-base ligand LH, which is obtained by the condensation of 5-formyl-8-hydroxyquinoline and 3-pyridinecar- boxylic acid hydrazide. In different mixed s...Two new Zn(Ⅱ)-MOFs were synthesized based on an asymmetric Schiff-base ligand LH, which is obtained by the condensation of 5-formyl-8-hydroxyquinoline and 3-pyridinecar- boxylic acid hydrazide. In different mixed solvents, we get two new isomorphism compounds, [Zn(L)2]'CaHsO2-2MeOH (1) and [Zn(L)2]'CH2CIz'2MeOH (2). Compounds 1 and 2 have been characterized by single-crystal X-ray diffraction, elemental analysis and IR. Compound 1 crystallizes in monoclinic, space group P2/c, with a - 13.856(4), b = 14.156(4), c = 9.620(3)А, β = 110.167(5)°, V = 1771.3(9) /k3, Dc = 1.500 g/cm3, C3sH3sNsOsZn, Mr = 800.13, F(000) = 832, p(MoKa) = 0.761 mm-1, Z = 2, the final R = 0.0596 and wR = 0.1221 for 2112 observed reflections (I 〉 2σ(0). Compound 2 belongs to monoclinic, space group P21/c, with a = 13.575(3), b = 14.130(3), c = 9.485(2) A, β = 107.908(3)°, V= 1731.2(6) A3, Dc = 1.529 g/cm3, CasH32C12NsO6Zn, Mr = 796.96, F(000) = 820, g(MoKa) = 0.926 mm-1, Z = 2, the final R -- 0.0527 and wR = 0.1395 for 2501 observed reflections (I 〉 2σ-(/)). The Zn(II) centers in both 1 and 2 display a distorted octahedral coordination geometry. The octahedral Zn(lI) nodes and L linkages build up 2-D nets consisting of parallelogram-like grids in the ab plane. The neighboring nets stack through hydrogen bonds to generate 3-D rhombic channels. In 1, the 1,4-dioxane and MeOH guests alternatively arrange in the channels and effectively take up the free space; while in 2, the CH2CI/guests are arranged in the channels. In addition, the encapsulated MeOH molecules are bonded to the framework by hydrogen bonds.展开更多
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
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
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
One novel discrete coordination molecule with Ag^(I) centers,namely[Ag_(3)(L)_(3)(ClO_(4))_(3)]·3CH_(2)Cl_(2)·6CH_(3)OH·1.5H_(2)O (1),has been synthesized based on the double Schiff-base ligand,3,6-bis[...One novel discrete coordination molecule with Ag^(I) centers,namely[Ag_(3)(L)_(3)(ClO_(4))_(3)]·3CH_(2)Cl_(2)·6CH_(3)OH·1.5H_(2)O (1),has been synthesized based on the double Schiff-base ligand,3,6-bis[2-(4-oxidequinoxaline)-yl]-4,5-diaza-3,5-octadiene (L) and AgClO_4.The obtained Ag(I) compound was fully characterized by infrared spectroscopy,elemental analysis,and single-crystal X-ray diffraction.1 is of trigonal system space group P-31c with a=16.320(2),b=16.320(2),c=20.108(6)?,T=173(2) K,V=4638.2(16) A^(3),D_(c)=1.645 g/cm^(3),M_(r)=2297.33,Z=2,F(000)=2334,μ=0.970 mm~(–1),Goodness-of-fit=1.109,the final R=0.0776,wR=0.1813,Rindices (all data)=0.1196,wR=0.2011.The compound exhibits a triple-helical[Ag_(3)L_(3)]^(3+)crown-like trimer,in which three Ag(I) atoms form an equilateral triangle with the Ag···Ag distance of 4.7 A.Uncoordinated counterions ClO_(4)^(–) and solvent molecules methanol generate the hydrogen-bonded frameworks based on discrete molecular complex building blocks.展开更多
A mononuclear copper(II) complex CuL with a Schiff-base L (H2L = N,N(- cyclohexanebis(3-formyl-5-tert-butyl-salicylaldimine)) has been synthesized and characterized. X-ray diffraction analysis at room temperature indi...A mononuclear copper(II) complex CuL with a Schiff-base L (H2L = N,N(- cyclohexanebis(3-formyl-5-tert-butyl-salicylaldimine)) has been synthesized and characterized. X-ray diffraction analysis at room temperature indicates that the complex (Cu C30H36N2O4, Mr = 552.15) crystallizes in tetrahedral system, space group P41 with a = 13.4685(6), c = 31.326(2) ?, V = 5682.5(5) ?3, Z = 8, Dc = 1.291 g/cm3, F(000) = 4656, μ(MoK() = 0.805 mm-1. The final R and Rw factors are 0.0421 and 0.0815, respectively with 4435 observed reflections. The title complex is a neutral molecule in which the ligand is doubly deprotonated, forming a four-coordinated Cu(II) complex by nitrogen and oxygen donors of the ligand and the coordination geometry of Cu(II) could be considered as an approximately planar configuration. There are two independent molecules, having a transoid arrangement in this structure.展开更多
文摘Two new Zn(Ⅱ)-MOFs were synthesized based on an asymmetric Schiff-base ligand LH, which is obtained by the condensation of 5-formyl-8-hydroxyquinoline and 3-pyridinecar- boxylic acid hydrazide. In different mixed solvents, we get two new isomorphism compounds, [Zn(L)2]'CaHsO2-2MeOH (1) and [Zn(L)2]'CH2CIz'2MeOH (2). Compounds 1 and 2 have been characterized by single-crystal X-ray diffraction, elemental analysis and IR. Compound 1 crystallizes in monoclinic, space group P2/c, with a - 13.856(4), b = 14.156(4), c = 9.620(3)А, β = 110.167(5)°, V = 1771.3(9) /k3, Dc = 1.500 g/cm3, C3sH3sNsOsZn, Mr = 800.13, F(000) = 832, p(MoKa) = 0.761 mm-1, Z = 2, the final R = 0.0596 and wR = 0.1221 for 2112 observed reflections (I 〉 2σ(0). Compound 2 belongs to monoclinic, space group P21/c, with a = 13.575(3), b = 14.130(3), c = 9.485(2) A, β = 107.908(3)°, V= 1731.2(6) A3, Dc = 1.529 g/cm3, CasH32C12NsO6Zn, Mr = 796.96, F(000) = 820, g(MoKa) = 0.926 mm-1, Z = 2, the final R -- 0.0527 and wR = 0.1395 for 2501 observed reflections (I 〉 2σ-(/)). The Zn(II) centers in both 1 and 2 display a distorted octahedral coordination geometry. The octahedral Zn(lI) nodes and L linkages build up 2-D nets consisting of parallelogram-like grids in the ab plane. The neighboring nets stack through hydrogen bonds to generate 3-D rhombic channels. In 1, the 1,4-dioxane and MeOH guests alternatively arrange in the channels and effectively take up the free space; while in 2, the CH2CI/guests are arranged in the channels. In addition, the encapsulated MeOH molecules are bonded to the framework by hydrogen bonds.
文摘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.
基金financially supported by the National Natural Science Foundation of China(No.51569008)the Natural Science Foundation of Guangxi Province(No.2015GXNSFAA139240)Program for the Scientific Research and Guangxi Scientific Experiment Center of Mining,Metallurgy and Environment(No.KH2012ZD004)
文摘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.
基金the National Natural Science Foundation of China(Nos.20472026 and 20525206)Chang Jiang Scholar Program of the Ministry of Education, China.
文摘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.
基金supported by grants from NSFC(Nos.21671122 and 21475078)。
文摘One novel discrete coordination molecule with Ag^(I) centers,namely[Ag_(3)(L)_(3)(ClO_(4))_(3)]·3CH_(2)Cl_(2)·6CH_(3)OH·1.5H_(2)O (1),has been synthesized based on the double Schiff-base ligand,3,6-bis[2-(4-oxidequinoxaline)-yl]-4,5-diaza-3,5-octadiene (L) and AgClO_4.The obtained Ag(I) compound was fully characterized by infrared spectroscopy,elemental analysis,and single-crystal X-ray diffraction.1 is of trigonal system space group P-31c with a=16.320(2),b=16.320(2),c=20.108(6)?,T=173(2) K,V=4638.2(16) A^(3),D_(c)=1.645 g/cm^(3),M_(r)=2297.33,Z=2,F(000)=2334,μ=0.970 mm~(–1),Goodness-of-fit=1.109,the final R=0.0776,wR=0.1813,Rindices (all data)=0.1196,wR=0.2011.The compound exhibits a triple-helical[Ag_(3)L_(3)]^(3+)crown-like trimer,in which three Ag(I) atoms form an equilateral triangle with the Ag···Ag distance of 4.7 A.Uncoordinated counterions ClO_(4)^(–) and solvent molecules methanol generate the hydrogen-bonded frameworks based on discrete molecular complex building blocks.
基金the National Natural Science Foundation of China (No. 29871018) and the foundation of Open Laboratory for Chiral Technology of H
文摘A mononuclear copper(II) complex CuL with a Schiff-base L (H2L = N,N(- cyclohexanebis(3-formyl-5-tert-butyl-salicylaldimine)) has been synthesized and characterized. X-ray diffraction analysis at room temperature indicates that the complex (Cu C30H36N2O4, Mr = 552.15) crystallizes in tetrahedral system, space group P41 with a = 13.4685(6), c = 31.326(2) ?, V = 5682.5(5) ?3, Z = 8, Dc = 1.291 g/cm3, F(000) = 4656, μ(MoK() = 0.805 mm-1. The final R and Rw factors are 0.0421 and 0.0815, respectively with 4435 observed reflections. The title complex is a neutral molecule in which the ligand is doubly deprotonated, forming a four-coordinated Cu(II) complex by nitrogen and oxygen donors of the ligand and the coordination geometry of Cu(II) could be considered as an approximately planar configuration. There are two independent molecules, having a transoid arrangement in this structure.