Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mon...Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mononuclear complex due to the difference of their electronegativities,and coordination capabilities.Herein,we report a novel sulfur-phosphine co-coordinated heterogeneous Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)&S),which exhibits an unexpected 1.5–2.0 times catalytic activity for hydroformylation of olefins(C_(3)=,C_(5)=–C_(8)=),in comparison with the solely phosphine-coordinated Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)).In contrast,sulfur coordination alone leads to severe sulfur poisoning with significantly inhibited catalytic performance.Experimental and theoretical analyses reveal that phosphine coordination promotes catalytic activity via its strong electron-donating ability,while sulfur occupies a coordination site and reduces the electronic density of Rh ions.The synergistical coordination of sulfur and phosphine optimizes the electronic density of active Rh ions and decreases the energy barrier of the rate-determining step of olefin insertion,thus enhancing the hydroformylation activity,regioselectivity and stability of Rh_(1)/POPs-PPh_(3)&S.展开更多
The mononuclear macrocyclic polyamine metal complexes 5a-5e have been shown to form stable 1:1 complexes with bases and nucleosides. Their binding constants (K) were determined by UV-visible spectrometric titration. T...The mononuclear macrocyclic polyamine metal complexes 5a-5e have been shown to form stable 1:1 complexes with bases and nucleosides. Their binding constants (K) were determined by UV-visible spectrometric titration. The results show that recognition ability of the complexes 5a-5e for uracil, U (Uri-dine), dT (Thymidine) is higher than that for the other bases or nucleosides (such as Cytidine, Guanosine, Adenosine). The metal ion also plays an important role for the recognition ability of complexes.展开更多
Two hydrazone ligands （E）-N＇-（2-hydroxy-5-methoxybenzylidene）-2-hydroxybenzo- hydrazide （HLa） and （E）-N＇-（3,5-dichloro-2- hydroxybenzylidene）-4-methoxybenzohydrazide （HLb） were prepared and characterized...Two hydrazone ligands （E）-N＇-（2-hydroxy-5-methoxybenzylidene）-2-hydroxybenzo- hydrazide （HLa） and （E）-N＇-（3,5-dichloro-2- hydroxybenzylidene）-4-methoxybenzohydrazide （HLb） were prepared and characterized by IR, UV-Vis and 1H NMR spectra. Based on the hydrazone ligands, two new structurally similar vanadium（V） complexes, [VOLaL].CH3OH （1） and [vOLbL] （2）, where L is the monoanionic form of benzohydroxamic acid （HL）, were prepared and characterized by IR and UV-Vis spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes as the monoclinic space group P21/n, with a = 7.5208（10）, b = 15.490（2）, c = 20.8929（18） A, β = 96.373（2）°, V = 2418.9（5） A3, Z = 4, R = 0.0831, wR = 0.2607 and GOOF = 1.061. Complex 2 crystallizes as the monoclinic space group P21/c, with a = 11.8577（18）, b = 16.468（2）, c = 12.2288（18） A, β = 106.064（2）°, V= 2294.7（6） A3, Z = 4, R= 0.0741, wR= 0.1745 and GOOF= 1.014. X-ray analysis indicates that the complexes are mononuclear vanadium （V） species, with the V atoms located in the octahedral coordination. The hydrazone ligands and the complexes were evaluated for their antibacterial （Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescence） and antifungal （Candida albicans and Aspergillus niger） activities by MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide） method.展开更多
The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N＇,N＇-tetrakis（2-（p-tolylsulfonyl）aminoethyl） propane-1,2-diamine. The mononuclear copper（Ⅱ） com...The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N＇,N＇-tetrakis（2-（p-tolylsulfonyl）aminoethyl） propane-1,2-diamine. The mononuclear copper（Ⅱ） complex, [CuLH2O]·H2O, was synthesized by the reaction between the intermediate and copper（Ⅱ） in absolute methanol. The complex has been characterized by IR, UV-vis and X-ray diffraction technology, and its crystal crystallizes in the orthorhombic system, space group Pbca with a = 15.589（1）, b = 21.897（2）, c = 27.645（2） A, V = 9436.4（1）A^3, Dc = 1.352 g/cm^3, Z = 8, Mr = 960.68, F（000） = 4040, μ（MoKa） = 0.698 mm-1, S = 0.98, R = 0.0537 and wR = 0.1180 for 5804 observed reflections （I 〉 2σ（I））. In the crystal structure, a one-dimensional chain is formed by abundant hydrogen bond interactions. The interaction of the complex with DNA was monitored using agarose gel electrophoresis. The result shows that the complex can transform the supercoiled to nicked and liner forms, and has a concentration-dependent cleavage activity.展开更多
The stability constants of the mononuclear complexes of BDBPH-Zn(II), Cd(II) and Mn (II) were determined by the potentiometric equilibrium measurements, and species distributions were also discussed. The metal ions do...The stability constants of the mononuclear complexes of BDBPH-Zn(II), Cd(II) and Mn (II) were determined by the potentiometric equilibrium measurements, and species distributions were also discussed. The metal ions do not combine with the ligand until the first two protons of the ligand have almost been completely neutralized. The main species were mononuclear complexes with the diprotonated ligand, MH,L. The three metal ions also form mono- and noprotonated (fully deprotonated) complexes, MHL, ML. The relative order of stabilities of the mononuclear complexes, ML, is Zn(II) > Cd(II) > Mn(II). The ligand has strong tendency to form mononuclear complexes with Zn(II), Cd(II) and Mn(II), and it can also form dinuclear complexes at high pH.展开更多
The mixed complex [Ni（L）（L＇）]（ClO4）2 has been synthesized using 2-aminoethyl- bi（3-bi-aminopropyl）amine with phen （1,10-phenanthroline） in the presence of Ni（Ⅱ） ion, and its structure was determined by X...The mixed complex [Ni（L）（L＇）]（ClO4）2 has been synthesized using 2-aminoethyl- bi（3-bi-aminopropyl）amine with phen （1,10-phenanthroline） in the presence of Ni（Ⅱ） ion, and its structure was determined by X-ray diffraction. The crystal crystallizes in monoclinic, space group P21/c with a = 13.713（2）, b = 13.1466（19）, c = 14.780（2） A°, β= 97.620（3）°, V = 2640.9（7） A °^3, F（000） = 1272, Z = 4, Dc = 1.540 g/cm^3, R = 0.0536 and wR = 0.1207. The Ni^2＋ ion is sixcoordinated to furnish a distorted octahedral geometry.展开更多
Schiff base ligand （HL） derived from 4-hexylaniline with isatin （1H-indole-2,3-dione） and its complexes with Cu（Ⅱ）, Ni（Ⅱ） were prepared and characterized by analytical, spectroscopic （IR, UV-Vis, Mass） tec...Schiff base ligand （HL） derived from 4-hexylaniline with isatin （1H-indole-2,3-dione） and its complexes with Cu（Ⅱ）, Ni（Ⅱ） were prepared and characterized by analytical, spectroscopic （IR, UV-Vis, Mass） techniques, electrical conductivity, magnetic and thermal measurements. The crystal and molecular structure of [Cu（HL）2Cl2] was determined by a single-crystal X-ray diffraction study. The molecular structure of the title compound has an inversion center on the Cu atom.展开更多
A three-coordinate Ag（I） complex, [Ag（Mepzpy）（PAr3）]BF4·H2O（1, Mepzpy = 3-methyl-1-（2-pyridyl）pyrazole, PAr3 = tri（o-tolyl）phosphine）, was synthesized from the reaction of Ag（CH3CN）4BF4, PAr3 and Me...A three-coordinate Ag（I） complex, [Ag（Mepzpy）（PAr3）]BF4·H2O（1, Mepzpy = 3-methyl-1-（2-pyridyl）pyrazole, PAr3 = tri（o-tolyl）phosphine）, was synthesized from the reaction of Ag（CH3CN）4BF4, PAr3 and Mepzpy in CH3 CN at room temperature. The compound was characterized by UV-vis, NMR and X-ray single-crystal structure analysis. It crystallizes in triclinic space group P1 with a = 10.2251（5）, b = 10.6014（5）, c = 15.7012（5） A, α = 92.963（3）, β = 92.641（3）, γ = 114.647（4）°, V = 1540.6（1）A 3, Z = 2, Mr = 676.24, Dc = 1.458 g/cm3, F（000） = 688, μ = 6.187 mm^-1, GOOF = 1.038, the final R = 0.0530 and wR = 0.1493 for 6371 observed reflections with I 〉 2σ（I）. Compound 1 is ionic. It is composed of a BF4- anion and a [Ag（Mepzpy）（PAr3）]＋ cation. The Ag（I） ion adopts a distorted trigonal pyramidal coordination geometry defined by two nitrogen atoms and a phosphorous atom. The complex emits blue luminescence with maximum peaks at 470 nm in solid state at room temperature.展开更多
文摘Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mononuclear complex due to the difference of their electronegativities,and coordination capabilities.Herein,we report a novel sulfur-phosphine co-coordinated heterogeneous Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)&S),which exhibits an unexpected 1.5–2.0 times catalytic activity for hydroformylation of olefins(C_(3)=,C_(5)=–C_(8)=),in comparison with the solely phosphine-coordinated Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)).In contrast,sulfur coordination alone leads to severe sulfur poisoning with significantly inhibited catalytic performance.Experimental and theoretical analyses reveal that phosphine coordination promotes catalytic activity via its strong electron-donating ability,while sulfur occupies a coordination site and reduces the electronic density of Rh ions.The synergistical coordination of sulfur and phosphine optimizes the electronic density of active Rh ions and decreases the energy barrier of the rate-determining step of olefin insertion,thus enhancing the hydroformylation activity,regioselectivity and stability of Rh_(1)/POPs-PPh_(3)&S.
基金Project supported by the National Natural Science Foundation of China(No.20132020)and Doctoral Foundation from National Educational Committee for Financial support.
文摘The mononuclear macrocyclic polyamine metal complexes 5a-5e have been shown to form stable 1:1 complexes with bases and nucleosides. Their binding constants (K) were determined by UV-visible spectrometric titration. The results show that recognition ability of the complexes 5a-5e for uracil, U (Uri-dine), dT (Thymidine) is higher than that for the other bases or nucleosides (such as Cytidine, Guanosine, Adenosine). The metal ion also plays an important role for the recognition ability of complexes.
基金the Educational Commission of Henan Province (No. 14B150036)the Natural Science Foundation of Henan Province (No. 142300410252)the Key Disciplines of Analytical Chemistry of Henan Province
文摘Two hydrazone ligands （E）-N＇-（2-hydroxy-5-methoxybenzylidene）-2-hydroxybenzo- hydrazide （HLa） and （E）-N＇-（3,5-dichloro-2- hydroxybenzylidene）-4-methoxybenzohydrazide （HLb） were prepared and characterized by IR, UV-Vis and 1H NMR spectra. Based on the hydrazone ligands, two new structurally similar vanadium（V） complexes, [VOLaL].CH3OH （1） and [vOLbL] （2）, where L is the monoanionic form of benzohydroxamic acid （HL）, were prepared and characterized by IR and UV-Vis spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes as the monoclinic space group P21/n, with a = 7.5208（10）, b = 15.490（2）, c = 20.8929（18） A, β = 96.373（2）°, V = 2418.9（5） A3, Z = 4, R = 0.0831, wR = 0.2607 and GOOF = 1.061. Complex 2 crystallizes as the monoclinic space group P21/c, with a = 11.8577（18）, b = 16.468（2）, c = 12.2288（18） A, β = 106.064（2）°, V= 2294.7（6） A3, Z = 4, R= 0.0741, wR= 0.1745 and GOOF= 1.014. X-ray analysis indicates that the complexes are mononuclear vanadium （V） species, with the V atoms located in the octahedral coordination. The hydrazone ligands and the complexes were evaluated for their antibacterial （Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescence） and antifungal （Candida albicans and Aspergillus niger） activities by MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide） method.
基金Supported by the National Natural Science Foundation of China (No. 20871097)the Foundation of the Innovative Group of the Education Department of Hubei Province (No. T200802)the Natural Science Foundation of the Science & Technology Department of Hubei Province (No. 2008CDB022)
文摘The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N＇,N＇-tetrakis（2-（p-tolylsulfonyl）aminoethyl） propane-1,2-diamine. The mononuclear copper（Ⅱ） complex, [CuLH2O]·H2O, was synthesized by the reaction between the intermediate and copper（Ⅱ） in absolute methanol. The complex has been characterized by IR, UV-vis and X-ray diffraction technology, and its crystal crystallizes in the orthorhombic system, space group Pbca with a = 15.589（1）, b = 21.897（2）, c = 27.645（2） A, V = 9436.4（1）A^3, Dc = 1.352 g/cm^3, Z = 8, Mr = 960.68, F（000） = 4040, μ（MoKa） = 0.698 mm-1, S = 0.98, R = 0.0537 and wR = 0.1180 for 5804 observed reflections （I 〉 2σ（I））. In the crystal structure, a one-dimensional chain is formed by abundant hydrogen bond interactions. The interaction of the complex with DNA was monitored using agarose gel electrophoresis. The result shows that the complex can transform the supercoiled to nicked and liner forms, and has a concentration-dependent cleavage activity.
基金The financial support from the Robert A. Welch Foundation (A-0259) in the U.S and China Scholarship Council (97837086) is gratefully acknowledged.
文摘The stability constants of the mononuclear complexes of BDBPH-Zn(II), Cd(II) and Mn (II) were determined by the potentiometric equilibrium measurements, and species distributions were also discussed. The metal ions do not combine with the ligand until the first two protons of the ligand have almost been completely neutralized. The main species were mononuclear complexes with the diprotonated ligand, MH,L. The three metal ions also form mono- and noprotonated (fully deprotonated) complexes, MHL, ML. The relative order of stabilities of the mononuclear complexes, ML, is Zn(II) > Cd(II) > Mn(II). The ligand has strong tendency to form mononuclear complexes with Zn(II), Cd(II) and Mn(II), and it can also form dinuclear complexes at high pH.
基金This project was supported by the National Natural Science Foundation of China (No. 50372028) and the Foundation of hhit Marine-Technology lab.
文摘The mixed complex [Ni（L）（L＇）]（ClO4）2 has been synthesized using 2-aminoethyl- bi（3-bi-aminopropyl）amine with phen （1,10-phenanthroline） in the presence of Ni（Ⅱ） ion, and its structure was determined by X-ray diffraction. The crystal crystallizes in monoclinic, space group P21/c with a = 13.713（2）, b = 13.1466（19）, c = 14.780（2） A°, β= 97.620（3）°, V = 2640.9（7） A °^3, F（000） = 1272, Z = 4, Dc = 1.540 g/cm^3, R = 0.0536 and wR = 0.1207. The Ni^2＋ ion is sixcoordinated to furnish a distorted octahedral geometry.
文摘Schiff base ligand （HL） derived from 4-hexylaniline with isatin （1H-indole-2,3-dione） and its complexes with Cu（Ⅱ）, Ni（Ⅱ） were prepared and characterized by analytical, spectroscopic （IR, UV-Vis, Mass） techniques, electrical conductivity, magnetic and thermal measurements. The crystal and molecular structure of [Cu（HL）2Cl2] was determined by a single-crystal X-ray diffraction study. The molecular structure of the title compound has an inversion center on the Cu atom.
基金supported by the National Natural Science Foundation of China(51172232)
文摘A three-coordinate Ag（I） complex, [Ag（Mepzpy）（PAr3）]BF4·H2O（1, Mepzpy = 3-methyl-1-（2-pyridyl）pyrazole, PAr3 = tri（o-tolyl）phosphine）, was synthesized from the reaction of Ag（CH3CN）4BF4, PAr3 and Mepzpy in CH3 CN at room temperature. The compound was characterized by UV-vis, NMR and X-ray single-crystal structure analysis. It crystallizes in triclinic space group P1 with a = 10.2251（5）, b = 10.6014（5）, c = 15.7012（5） A, α = 92.963（3）, β = 92.641（3）, γ = 114.647（4）°, V = 1540.6（1）A 3, Z = 2, Mr = 676.24, Dc = 1.458 g/cm3, F（000） = 688, μ = 6.187 mm^-1, GOOF = 1.038, the final R = 0.0530 and wR = 0.1493 for 6371 observed reflections with I 〉 2σ（I）. Compound 1 is ionic. It is composed of a BF4- anion and a [Ag（Mepzpy）（PAr3）]＋ cation. The Ag（I） ion adopts a distorted trigonal pyramidal coordination geometry defined by two nitrogen atoms and a phosphorous atom. The complex emits blue luminescence with maximum peaks at 470 nm in solid state at room temperature.
