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
Benzaldehyde has been trimethylsilylcyanated with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases. Cyanohydrin is obtalned in moderate e.e.values
Two new transition metal complexes based on chiral Schiff base ligand, namely Zn（L_1）_2（1） and Cd（L_2）2（2）（L 1=（R,E）-3-（2-hydroxy-3-methoxybenzylideneamino）propane-1,2-diol, L2=（R,E）-2-（（2-hydroxy-1-p...Two new transition metal complexes based on chiral Schiff base ligand, namely Zn（L_1）_2（1） and Cd（L_2）2（2）（L 1=（R,E）-3-（2-hydroxy-3-methoxybenzylideneamino）propane-1,2-diol, L2=（R,E）-2-（（2-hydroxy-1-phenylethylimino）methyl）-6-methoxyphenol）, have been synthesized and characterized. Single-crystal X-ray diffractions reveal that both 1 and 2 crystallize in the same monoclinic space group C_2. 1 is four-coordinated, while 2 is six-coordinated. Complexes 1 and 2 show fluorescent emission at 479 and 580 nm, respectively. Moreover, 1 and 2 exhibit selective and sensitive recognition toward Zn^（2＋）/Cd^（2＋） ions in the methanol solution.展开更多
Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO40.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and ma...Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO40.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and magnetic properties were determined and investigated. The H-bonding interactions concern just in neighbor cation and anion, do not extend into network for both 1 and 2. The temperature dependence of the magnetic susceptibilities (2-300K) showed that 1 is diamagnetism and 2 is paramagnetism with weak antiferromagnetic exchange interactions between adjacent spin carriers, no magnetic ordering taking place in these two complexes.展开更多
Two new Cu（Ⅱ） complexes have been synthesized with two different bidentate N2O2 donor Schiffbase ligands HL1 （2-（（E）-（4-chlorophenylimino）methyl）-6-bromo-4-chlorophenol） and HL2 （2-（（E）-（2-chlorophenyl...Two new Cu（Ⅱ） complexes have been synthesized with two different bidentate N2O2 donor Schiffbase ligands HL1 （2-（（E）-（4-chlorophenylimino）methyl）-6-bromo-4-chlorophenol） and HL2 （2-（（E）-（2-chlorophenylimino）methyl）-6-bromo-4-chlorophenol）, respectively. Both complexes 1 and 2 have been characterized by elemental analysis and single-crystal X-ray diffraction studies. Structural studies reveal that in both complexes the metal centers are four-coordinated with N202 donor set of Schiff base ligands. Complex 1 belongs to the tetragonal system, space group P4（3）2（1）2 with a = 10.2379（2）, b = 10.2379（2）, c = 24.9623（90） A, V = 2616.41（12） A^3, Z = 4, Dc = 1.908 g/cm^3,μ（MoKa） = 4.3327 mm^-1, F（000） = 1468, S = 0.999, the final R = 0.0345 and wR = 0.0835 for 3506 unique reflections （Rint= 0.0428） with 3249 observed ones （I 〉 2σ（I））. Complex 2 is of monoclinic system, space group P21/c with a = 11.064（3）, b = 9.437（2）, c = 13.277（4） A, fl = 108.997（3）°, V = 1310.8（6） A^3, Z = 2, Dc= 1.904 g/cm^3,μ（MoKa） = 4.319 mm^-1, F（000） = 734, S = 0.997, the final R = 0.0282 and wR = 0.0619 for 3491 unique reflections （Rint = 0.0428） with 2777 observed ones （I 〉 20（I））. The units of the complex are linked via weak interactions, such as C-H…Br hydrogen bonds together with Cl…C1 and Cu…Cl interactions, leading to the formation of one-dimensional chain and two-dimensional network and stabilizing the crystal structure.展开更多
The lanthanide complexes containing a bulky tridentate [N,N,O] Schiff base ligand 3,5-But2-2-（OH）C6H2CH=N-8-C9H6N （HL） were synthesized and characterized. The reaction of anhydrous LnCl3 with NaL formed in situ in...The lanthanide complexes containing a bulky tridentate [N,N,O] Schiff base ligand 3,5-But2-2-（OH）C6H2CH=N-8-C9H6N （HL） were synthesized and characterized. The reaction of anhydrous LnCl3 with NaL formed in situ in a 1：1 molar ratio in THF at room temperature afforded the lanthanide Schiff base dichloride complexes LnLCl2（DME） （Ln=Eu （1）; Sm （2））. Complexes 1 and 2 can be used as precursors for the synthesis of the lanthanide cyclopentadienyl Schiff base derivatives. The reactions of complexes 1 and 2 with one equiv of NaCH3C5H4 in THF provided the desired products LnL（CH3C5H4）CI（THF）.THF （Ln=Eu （3）; Sm （4）） in good isolated yields. These complexes were characterized by elemental analysis, IR spectra, and X-ray structural determination, in the case of complexes 3 and 4. The crystal data of complex 3 are monoclinic, P21/C space group, a=1.3370（2） nm, b=1.5190（2） nm, c=1.8910（3） nm, β=109.846（4）°, V=3.6125（8） nm^3, Z=4, Dc=1.416 mg/m^3,μ=1.847 mm^-1, F（000）=1584, R=0.0707, wR=0.1350. The crystal data of complex 4 are monoclinic, P21/c space group, a=1.3383（1） nm, b=1.5210（2） nm, c=1.8960（2） nm, β =109.878（3）°, V=3.6293（7） nm^3, Z=4, Dc=1.407 mg/m^3, μ=1.728 mm^-1, F（000）= 1580, R=0.0670, wR=0.1385.展开更多
Seven kinds of Schiff base metal complexes(C1-C7)were synthesized by the reaction of substituted salicylaldehyde Schiff base with cobalt nitrate,nickel nitrate,and copper nitrate,respectively.The oxygen carrying perfo...Seven kinds of Schiff base metal complexes(C1-C7)were synthesized by the reaction of substituted salicylaldehyde Schiff base with cobalt nitrate,nickel nitrate,and copper nitrate,respectively.The oxygen carrying performance,and the catalytic property of complexes for the oxidation of model sulfides 1-hexanethiol,dibutyl sulfide,and 2-methylthiophene along with their influencing factors were explored,while the oxidized products of the model sulfides were also analyzed and characterized.The results show that the catalytic oxidation property of the complexes is determined by their oxygen carrying performance and solubility in n-octane.The oxygen carrying performance of the complexes is mainly affected by the central ion species,the electronic effects,and the spatial effects of the substituents as well as the degree of conjugation.More specifically,the oxygen carrying performance can be improved by enhancing the oxygenation capacity of the central metal ions,increasing the electron donating ability of the ligand substituent,and diminishing the steric hindrance as well as extending the conjugated chain.Complexes C7 were found to be with high oxygen carrying capacity and high solubility in n-octane,which shows the best catalytic oxidation property,and the oxidation conversion rates for 1-hexylthiol,dibutyl sulfide,and 2-methylthiophene are 74.2%,65.1%,and 22.7%,respectively.Upon using the oxidation catalyst of Schiff base metal complexes,three sulfides can be oxidized by oxygen to form sulfones and sulfoxides.1-Hexanethiol and dibutyl sulfide will continue to be oxidized to form sulfates and sulfites.展开更多
The functionalized calix[4]pyrrole meso-substituted Schiff bases were conveniently prepared by four- step synthetic route. Furthermore, the nickel and copper complexes of calix[4]pyrrole meso-substituted Schiff base w...The functionalized calix[4]pyrrole meso-substituted Schiff bases were conveniently prepared by four- step synthetic route. Furthermore, the nickel and copper complexes of calix[4]pyrrole meso-substituted Schiff base with 1：2 stoichiometry were obtained. The crystal structures of the calix[4]pyrroles and their metal complexes were determined by X-ray diffraction.展开更多
Three novel Zn（II） complexes,[Zn4L1Cl4]-3H2O（1）,[Zn4L2Cl4]-2DMF（2） and[Zn4L^3Cl4]H2O（3）,have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic...Three novel Zn（II） complexes,[Zn4L1Cl4]-3H2O（1）,[Zn4L2Cl4]-2DMF（2） and[Zn4L^3Cl4]H2O（3）,have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by ＇2 ＋ 2＇ type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn（Ⅱ） complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn^2＋ sensors have been investigated.Take H4L^1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn^2＋ in MeOH.展开更多
Six new complexes of lanthanum with amino acid Schiff base ligands, A-F, were prepared in methanol-aqueous solution. The composition and properties of the title complexes were characterized by elemental analysis, mola...Six new complexes of lanthanum with amino acid Schiff base ligands, A-F, were prepared in methanol-aqueous solution. The composition and properties of the title complexes were characterized by elemental analysis, molar conductance, infrared, electronic spectra, H-1 NMR, thermogravimetric and differential thermal analysis.展开更多
The polymer-bound Schiff base ternary manganese complexes [PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ)] have been prepared from the polymer-bound Schiff base ligand, a manganese salt and the second ligand, such as 1,10-phena...The polymer-bound Schiff base ternary manganese complexes [PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ)] have been prepared from the polymer-bound Schiff base ligand, a manganese salt and the second ligand, such as 1,10-phenanthroline(phen), 2,2′-bipyridyl(bipy) and 8-quinolinol(8HQ). The polymer-bound Schiff base ternary manganese complexes were characterized by means of infrared spectrometry and ICP-AES. The catalytic activities of the complexes have been studied in the aerobic epoxidation of long-chain linear aliphatic olefins. It is shown that 1-octene or 1-decene can be directly oxidized by molecular oxygen when catalyzed by PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ), and 1,2-epoxy alkane can be afforded in these reactions.展开更多
<div style="text-align:justify;"> Herein we have originally designed chiral azo-salen Mn(II) and Zn(II) complexes for interacting silver nanoparticles (AgNPs) exhibiting localized surface plasmon reson...<div style="text-align:justify;"> Herein we have originally designed chiral azo-salen Mn(II) and Zn(II) complexes for interacting silver nanoparticles (AgNPs) exhibiting localized surface plasmon resonance (LSPR). Understanding excited state and reaction intermediate during light irradiation to return to ground state may be important for such composite systems. Therefore, we investigated such optical properties for systems using time-resolved luminescence and transient absorption measurements. DMSO solutions of the four newly prepared and characterized complexes (<strong>MMn</strong><strong>, MZn, CMn,</strong> and <strong>CZn</strong>) and ethanol solutions of the composite materials of each complex with AgNPs were served for optical measurements. The time-correlated single photon counting (TCSPC), the streak camera which is much shorter period of time than TCSPC and transient absorption measurement, was performed for the eight samples. The fluorescence lifetime of the sole complexes and the composite materials with AgNPs was derived from curve-fitting analysis of luminescence decay curves of TCSPC. Lifetime of the composite systems with AgNPs was longer than that of the corresponding sole metal complexes for three cases. It was revealed that composite systems may go through three reaction intermediates during relaxation from excited state to ground state. </div>展开更多
In this study,a novel class of histidine Schiff base silver（Ⅰ） complexes derived from salicylaldehyde,1a-9a,was found to be an effective inhibitor of α-glucosidase.The results of this study showed that the newly s...In this study,a novel class of histidine Schiff base silver（Ⅰ） complexes derived from salicylaldehyde,1a-9a,was found to be an effective inhibitor of α-glucosidase.The results of this study showed that the newly synthesized complexes inhibited α-glucosidase through noncompetitive mechanisms;the IC50values were ranging from 0.00431 μmol L ~1 to 0.492 μmol L ~1.The structure-activity relationship was established as well.These results demonstrated that compound 7a,5-nitro salicylaldehyde Schiff base silver complex,is the most promising α-glucosidase inhibitor with the lowest IC50 value,which could be exploited as a drug candidate to alleviate postprandial hyperglycemia in the treatment of type II diabetes mellitus.This research provided a catalyst-free,simple,and environmentally benign reaction to synthesize compounds using mechanochemistry.展开更多
Two new mononuclear complexes, namely [Co（L）2]（1） and [Mn（L）2]（2）（HL = N-（3-methylsalicylidene）tryptamine）, have been synthesized by the reactions of the ligand with cobalt acetate or manganese acetate in ...Two new mononuclear complexes, namely [Co（L）2]（1） and [Mn（L）2]（2）（HL = N-（3-methylsalicylidene）tryptamine）, have been synthesized by the reactions of the ligand with cobalt acetate or manganese acetate in anhydrous ethanol. The crystal structures of the complexes were characterized by IR spectrum, elemental analysis, PXRD and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in monoclinic, space group C2/c, with a = 23.146（2）, b = 9.4864（10）, c = 13.9261（15）A, β = 102.898（2）°, V = 2980.6（5） ？3, Z = 4, Dc = 1.367 g/cm3, F（000） = 1284 and μ = 0.616 mm^-1. Complex 2 crystallizes in monoclinic, space group P21/n, with a = 14.807（11）, b = 13.118（10）, c = 16.663（13） A, β = 111.237（14）°, V = 3017（4） A^3, Z = 4, Dc = 1.342 g/cm^3, F（000） = 1276 and μ = 0.477 mm-1. The units of complex 1 are linked by intermolecular N–H…π hydrogen bonds into infinite 1D chains, which are further extended into a 3D supramolecular structure by a series of π···π stacking interactions. The units of complex 2 are linked by intermolecular N–H…π hydrogen bonds and C–H…π hydrogen bonds into an infinite 3D supramolecular structure. Meanwhile, the antibacterial activities of the ligand and its complexes have been tested against four kinds of bacteria. The results show that the three compounds all have excellent antibacterial activities and that 1 and 2 possess stronger inhibiting effects against the bacteria than the Schiff base.展开更多
Some new Schiff bases were synthesized by the condensation of equimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine or its derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3...Some new Schiff bases were synthesized by the condensation of equimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine or its derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3 where M=Cu^(2+),Co^(2+),Ni^(2+),Mn^(2+)Pd^(2+),M'=Fe^(3+)and L=different newly synthesized monobasic Schiff bases were prepared in absolute ethanolic medium(2)and characterized by elementary analysis,conductance measurements,infrared spectra,electronic spectra,magnetic moments studies.展开更多
In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and ...In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and characterized.展开更多
Schiff base-Cu（II） complex is found to be an effective catalyst for the condensation reaction of indole with aldehydes using ethanol as the solvent. The characterization of the catalysts was carried out using XRD an...Schiff base-Cu（II） complex is found to be an effective catalyst for the condensation reaction of indole with aldehydes using ethanol as the solvent. The characterization of the catalysts was carried out using XRD and FT-IR.展开更多
A silica gel supported cobalt（lI） Schiff base complex was synthesized and used for the oxidation of alkyl aromatics using molecular oxygen as an oxidant under atmosphere pressure. The catalyst shows a high conversio...A silica gel supported cobalt（lI） Schiff base complex was synthesized and used for the oxidation of alkyl aromatics using molecular oxygen as an oxidant under atmosphere pressure. The catalyst shows a high conversion of alkyl aromatics and selectivity to benzylic ketones, and could be reused at least 5 times without significant loss of catalytic activity.展开更多
A new chain-like coordination polymer, namely, [CuL]n （1, Na2L = 2-[（2-hydroxy- benzylidene）-amino]-benzenesulfonic acid sodium salt）, has been synthesized and characterized by single-crystal X-ray diffraction, IR...A new chain-like coordination polymer, namely, [CuL]n （1, Na2L = 2-[（2-hydroxy- benzylidene）-amino]-benzenesulfonic acid sodium salt）, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analysis. Complex 1 crystallizes in monoclinic system, space group P21/c with a = 9.2296（16）, b = 10.4754（18）, c = 12.200（2） A, β = 102.392（2）°, V = 1152.0（3）A3, CI3H9CuNOaN, Mr = 338.83, Dc = 1.953 g/cm3, Z = 4, F（000） = 684, p = 2.089 mm-1, the final R = 0.0376 and wR = 0.0956. X-ray diffraction analyses indicate that 1 displays a square-pyramidal metal center with NO4 donor sets. The sulfonate-derived Schiff base serves as a common N,O,O＇-tridentate and a unique O-bridged ligand connecting the metals. Dinuclear copper complexes serve as secondary building blocks （SBUs） to construct an unusual 2D coordination network. In the crystal, the components form a stable 3D supramolecular architecture by C-H...O interactions and to-stacking展开更多
文摘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
文摘Benzaldehyde has been trimethylsilylcyanated with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases. Cyanohydrin is obtalned in moderate e.e.values
基金supported by the National Natural Science Foundation of China(21101090 and 21561021)the Natural Science Foundation of Jiangxi Province(20114BAB213001)the Education Department of Jiangxi Province(GJJ12041)
文摘Two new transition metal complexes based on chiral Schiff base ligand, namely Zn（L_1）_2（1） and Cd（L_2）2（2）（L 1=（R,E）-3-（2-hydroxy-3-methoxybenzylideneamino）propane-1,2-diol, L2=（R,E）-2-（（2-hydroxy-1-phenylethylimino）methyl）-6-methoxyphenol）, have been synthesized and characterized. Single-crystal X-ray diffractions reveal that both 1 and 2 crystallize in the same monoclinic space group C_2. 1 is four-coordinated, while 2 is six-coordinated. Complexes 1 and 2 show fluorescent emission at 479 and 580 nm, respectively. Moreover, 1 and 2 exhibit selective and sensitive recognition toward Zn^（2＋）/Cd^（2＋） ions in the methanol solution.
文摘Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO40.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and magnetic properties were determined and investigated. The H-bonding interactions concern just in neighbor cation and anion, do not extend into network for both 1 and 2. The temperature dependence of the magnetic susceptibilities (2-300K) showed that 1 is diamagnetism and 2 is paramagnetism with weak antiferromagnetic exchange interactions between adjacent spin carriers, no magnetic ordering taking place in these two complexes.
基金Project supported by the research grant of Phytochemistry Key Laboratory of Shaanxi Province (No. 12JS007)
文摘Two new Cu（Ⅱ） complexes have been synthesized with two different bidentate N2O2 donor Schiffbase ligands HL1 （2-（（E）-（4-chlorophenylimino）methyl）-6-bromo-4-chlorophenol） and HL2 （2-（（E）-（2-chlorophenylimino）methyl）-6-bromo-4-chlorophenol）, respectively. Both complexes 1 and 2 have been characterized by elemental analysis and single-crystal X-ray diffraction studies. Structural studies reveal that in both complexes the metal centers are four-coordinated with N202 donor set of Schiff base ligands. Complex 1 belongs to the tetragonal system, space group P4（3）2（1）2 with a = 10.2379（2）, b = 10.2379（2）, c = 24.9623（90） A, V = 2616.41（12） A^3, Z = 4, Dc = 1.908 g/cm^3,μ（MoKa） = 4.3327 mm^-1, F（000） = 1468, S = 0.999, the final R = 0.0345 and wR = 0.0835 for 3506 unique reflections （Rint= 0.0428） with 3249 observed ones （I 〉 2σ（I））. Complex 2 is of monoclinic system, space group P21/c with a = 11.064（3）, b = 9.437（2）, c = 13.277（4） A, fl = 108.997（3）°, V = 1310.8（6） A^3, Z = 2, Dc= 1.904 g/cm^3,μ（MoKa） = 4.319 mm^-1, F（000） = 734, S = 0.997, the final R = 0.0282 and wR = 0.0619 for 3491 unique reflections （Rint = 0.0428） with 2777 observed ones （I 〉 20（I））. The units of the complex are linked via weak interactions, such as C-H…Br hydrogen bonds together with Cl…C1 and Cu…Cl interactions, leading to the formation of one-dimensional chain and two-dimensional network and stabilizing the crystal structure.
基金the National Natural Science Foundation of Chinathe Natural Science Foundation of Jiangsu Province (BK2007505)Major Basic Research Project of the Natural Science Foundation of the Jiangsu Higher Education Institutions (07KJA15014)
文摘The lanthanide complexes containing a bulky tridentate [N,N,O] Schiff base ligand 3,5-But2-2-（OH）C6H2CH=N-8-C9H6N （HL） were synthesized and characterized. The reaction of anhydrous LnCl3 with NaL formed in situ in a 1：1 molar ratio in THF at room temperature afforded the lanthanide Schiff base dichloride complexes LnLCl2（DME） （Ln=Eu （1）; Sm （2））. Complexes 1 and 2 can be used as precursors for the synthesis of the lanthanide cyclopentadienyl Schiff base derivatives. The reactions of complexes 1 and 2 with one equiv of NaCH3C5H4 in THF provided the desired products LnL（CH3C5H4）CI（THF）.THF （Ln=Eu （3）; Sm （4）） in good isolated yields. These complexes were characterized by elemental analysis, IR spectra, and X-ray structural determination, in the case of complexes 3 and 4. The crystal data of complex 3 are monoclinic, P21/C space group, a=1.3370（2） nm, b=1.5190（2） nm, c=1.8910（3） nm, β=109.846（4）°, V=3.6125（8） nm^3, Z=4, Dc=1.416 mg/m^3,μ=1.847 mm^-1, F（000）=1584, R=0.0707, wR=0.1350. The crystal data of complex 4 are monoclinic, P21/c space group, a=1.3383（1） nm, b=1.5210（2） nm, c=1.8960（2） nm, β =109.878（3）°, V=3.6293（7） nm^3, Z=4, Dc=1.407 mg/m^3, μ=1.728 mm^-1, F（000）= 1580, R=0.0670, wR=0.1385.
基金This work was supported by the National Natural Science Foundation of China(No.21576292).
文摘Seven kinds of Schiff base metal complexes(C1-C7)were synthesized by the reaction of substituted salicylaldehyde Schiff base with cobalt nitrate,nickel nitrate,and copper nitrate,respectively.The oxygen carrying performance,and the catalytic property of complexes for the oxidation of model sulfides 1-hexanethiol,dibutyl sulfide,and 2-methylthiophene along with their influencing factors were explored,while the oxidized products of the model sulfides were also analyzed and characterized.The results show that the catalytic oxidation property of the complexes is determined by their oxygen carrying performance and solubility in n-octane.The oxygen carrying performance of the complexes is mainly affected by the central ion species,the electronic effects,and the spatial effects of the substituents as well as the degree of conjugation.More specifically,the oxygen carrying performance can be improved by enhancing the oxygenation capacity of the central metal ions,increasing the electron donating ability of the ligand substituent,and diminishing the steric hindrance as well as extending the conjugated chain.Complexes C7 were found to be with high oxygen carrying capacity and high solubility in n-octane,which shows the best catalytic oxidation property,and the oxidation conversion rates for 1-hexylthiol,dibutyl sulfide,and 2-methylthiophene are 74.2%,65.1%,and 22.7%,respectively.Upon using the oxidation catalyst of Schiff base metal complexes,three sulfides can be oxidized by oxygen to form sulfones and sulfoxides.1-Hexanethiol and dibutyl sulfide will continue to be oxidized to form sulfates and sulfites.
基金financially supported by the National Natural Science Foundation of China (No.21172190)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The functionalized calix[4]pyrrole meso-substituted Schiff bases were conveniently prepared by four- step synthetic route. Furthermore, the nickel and copper complexes of calix[4]pyrrole meso-substituted Schiff base with 1：2 stoichiometry were obtained. The crystal structures of the calix[4]pyrroles and their metal complexes were determined by X-ray diffraction.
基金financially supported by NSFC,the Program for Professor of Special Appointment(Eastern Scholar) at Shanghai Institutions of Higher Learning,Program for New Century Excellent Talents in University(No.NCET-11-0638)Innovation Program of Shanghai Municipal Education Commission,the Fundamental Research Funds for the Central Universities(No.WK1013002)+1 种基金SRFDP(No.20100074110015)S.W.Ng is grateful for support by the University of Malaya(No.UM.C/625/1/H1R/033/10)
文摘Three novel Zn（II） complexes,[Zn4L1Cl4]-3H2O（1）,[Zn4L2Cl4]-2DMF（2） and[Zn4L^3Cl4]H2O（3）,have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by ＇2 ＋ 2＇ type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn（Ⅱ） complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn^2＋ sensors have been investigated.Take H4L^1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn^2＋ in MeOH.
文摘Six new complexes of lanthanum with amino acid Schiff base ligands, A-F, were prepared in methanol-aqueous solution. The composition and properties of the title complexes were characterized by elemental analysis, molar conductance, infrared, electronic spectra, H-1 NMR, thermogravimetric and differential thermal analysis.
基金Supported by the National Natural Science Foundation of China(No.2 99330 5 0,2 95 74 176 ,2 0 2 74 0 34)
文摘The polymer-bound Schiff base ternary manganese complexes [PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ)] have been prepared from the polymer-bound Schiff base ligand, a manganese salt and the second ligand, such as 1,10-phenanthroline(phen), 2,2′-bipyridyl(bipy) and 8-quinolinol(8HQ). The polymer-bound Schiff base ternary manganese complexes were characterized by means of infrared spectrometry and ICP-AES. The catalytic activities of the complexes have been studied in the aerobic epoxidation of long-chain linear aliphatic olefins. It is shown that 1-octene or 1-decene can be directly oxidized by molecular oxygen when catalyzed by PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ), and 1,2-epoxy alkane can be afforded in these reactions.
文摘<div style="text-align:justify;"> Herein we have originally designed chiral azo-salen Mn(II) and Zn(II) complexes for interacting silver nanoparticles (AgNPs) exhibiting localized surface plasmon resonance (LSPR). Understanding excited state and reaction intermediate during light irradiation to return to ground state may be important for such composite systems. Therefore, we investigated such optical properties for systems using time-resolved luminescence and transient absorption measurements. DMSO solutions of the four newly prepared and characterized complexes (<strong>MMn</strong><strong>, MZn, CMn,</strong> and <strong>CZn</strong>) and ethanol solutions of the composite materials of each complex with AgNPs were served for optical measurements. The time-correlated single photon counting (TCSPC), the streak camera which is much shorter period of time than TCSPC and transient absorption measurement, was performed for the eight samples. The fluorescence lifetime of the sole complexes and the composite materials with AgNPs was derived from curve-fitting analysis of luminescence decay curves of TCSPC. Lifetime of the composite systems with AgNPs was longer than that of the corresponding sole metal complexes for three cases. It was revealed that composite systems may go through three reaction intermediates during relaxation from excited state to ground state. </div>
文摘In this study,a novel class of histidine Schiff base silver（Ⅰ） complexes derived from salicylaldehyde,1a-9a,was found to be an effective inhibitor of α-glucosidase.The results of this study showed that the newly synthesized complexes inhibited α-glucosidase through noncompetitive mechanisms;the IC50values were ranging from 0.00431 μmol L ~1 to 0.492 μmol L ~1.The structure-activity relationship was established as well.These results demonstrated that compound 7a,5-nitro salicylaldehyde Schiff base silver complex,is the most promising α-glucosidase inhibitor with the lowest IC50 value,which could be exploited as a drug candidate to alleviate postprandial hyperglycemia in the treatment of type II diabetes mellitus.This research provided a catalyst-free,simple,and environmentally benign reaction to synthesize compounds using mechanochemistry.
基金supported by the National Natural Science Foundation of China(No.21272008)the Natural Science Industry-University-Research Foundation of Suzhou University(2015hx014)
文摘Two new mononuclear complexes, namely [Co（L）2]（1） and [Mn（L）2]（2）（HL = N-（3-methylsalicylidene）tryptamine）, have been synthesized by the reactions of the ligand with cobalt acetate or manganese acetate in anhydrous ethanol. The crystal structures of the complexes were characterized by IR spectrum, elemental analysis, PXRD and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in monoclinic, space group C2/c, with a = 23.146（2）, b = 9.4864（10）, c = 13.9261（15）A, β = 102.898（2）°, V = 2980.6（5） ？3, Z = 4, Dc = 1.367 g/cm3, F（000） = 1284 and μ = 0.616 mm^-1. Complex 2 crystallizes in monoclinic, space group P21/n, with a = 14.807（11）, b = 13.118（10）, c = 16.663（13） A, β = 111.237（14）°, V = 3017（4） A^3, Z = 4, Dc = 1.342 g/cm^3, F（000） = 1276 and μ = 0.477 mm-1. The units of complex 1 are linked by intermolecular N–H…π hydrogen bonds into infinite 1D chains, which are further extended into a 3D supramolecular structure by a series of π···π stacking interactions. The units of complex 2 are linked by intermolecular N–H…π hydrogen bonds and C–H…π hydrogen bonds into an infinite 3D supramolecular structure. Meanwhile, the antibacterial activities of the ligand and its complexes have been tested against four kinds of bacteria. The results show that the three compounds all have excellent antibacterial activities and that 1 and 2 possess stronger inhibiting effects against the bacteria than the Schiff base.
文摘Some new Schiff bases were synthesized by the condensation of equimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine or its derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3 where M=Cu^(2+),Co^(2+),Ni^(2+),Mn^(2+)Pd^(2+),M'=Fe^(3+)and L=different newly synthesized monobasic Schiff bases were prepared in absolute ethanolic medium(2)and characterized by elementary analysis,conductance measurements,infrared spectra,electronic spectra,magnetic moments studies.
基金National Natural Science Foundation of China for financial support of this work
文摘In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and characterized.
基金support from the National Natural Science Foundation of China(Nos.20962018, 20862015,20762009 and 20562011)
文摘Schiff base-Cu（II） complex is found to be an effective catalyst for the condensation reaction of indole with aldehydes using ethanol as the solvent. The characterization of the catalysts was carried out using XRD and FT-IR.
基金the financial support from the National Natural Science Foundation of China–Academy of Engineering Physics(No.10976014)Natural Science Foundation of Jiangsu Province(No.BK2011697)
文摘A silica gel supported cobalt（lI） Schiff base complex was synthesized and used for the oxidation of alkyl aromatics using molecular oxygen as an oxidant under atmosphere pressure. The catalyst shows a high conversion of alkyl aromatics and selectivity to benzylic ketones, and could be reused at least 5 times without significant loss of catalytic activity.
基金Supported by Guangxi Provincial Department of Education(No.YB2014333)the Scientific research and technological development project of Guilin(No.20110330)+2 种基金the Project of Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources(Guangxi Normal University)Ministry of Education of China(CMEMR2011-13)Key Subjects of Universities in Guangxi Province Applied Chemistry(2007<20>)
文摘A new chain-like coordination polymer, namely, [CuL]n （1, Na2L = 2-[（2-hydroxy- benzylidene）-amino]-benzenesulfonic acid sodium salt）, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analysis. Complex 1 crystallizes in monoclinic system, space group P21/c with a = 9.2296（16）, b = 10.4754（18）, c = 12.200（2） A, β = 102.392（2）°, V = 1152.0（3）A3, CI3H9CuNOaN, Mr = 338.83, Dc = 1.953 g/cm3, Z = 4, F（000） = 684, p = 2.089 mm-1, the final R = 0.0376 and wR = 0.0956. X-ray diffraction analyses indicate that 1 displays a square-pyramidal metal center with NO4 donor sets. The sulfonate-derived Schiff base serves as a common N,O,O＇-tridentate and a unique O-bridged ligand connecting the metals. Dinuclear copper complexes serve as secondary building blocks （SBUs） to construct an unusual 2D coordination network. In the crystal, the components form a stable 3D supramolecular architecture by C-H...O interactions and to-stacking
