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
<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
An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di(t-butyl) substituted derivatives with corresponding d...An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di(t-butyl) substituted derivatives with corresponding diamino-functionalized copillar[5]arene,which were prepared by Gabriel reaction according to the reported method.Single-crystals of six copillar[5]arenes were determined by X-ray diffraction.An ORTEP of compounds showed that the two chains units of Schiff base exist in the outside of the cavity of pillar[5]arene.Furthermore,the complexing ability of these Schiff bases to transition metal ions were investigated by UV and fluorescence spectroscopy.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
Four chiral diorganotin complexes of N-[4-(diethylamino)salicylidene]-(L)-tryptophane,R2Sn[4-(Et2N)-2-OC6H3CH=NCH(CH2Ind)COO](Ind=3-indolyl;R=Me(1);Et,(2);n-Bu(3);Cy(cyclohexyl)(4)),have been synthesized and character...Four chiral diorganotin complexes of N-[4-(diethylamino)salicylidene]-(L)-tryptophane,R2Sn[4-(Et2N)-2-OC6H3CH=NCH(CH2Ind)COO](Ind=3-indolyl;R=Me(1);Et,(2);n-Bu(3);Cy(cyclohexyl)(4)),have been synthesized and characterized by elemental analysis,IR,and 1H and 13C NMR spectra.The crystal structures of 1-CH3OH-CHCl3,2,3-CH3OH and 4-CH3CH2OH have been determined by single-crystal X-ray diffraction.The complexes crystallize in orthorhombic system with P212121 space group,and the tin atoms are in distorted trigonal bipyramidal geometry and form five-and six-membered chelate rings with the chiral ONO tridentate ligand N-[4-(diethylamino)salicylidene]-(L)-tryptophane.In the complexes,the molecules are connected into one-dimensional supramolecular chain by intermolecular N–H…O–H…O=C or N–H…O–C hydrogen bonds.The fluorescence spectrum indicates that the complexes may be explored for potential blue luminescent materials.Bioassay results show that 3 and 4 belong to the efficient cytostatic agents against A549 human tumor cell.展开更多
The 2-acetyl-benzimidazoledehyde-gly- cine Schiff-base ligand and the corresponding Pr(III) complex Pr2L3(NO3)3·2CH3OH (L=C11H10N3O2) were synthesized in methanol and characterized by a series of methods, includi...The 2-acetyl-benzimidazoledehyde-gly- cine Schiff-base ligand and the corresponding Pr(III) complex Pr2L3(NO3)3·2CH3OH (L=C11H10N3O2) were synthesized in methanol and characterized by a series of methods, including chemical analysis, elemental analysis, TOF-MS, 1H NMR, UV-, IR-, Raman spectra, thermal analysis, and the three-dimension fluores- cence excitation and emission spectra. The Pr(III) complex exhibits extraordinary water-solubility and the Pr(III) hydroxide appears at pH≥13. The complex also possesses specific fluorescent properties. Thus, at the excitation wavelengths 200.0-280.0 and 260-350 nm the fluorescence bands were observed at 290.0 and 400.0 nm, respectively.展开更多
A bilateral Schiff base is reported for the colorimetric and fluorometric dual-channel sensing of Hg^(2+)ions by taking advantage of the hydrolysis of carbon-nitrogen double bond,altering an ICT state mechanism and th...A bilateral Schiff base is reported for the colorimetric and fluorometric dual-channel sensing of Hg^(2+)ions by taking advantage of the hydrolysis of carbon-nitrogen double bond,altering an ICT state mechanism and then Hg^(2+) ions coordinating with amino moieties of 1,5-DAN and leading to the aggregation of 1,5-DAN.Meanwhile,it formed a stable neutral complex of amino-Hg-amino.In addition,test strips based on L were fabricated,which also exhibited a good selectivity to Hg^(2+) as in solution.This work provides a novel approach for the selective recognition of mercury ions.Notably,the color changes are very significant and all the recognition processes can be observed by the naked eyes.We believe the test strips can act as a convenient and efficient Hg^(2+) test kit.展开更多
A new hydrazone Schiff base(N,N′-bis[1-(5-Br-2-methoxyphenol-6-yl)methylidene]benzil dihydrazone)(1)and its copper(II)complex Cu2(L)2·H2O·0.25CH3OH(2)have been synthesized and characterized by IR,elemental ...A new hydrazone Schiff base(N,N′-bis[1-(5-Br-2-methoxyphenol-6-yl)methylidene]benzil dihydrazone)(1)and its copper(II)complex Cu2(L)2·H2O·0.25CH3OH(2)have been synthesized and characterized by IR,elemental analysis,1H-NMR and single-crystal X-ray analysis.The crystal of the complex(2)belongs to triclinic,space group Pī with a=12.993(13),b=14.454(15),c=16.291(17),α=102.309(14)°,β=91.327(14)°,γ=95.526(15)°,V=2972(5)3,Dc=1.642 g/cm3,Z=2,Mr =1469.77,μ(Mo Kα)=3.467mm-1,F(000)=1464.The complex(2)forms a 1D chain-like structure constructed by noncovalent interaction of Cu…N and Cu…Br and π-π stacking interactions.The adjacent chains are further interconnected into a 3D supramolecular architecture by the interaction of Br…Br.The fluorescence of the title compounds(1)and(2)were also discussed.展开更多
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<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>
基金financially supported by the National Natural Science Foundation of China (Nos. 21172190, 21372192)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di(t-butyl) substituted derivatives with corresponding diamino-functionalized copillar[5]arene,which were prepared by Gabriel reaction according to the reported method.Single-crystals of six copillar[5]arenes were determined by X-ray diffraction.An ORTEP of compounds showed that the two chains units of Schiff base exist in the outside of the cavity of pillar[5]arene.Furthermore,the complexing ability of these Schiff bases to transition metal ions were investigated by UV and fluorescence spectroscopy.
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.
基金Financially supported by the Natural Science Foundation of Shandong Province(ZR2013BM007)the National Natural Science Foundation of China(21702119)
文摘Four chiral diorganotin complexes of N-[4-(diethylamino)salicylidene]-(L)-tryptophane,R2Sn[4-(Et2N)-2-OC6H3CH=NCH(CH2Ind)COO](Ind=3-indolyl;R=Me(1);Et,(2);n-Bu(3);Cy(cyclohexyl)(4)),have been synthesized and characterized by elemental analysis,IR,and 1H and 13C NMR spectra.The crystal structures of 1-CH3OH-CHCl3,2,3-CH3OH and 4-CH3CH2OH have been determined by single-crystal X-ray diffraction.The complexes crystallize in orthorhombic system with P212121 space group,and the tin atoms are in distorted trigonal bipyramidal geometry and form five-and six-membered chelate rings with the chiral ONO tridentate ligand N-[4-(diethylamino)salicylidene]-(L)-tryptophane.In the complexes,the molecules are connected into one-dimensional supramolecular chain by intermolecular N–H…O–H…O=C or N–H…O–C hydrogen bonds.The fluorescence spectrum indicates that the complexes may be explored for potential blue luminescent materials.Bioassay results show that 3 and 4 belong to the efficient cytostatic agents against A549 human tumor cell.
文摘The 2-acetyl-benzimidazoledehyde-gly- cine Schiff-base ligand and the corresponding Pr(III) complex Pr2L3(NO3)3·2CH3OH (L=C11H10N3O2) were synthesized in methanol and characterized by a series of methods, including chemical analysis, elemental analysis, TOF-MS, 1H NMR, UV-, IR-, Raman spectra, thermal analysis, and the three-dimension fluores- cence excitation and emission spectra. The Pr(III) complex exhibits extraordinary water-solubility and the Pr(III) hydroxide appears at pH≥13. The complex also possesses specific fluorescent properties. Thus, at the excitation wavelengths 200.0-280.0 and 260-350 nm the fluorescence bands were observed at 290.0 and 400.0 nm, respectively.
基金the National Natural Science Foundation of China(Nos.21064006,21262032 and 21161018)the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China(No.IRT1177)+1 种基金the Natural Science Foundation of Gansu Province(No.1010RJZA018)the Youth Foundation of Gansu Province(No.2011GS04735)and NWNU-LKQN-11-32.
文摘A bilateral Schiff base is reported for the colorimetric and fluorometric dual-channel sensing of Hg^(2+)ions by taking advantage of the hydrolysis of carbon-nitrogen double bond,altering an ICT state mechanism and then Hg^(2+) ions coordinating with amino moieties of 1,5-DAN and leading to the aggregation of 1,5-DAN.Meanwhile,it formed a stable neutral complex of amino-Hg-amino.In addition,test strips based on L were fabricated,which also exhibited a good selectivity to Hg^(2+) as in solution.This work provides a novel approach for the selective recognition of mercury ions.Notably,the color changes are very significant and all the recognition processes can be observed by the naked eyes.We believe the test strips can act as a convenient and efficient Hg^(2+) test kit.
文摘A new hydrazone Schiff base(N,N′-bis[1-(5-Br-2-methoxyphenol-6-yl)methylidene]benzil dihydrazone)(1)and its copper(II)complex Cu2(L)2·H2O·0.25CH3OH(2)have been synthesized and characterized by IR,elemental analysis,1H-NMR and single-crystal X-ray analysis.The crystal of the complex(2)belongs to triclinic,space group Pī with a=12.993(13),b=14.454(15),c=16.291(17),α=102.309(14)°,β=91.327(14)°,γ=95.526(15)°,V=2972(5)3,Dc=1.642 g/cm3,Z=2,Mr =1469.77,μ(Mo Kα)=3.467mm-1,F(000)=1464.The complex(2)forms a 1D chain-like structure constructed by noncovalent interaction of Cu…N and Cu…Br and π-π stacking interactions.The adjacent chains are further interconnected into a 3D supramolecular architecture by the interaction of Br…Br.The fluorescence of the title compounds(1)and(2)were also discussed.