Four ternary lanthanide complexes with unsaturated acid and 1,10-phenanthroline are prepared in methanol and characterized by elemental analysis, molar conductance, UV, IR, (()~1H) NMR and XPS. The results from this p...Four ternary lanthanide complexes with unsaturated acid and 1,10-phenanthroline are prepared in methanol and characterized by elemental analysis, molar conductance, UV, IR, (()~1H) NMR and XPS. The results from this paper show that the complexes Ln(phen)(SA)_3·2H_2O or Ln(phen)(CA)_3·H_2O (Ln=Ce(Ⅲ), Sm(Ⅲ) and Eu(Ⅲ), (phen=1,10-)phenanthroline, SA=Sorbate and CA=Cinnamate) has better anti-inflammatory effect than cerium nitrate and their gremores are steadier than cerium nitrate gremor. And there is a kind of medicament which can replace the cerium nitrate gremor completely in treating burn.展开更多
The two compounds of [Ln(2-FBA)3·2,2'-bpy ]2(2-FBA = 2-fluorobenzoato, 2,2'-bpy = 2,2'-bipyridine, Ln = Eu(1 ), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method....The two compounds of [Ln(2-FBA)3·2,2'-bpy ]2(2-FBA = 2-fluorobenzoato, 2,2'-bpy = 2,2'-bipyridine, Ln = Eu(1 ), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoelinie system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2'-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. ^5D0→^7Fj(j = 1 - 4) transition emission of Eu^3+ ion was observed.展开更多
Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1...Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L.展开更多
A series of novel rare earths complexes with Schiff base of pridoxylidence-glycine acid (HL) were synthesized in absolute methanol under argon atmosphere. The complexes were characterized by elemental analysis, molar ...A series of novel rare earths complexes with Schiff base of pridoxylidence-glycine acid (HL) were synthesized in absolute methanol under argon atmosphere. The complexes were characterized by elemental analysis, molar conductivity, IR, UV spectra, and H-NMR spectra et al. Data indicate that the complexes have a general formula Ln LCl2.3H(2)O (Ln = La, Y, Sm, Gd, Dy, Yb; L = C10H11N2O4). Effects of the complexes (Ln = La) on physiological and biochemical indexes of plants under Pb stress were studied. The experiments shown that the complexes obviously mitigated Pb pollution results in decreasing of chlorophyll content, rising of cell membrane permeability, changing catalase(CAT) and distribution of Pb.展开更多
By the reaction of Cp 3Ln with HL(Cp=η 5 C 5H 5, cyclopentadienyl; Ln=Yb, Tm, Er, Ho, Dy, Gd, Pr; HL=benzohydroximic acid), seven new complexes of the general formula Cp 2LnL were synthesized. All the complexes...By the reaction of Cp 3Ln with HL(Cp=η 5 C 5H 5, cyclopentadienyl; Ln=Yb, Tm, Er, Ho, Dy, Gd, Pr; HL=benzohydroximic acid), seven new complexes of the general formula Cp 2LnL were synthesized. All the complexes were characterized by elemental analysis, infrared spectra, and mass spectra. Based on these data, the probable structure was proposed.展开更多
A series of new complexes of formula Ln(acac)_s(Ph_3PO)_3 (where Ln^(3+)=Nd^(3+), Sm^(3+), Eu^(3+), Tb^(3+), Ho^(3+)) have been prepared and characterized. The coordination of two ligands with lanthanide ions are stud...A series of new complexes of formula Ln(acac)_s(Ph_3PO)_3 (where Ln^(3+)=Nd^(3+), Sm^(3+), Eu^(3+), Tb^(3+), Ho^(3+)) have been prepared and characterized. The coordination of two ligands with lanthanide ions are studied by IR spectra, ~1H, ^(13)C, ^(31)P-NMR and metal-ligand charge tranafer tranaition is also discussed via electronic adaorption and luminescence spectroscopy.展开更多
New tanthanide comptexes of acetylacetonate-meso-tetra- (4-pyridyt)porphyrin(LnTpypacac,Ln=Dy,Ho,Yb,Lu,H_2Tpyp= tetra-(4-pyridyl)-porphyrin,Hacac=acetylacetone)were prepared by reaction of Ln(acac)_3·3H_2O with H...New tanthanide comptexes of acetylacetonate-meso-tetra- (4-pyridyt)porphyrin(LnTpypacac,Ln=Dy,Ho,Yb,Lu,H_2Tpyp= tetra-(4-pyridyl)-porphyrin,Hacac=acetylacetone)were prepared by reaction of Ln(acac)_3·3H_2O with H_2Tpyp and were characterized by elemental analyses,ultra-viotet spectra,infrared spectra and thermal analyses.展开更多
The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of...The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of macromolecular lanthanide complexes has been published in literature.We have been successful in preparing lanthanide complexes with styrene-acrylic acid copolymer,someof which exhibite high activitiest in butadiene polymerization.It was found that the complexes showedthe double-double effect as they were characterized.In the present paper,the SAAC·Ln IR spectra whichcharacterize the double-double effect have been discussed in detail.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
Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) i...Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) ions; (2) organic ligand was then loaded into the channels of the Eu3+-exchanged zeolite by gas diffusion procedure. Loading of ligand into the channels of zeolite L was confirmed by element analysis. Luminescence spectroscopy has confirmed that lanthanide complex are formed in the nanochannels of zeolite L crystals. In addition to the sharp emissions of lanthanide ions, broad band ranged from 350~500 nm can also be observed. This study provides alternative method for fabricating full-color display materials.展开更多
(C5H5)3Ln(THF)reacted with amine bis(phenol) LH2 [ L = Me2NCH2CH2N {CH2-(2-O-C6H2-But^1-3-Me- 5)}2 ] in a 1:1 molar ratio in THF to generate the amine bis(phenolato) cyclopentadienyl lanthanide complexes LL...(C5H5)3Ln(THF)reacted with amine bis(phenol) LH2 [ L = Me2NCH2CH2N {CH2-(2-O-C6H2-But^1-3-Me- 5)}2 ] in a 1:1 molar ratio in THF to generate the amine bis(phenolato) cyclopentadienyl lanthanide complexes LLn(C5H5) (THF)·(THF),(Ln = La (1), n =0; Ln = Sm(2), n = 1) in high yields. Complexes 1 and 2 were fully characterized by elemental analysis, NMR (for 1) and IR spectra, and X-ray structural determination. The crystal data of complex 1 are monoclinic, P21/c space goup, a= 1.1595(1) nm, b = 1.8588(2) nm, c = 1.6647(1) nm, β = 98.490(2)°, V =3.5486(5) nm^3, Z =4, Dc = 1.338 mg· m^3,μ = 1240 mm^-1, F(000)= 1488, R =0.0249, wR = 0.0568. The crystal data of complex 2 are monoclinic, P21/c sp ace goup, a = 0.9692 (1) nm, b = 1.4583 (2) nm, c = 2.8192 (3) nm, = 96.805 (2)°, V = 3.9584 (7) nm^3, Z=4, Dc =1.340 mg · ma, μ = 1.524 mm^-1, F(000)= 1668, R =0.0346, wR =0.0756. The attempts failed to synthesize the amine bis(phenolate) lanthanide alkoxides by the reactions of complexes 1 and 2 with alcohols. The preliminary results revealed that complex 1 can initiate ε-caprolactone polymerization.展开更多
The characteristics of styrene-acrylic acid copolymer supported lanthanide complexes (SAAC Ln) (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tin, Yb, and Lu) were described. A comparison of the activities of SAAC...The characteristics of styrene-acrylic acid copolymer supported lanthanide complexes (SAAC Ln) (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tin, Yb, and Lu) were described. A comparison of the activities of SAAC·Ln was made. It was found that in the polymerization of butadiene, a peak in activity appeared at Nd and Pr, Sin, Eu and the heavy lanthanides exhibited low or no activities. The effects of some factors on the activities were discussed. The microstructure of the polymers obtained with all the lanthanides in the series were the same and the content of cis-1, 4 polybutadiene attained was more than 98%.展开更多
Two 3D Ln-organic coordination frameworks(Ln = Pr3+ for 1 and Er3+ for 2) have been constructed. Single-crystal X-ray diffraction analysis reveals that the two complexes have similar structures and belong to the m...Two 3D Ln-organic coordination frameworks(Ln = Pr3+ for 1 and Er3+ for 2) have been constructed. Single-crystal X-ray diffraction analysis reveals that the two complexes have similar structures and belong to the monoclinic C2/c space group. The trans-μ4-(η2:η1)-(η1:η1) 1,2-pda2- anions link the LnIII centers to generate a 2D network containing helical motif. The dimensionality is extended into a 3D architecture through cis-bis(μ2-η2:η1) 1,2-pda2- anions linking. The geometry of Ln3+ ions is single-capped anti-square prism. Two complexes were characterized by IR spectra and thermogravimetric analysis. The solid fluorescence of 1 and 2 was also investigated at room temperature.展开更多
Circularly polarized luminescence(CPL)is the emission featured spatial orientation equivalent to circular dichroism.Owning to the unique magnetic dipole-allowed but electric-dipole-forbidden 4f→4f transitions,chiral ...Circularly polarized luminescence(CPL)is the emission featured spatial orientation equivalent to circular dichroism.Owning to the unique magnetic dipole-allowed but electric-dipole-forbidden 4f→4f transitions,chiral lanthanide complexes have been recognized as ideal candidates to achieve unprecedented luminescence dissymmetry factor(glum).Their inherent electric-dipole-forbidden transition can be partly allowed,through the rational design of coordination ligands to lower the surrounding symmetry,further endowing them with relatively high quantum yields(QYs).Moreover,the blossom of supramolecular chemistry in lanthanide complexes allows for the construction of discrete oligomers and hierarchical assemblies,rendering them with enhanced chiroptical activities.Here,we deploy this review by summarizing recent advances in the chiroptical properties of lanthanide complexes,spanning multiple scales from isolated mononuclear individuals,discrete polynuclear oligomers,to infinite hierarchical assemblies.We first introduce the basic concept and several important parameters for the assessment of CPL activity.Then,isolated mononuclear lanthanide complexes coordinated with different types of antennas,along with the unique chirality transfer and induction in achiral lanthanide complexes were discussed.Next,the systematical discussion on chiroptical properties in discrete polynuclear lanthanide oligomers and infinite hierarchical lanthanide assemblies was presented.Meanwhile,the state-of-the-art applications of CPL-active lanthanide complexes were revisited.We end up this review with the conclusion and prospects,involving the rational design of ligands,directed and hierarchically precise self-assembly,and extending applications of chiral lanthanide complexes.展开更多
The complexes of rare earth elements with 1,2-diphenyl-4-butyl-3,5-Pyrazolidinedione (PBH, phenylbutazone) were synthesized and characterized by elemental analysis, molar conductance, IR, UV-Vis, EPR and magnetic mo...The complexes of rare earth elements with 1,2-diphenyl-4-butyl-3,5-Pyrazolidinedione (PBH, phenylbutazone) were synthesized and characterized by elemental analysis, molar conductance, IR, UV-Vis, EPR and magnetic moment measurements. Based on these studies the complexes were formulated as [Ln(PB)3(H2O)2].nH2O, where Ln=Eu(III), Gd(III), Tb(III), Dy(III) and Er(III). From IR spectra, it was found that PBH acted as a bidentate mono-ionic ligand coordinating through two carbonyl oxygen of the pyrazolidinedione ring. The thermal analysis of all the complexes was carried out at a heating rate of 10 oC/min. The kinetic aspects of the complexes were evaluated. The nega-tive entropy value of the complexes indicated a more ordered state for the activated complexes. The photoluminescence property of Tb(III) complex was investigated. It showed all the characteristic emission peaks of Tb^3+ with a life time of 0.98914 ms.展开更多
Lanthanide complexes of Eu(III), Gd(III), Nd(III), Sm(III), and Tb(III) with phenylthioacetic acid were synthesized and characterized by elemental analysis, mass, infrared radiation (IR), electronic spectr...Lanthanide complexes of Eu(III), Gd(III), Nd(III), Sm(III), and Tb(III) with phenylthioacetic acid were synthesized and characterized by elemental analysis, mass, infrared radiation (IR), electronic spectra, molar conductance, thermogravimetric analysis (TGA), and powder X-ray diffraction (XRD). The results showed that the lanthanide complexes were homodinuclear in nature. The two lanthanide ions were bridged by eight oxygen atoms from four carboxylate groups. Thermal decomposition profiles were consis- tent with the proposed formulations. Powder XRD studies showed that all the complexes were amorphous in nature. Antimicrobial studies indicated that these complexes exhibited more activity than the ligand itself. The DNA cleavage activity of the ligand and its complexes were assayed on CT DNA using gel electrophoresis in the presence of H202. The result showed that the Eu(Ⅲ) and Nd(Ⅲ) complexes completely cleaved the DNA. The anticancer activities of the complexes were also studied towards human cervical cancer cell line (HeLa) and colon cancer cells (HCT116) and it was found that the Eu(Ⅲ) and Nd(Ⅲ) complexes were more active than the corresponding Gd(Ⅲ), Sm(Ⅲ), Tb(Ⅲ) complexes and the free ligand on both the cancer cells.展开更多
Five lanthanide complexes of Ln2(dpdc)2(tpy)2(NO3)2(H2O)2 [Ln=La (1), Ce (2), Pr (3), Sm (4), Gd (5), H2dpdc=2,2’-biphenyldicarboxylic acid and tpy=2,2’:6’,2’’-terpyridine] were prepared at roo...Five lanthanide complexes of Ln2(dpdc)2(tpy)2(NO3)2(H2O)2 [Ln=La (1), Ce (2), Pr (3), Sm (4), Gd (5), H2dpdc=2,2’-biphenyldicarboxylic acid and tpy=2,2’:6’,2’’-terpyridine] were prepared at room temperature and characterized by X-ray diffraction, FT-IR and thermo-gravimetric analysis. The results showed that complexes 1–5 were isostructural and consisted of dinuclear units [Ln2(dpdc)2(tpy)2(NO3)(H2O)2] bridged by two dpdc2? ligands. The dinuclear units with strong intramolecular hydrogen bonds were assembled into 2D supramolecular layers by the weak π???π staking interactions between pyridine rings of tpy. The TG analysis showed that the complexes 1–5 behaved higher thermal stability with no mass loss at 〈 320 °C. The lanthanide contraction effect and the solid state luminescence properties of complexes 1–5 were also investigated. The luminescence emission spectra of complexes 1–5 exhibited ligands emission bands and complex 3 and 4 had no typical emission in the visible region.展开更多
Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)3(5,5’-dmebipy)(H2O)]2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5’-dmebipy=5,5’-dmethylbipyridine) were synthe...Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)3(5,5’-dmebipy)(H2O)]2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5’-dmebipy=5,5’-dmethylbipyridine) were synthesized and characterized by elemental analysis, infrared spectroscopy and single crystal X-ray diffraction. Findings indicated that complex 3 was a dinuclear molecule, and the center Dy3+ was eight-coordinated. Each dinuclear units could be connected by H bond and halogen-halogen interactions. Luminescent property of complex 2 suggested the typical intense emissions of Eu3+ ions. Thermal analysis showed that the complexes decomposed in three steps: the coordination water was lost firstly then the neutral ligand 5,5’dmebipy was lost and lastly the 2,3-DClBA ligand was lost.展开更多
A series-of lanthanide complexes including (Ind)(3)Sm(THF) (1), [(MeCP)(2)Sm(mu-SPh)(THF)](2),(2), [(MeCp)(2)Y(mu-O-i-Pr)](2) (3), (MeCp)(3)Sm.THF (4), Sm(SPh)(3) (hmpa)(3) (5), [(MeCp)(2)Y(mu-OCH2CF3)](2) (6) and (CF...A series-of lanthanide complexes including (Ind)(3)Sm(THF) (1), [(MeCP)(2)Sm(mu-SPh)(THF)](2),(2), [(MeCp)(2)Y(mu-O-i-Pr)](2) (3), (MeCp)(3)Sm.THF (4), Sm(SPh)(3) (hmpa)(3) (5), [(MeCp)(2)Y(mu-OCH2CF3)](2) (6) and (CF3CH2O)(3)Y(THF)(3) (7) were synthesized and they have good activity for the oligomerization of phenyl isocyanate. Among-them 5 shows,the highest activity. The conversion is as high as 96.2%, with 1/2500 of the molar ratio of cat. / PhNCO. The main components in oligomer were characterized to be a cyclodimer and a cyclotrimer. The ratio of cyclodimer,to cyclotrimer depends on the lanthanide complexes:used. 7 gave 85.2% cyclotrimer with 1/300 of the molar ratio of cat./PhNCO at 40 V for 0.5 h, while 5 gave 77.6% cyclodimer with 1/300 of the molar ratio of cat. /PhNCO at 40 degreesC for 4 h.展开更多
文摘Four ternary lanthanide complexes with unsaturated acid and 1,10-phenanthroline are prepared in methanol and characterized by elemental analysis, molar conductance, UV, IR, (()~1H) NMR and XPS. The results from this paper show that the complexes Ln(phen)(SA)_3·2H_2O or Ln(phen)(CA)_3·H_2O (Ln=Ce(Ⅲ), Sm(Ⅲ) and Eu(Ⅲ), (phen=1,10-)phenanthroline, SA=Sorbate and CA=Cinnamate) has better anti-inflammatory effect than cerium nitrate and their gremores are steadier than cerium nitrate gremor. And there is a kind of medicament which can replace the cerium nitrate gremor completely in treating burn.
文摘The two compounds of [Ln(2-FBA)3·2,2'-bpy ]2(2-FBA = 2-fluorobenzoato, 2,2'-bpy = 2,2'-bipyridine, Ln = Eu(1 ), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoelinie system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2'-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. ^5D0→^7Fj(j = 1 - 4) transition emission of Eu^3+ ion was observed.
文摘Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L.
文摘A series of novel rare earths complexes with Schiff base of pridoxylidence-glycine acid (HL) were synthesized in absolute methanol under argon atmosphere. The complexes were characterized by elemental analysis, molar conductivity, IR, UV spectra, and H-NMR spectra et al. Data indicate that the complexes have a general formula Ln LCl2.3H(2)O (Ln = La, Y, Sm, Gd, Dy, Yb; L = C10H11N2O4). Effects of the complexes (Ln = La) on physiological and biochemical indexes of plants under Pb stress were studied. The experiments shown that the complexes obviously mitigated Pb pollution results in decreasing of chlorophyll content, rising of cell membrane permeability, changing catalase(CAT) and distribution of Pb.
文摘By the reaction of Cp 3Ln with HL(Cp=η 5 C 5H 5, cyclopentadienyl; Ln=Yb, Tm, Er, Ho, Dy, Gd, Pr; HL=benzohydroximic acid), seven new complexes of the general formula Cp 2LnL were synthesized. All the complexes were characterized by elemental analysis, infrared spectra, and mass spectra. Based on these data, the probable structure was proposed.
文摘A series of new complexes of formula Ln(acac)_s(Ph_3PO)_3 (where Ln^(3+)=Nd^(3+), Sm^(3+), Eu^(3+), Tb^(3+), Ho^(3+)) have been prepared and characterized. The coordination of two ligands with lanthanide ions are studied by IR spectra, ~1H, ^(13)C, ^(31)P-NMR and metal-ligand charge tranafer tranaition is also discussed via electronic adaorption and luminescence spectroscopy.
文摘New tanthanide comptexes of acetylacetonate-meso-tetra- (4-pyridyt)porphyrin(LnTpypacac,Ln=Dy,Ho,Yb,Lu,H_2Tpyp= tetra-(4-pyridyl)-porphyrin,Hacac=acetylacetone)were prepared by reaction of Ln(acac)_3·3H_2O with H_2Tpyp and were characterized by elemental analyses,ultra-viotet spectra,infrared spectra and thermal analyses.
基金The project supported by the National Natural Science Foundation of China
文摘The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of macromolecular lanthanide complexes has been published in literature.We have been successful in preparing lanthanide complexes with styrene-acrylic acid copolymer,someof which exhibite high activitiest in butadiene polymerization.It was found that the complexes showedthe double-double effect as they were characterized.In the present paper,the SAAC·Ln IR spectra whichcharacterize the double-double effect have been discussed in detail.
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.
文摘Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) ions; (2) organic ligand was then loaded into the channels of the Eu3+-exchanged zeolite by gas diffusion procedure. Loading of ligand into the channels of zeolite L was confirmed by element analysis. Luminescence spectroscopy has confirmed that lanthanide complex are formed in the nanochannels of zeolite L crystals. In addition to the sharp emissions of lanthanide ions, broad band ranged from 350~500 nm can also be observed. This study provides alternative method for fabricating full-color display materials.
基金Project supported by the National Natural Science Foundation of China (20472063)the Key Laboratory of Organic Synthesis of Jiangsu Province
文摘(C5H5)3Ln(THF)reacted with amine bis(phenol) LH2 [ L = Me2NCH2CH2N {CH2-(2-O-C6H2-But^1-3-Me- 5)}2 ] in a 1:1 molar ratio in THF to generate the amine bis(phenolato) cyclopentadienyl lanthanide complexes LLn(C5H5) (THF)·(THF),(Ln = La (1), n =0; Ln = Sm(2), n = 1) in high yields. Complexes 1 and 2 were fully characterized by elemental analysis, NMR (for 1) and IR spectra, and X-ray structural determination. The crystal data of complex 1 are monoclinic, P21/c space goup, a= 1.1595(1) nm, b = 1.8588(2) nm, c = 1.6647(1) nm, β = 98.490(2)°, V =3.5486(5) nm^3, Z =4, Dc = 1.338 mg· m^3,μ = 1240 mm^-1, F(000)= 1488, R =0.0249, wR = 0.0568. The crystal data of complex 2 are monoclinic, P21/c sp ace goup, a = 0.9692 (1) nm, b = 1.4583 (2) nm, c = 2.8192 (3) nm, = 96.805 (2)°, V = 3.9584 (7) nm^3, Z=4, Dc =1.340 mg · ma, μ = 1.524 mm^-1, F(000)= 1668, R =0.0346, wR =0.0756. The attempts failed to synthesize the amine bis(phenolate) lanthanide alkoxides by the reactions of complexes 1 and 2 with alcohols. The preliminary results revealed that complex 1 can initiate ε-caprolactone polymerization.
文摘The characteristics of styrene-acrylic acid copolymer supported lanthanide complexes (SAAC Ln) (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tin, Yb, and Lu) were described. A comparison of the activities of SAAC·Ln was made. It was found that in the polymerization of butadiene, a peak in activity appeared at Nd and Pr, Sin, Eu and the heavy lanthanides exhibited low or no activities. The effects of some factors on the activities were discussed. The microstructure of the polymers obtained with all the lanthanides in the series were the same and the content of cis-1, 4 polybutadiene attained was more than 98%.
基金supported by the National Natural Science Foundation of China(21373178)the provincial college students’ innovation and entrepreneurship training program(1238)the Natural Science Foundation of Yanan university(YDZ2013-09)
文摘Two 3D Ln-organic coordination frameworks(Ln = Pr3+ for 1 and Er3+ for 2) have been constructed. Single-crystal X-ray diffraction analysis reveals that the two complexes have similar structures and belong to the monoclinic C2/c space group. The trans-μ4-(η2:η1)-(η1:η1) 1,2-pda2- anions link the LnIII centers to generate a 2D network containing helical motif. The dimensionality is extended into a 3D architecture through cis-bis(μ2-η2:η1) 1,2-pda2- anions linking. The geometry of Ln3+ ions is single-capped anti-square prism. Two complexes were characterized by IR spectra and thermogravimetric analysis. The solid fluorescence of 1 and 2 was also investigated at room temperature.
基金The authors sincerely acknowledge the financial support from the National Natural Science Foundation of China(12174151,61935009,11974142,and U21A2068)the Science and Technology Development Program of Jilin Province(20200401059GX).
文摘Circularly polarized luminescence(CPL)is the emission featured spatial orientation equivalent to circular dichroism.Owning to the unique magnetic dipole-allowed but electric-dipole-forbidden 4f→4f transitions,chiral lanthanide complexes have been recognized as ideal candidates to achieve unprecedented luminescence dissymmetry factor(glum).Their inherent electric-dipole-forbidden transition can be partly allowed,through the rational design of coordination ligands to lower the surrounding symmetry,further endowing them with relatively high quantum yields(QYs).Moreover,the blossom of supramolecular chemistry in lanthanide complexes allows for the construction of discrete oligomers and hierarchical assemblies,rendering them with enhanced chiroptical activities.Here,we deploy this review by summarizing recent advances in the chiroptical properties of lanthanide complexes,spanning multiple scales from isolated mononuclear individuals,discrete polynuclear oligomers,to infinite hierarchical assemblies.We first introduce the basic concept and several important parameters for the assessment of CPL activity.Then,isolated mononuclear lanthanide complexes coordinated with different types of antennas,along with the unique chirality transfer and induction in achiral lanthanide complexes were discussed.Next,the systematical discussion on chiroptical properties in discrete polynuclear lanthanide oligomers and infinite hierarchical lanthanide assemblies was presented.Meanwhile,the state-of-the-art applications of CPL-active lanthanide complexes were revisited.We end up this review with the conclusion and prospects,involving the rational design of ligands,directed and hierarchically precise self-assembly,and extending applications of chiral lanthanide complexes.
基金support from the University of Kerala for the award of afellowship
文摘The complexes of rare earth elements with 1,2-diphenyl-4-butyl-3,5-Pyrazolidinedione (PBH, phenylbutazone) were synthesized and characterized by elemental analysis, molar conductance, IR, UV-Vis, EPR and magnetic moment measurements. Based on these studies the complexes were formulated as [Ln(PB)3(H2O)2].nH2O, where Ln=Eu(III), Gd(III), Tb(III), Dy(III) and Er(III). From IR spectra, it was found that PBH acted as a bidentate mono-ionic ligand coordinating through two carbonyl oxygen of the pyrazolidinedione ring. The thermal analysis of all the complexes was carried out at a heating rate of 10 oC/min. The kinetic aspects of the complexes were evaluated. The nega-tive entropy value of the complexes indicated a more ordered state for the activated complexes. The photoluminescence property of Tb(III) complex was investigated. It showed all the characteristic emission peaks of Tb^3+ with a life time of 0.98914 ms.
文摘Lanthanide complexes of Eu(III), Gd(III), Nd(III), Sm(III), and Tb(III) with phenylthioacetic acid were synthesized and characterized by elemental analysis, mass, infrared radiation (IR), electronic spectra, molar conductance, thermogravimetric analysis (TGA), and powder X-ray diffraction (XRD). The results showed that the lanthanide complexes were homodinuclear in nature. The two lanthanide ions were bridged by eight oxygen atoms from four carboxylate groups. Thermal decomposition profiles were consis- tent with the proposed formulations. Powder XRD studies showed that all the complexes were amorphous in nature. Antimicrobial studies indicated that these complexes exhibited more activity than the ligand itself. The DNA cleavage activity of the ligand and its complexes were assayed on CT DNA using gel electrophoresis in the presence of H202. The result showed that the Eu(Ⅲ) and Nd(Ⅲ) complexes completely cleaved the DNA. The anticancer activities of the complexes were also studied towards human cervical cancer cell line (HeLa) and colon cancer cells (HCT116) and it was found that the Eu(Ⅲ) and Nd(Ⅲ) complexes were more active than the corresponding Gd(Ⅲ), Sm(Ⅲ), Tb(Ⅲ) complexes and the free ligand on both the cancer cells.
基金Project supported by National Basic Research Program of China(2010CB732300)Foundation of Zhejiang Province Education Commission of China(Y201224213)
文摘Five lanthanide complexes of Ln2(dpdc)2(tpy)2(NO3)2(H2O)2 [Ln=La (1), Ce (2), Pr (3), Sm (4), Gd (5), H2dpdc=2,2’-biphenyldicarboxylic acid and tpy=2,2’:6’,2’’-terpyridine] were prepared at room temperature and characterized by X-ray diffraction, FT-IR and thermo-gravimetric analysis. The results showed that complexes 1–5 were isostructural and consisted of dinuclear units [Ln2(dpdc)2(tpy)2(NO3)(H2O)2] bridged by two dpdc2? ligands. The dinuclear units with strong intramolecular hydrogen bonds were assembled into 2D supramolecular layers by the weak π???π staking interactions between pyridine rings of tpy. The TG analysis showed that the complexes 1–5 behaved higher thermal stability with no mass loss at 〈 320 °C. The lanthanide contraction effect and the solid state luminescence properties of complexes 1–5 were also investigated. The luminescence emission spectra of complexes 1–5 exhibited ligands emission bands and complex 3 and 4 had no typical emission in the visible region.
基金supported by the National Natural Science Foundation of China(21073053,21473049)the Natural Science Foundation of Hebei Province,China(B2016205207)
文摘Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)3(5,5’-dmebipy)(H2O)]2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5’-dmebipy=5,5’-dmethylbipyridine) were synthesized and characterized by elemental analysis, infrared spectroscopy and single crystal X-ray diffraction. Findings indicated that complex 3 was a dinuclear molecule, and the center Dy3+ was eight-coordinated. Each dinuclear units could be connected by H bond and halogen-halogen interactions. Luminescent property of complex 2 suggested the typical intense emissions of Eu3+ ions. Thermal analysis showed that the complexes decomposed in three steps: the coordination water was lost firstly then the neutral ligand 5,5’dmebipy was lost and lastly the 2,3-DClBA ligand was lost.
文摘A series-of lanthanide complexes including (Ind)(3)Sm(THF) (1), [(MeCP)(2)Sm(mu-SPh)(THF)](2),(2), [(MeCp)(2)Y(mu-O-i-Pr)](2) (3), (MeCp)(3)Sm.THF (4), Sm(SPh)(3) (hmpa)(3) (5), [(MeCp)(2)Y(mu-OCH2CF3)](2) (6) and (CF3CH2O)(3)Y(THF)(3) (7) were synthesized and they have good activity for the oligomerization of phenyl isocyanate. Among-them 5 shows,the highest activity. The conversion is as high as 96.2%, with 1/2500 of the molar ratio of cat. / PhNCO. The main components in oligomer were characterized to be a cyclodimer and a cyclotrimer. The ratio of cyclodimer,to cyclotrimer depends on the lanthanide complexes:used. 7 gave 85.2% cyclotrimer with 1/300 of the molar ratio of cat./PhNCO at 40 V for 0.5 h, while 5 gave 77.6% cyclodimer with 1/300 of the molar ratio of cat. /PhNCO at 40 degreesC for 4 h.