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1.
The novel lanthanide(III) complexes [La(NO3)3(H2O)L] 1, and [Ln(NO3)3L] (Ln=Pr 2, Sm 3, Gd 4) where L=N,N-bis(pyridin-2-ylmethylene)benzene-1,2-diamine, have been obtained by direct reaction of the Schiff base ligand and the corresponding hydrated lanthanide(III) nitrates in methanol. All complexes were characterized spectroscopically and thermogravimetrically. Complex 3 was also characterized with crystallographic studies. In the molecular structure of 3, Sm(III) is surrounded by all four nitrogen atoms of the Schiff base and six oxygen atoms belonging to three bidentate chelating nitrato ligands.  相似文献   

2.
This paper discloses two new side-chain metallopolymers containing an unsymmetrical organometallic Schiff base complex of Ni(II) linked to a polymethylmethacrylate (PMMA) matrix. The neutral ferrocene substituted Schiff base complex 1, Ni{CpFe(η5-C5H4)-C(O)CH=C(CH3)N–o-C6H4N=CH-(2-O,5-OH-C6H3)} where (Cp = η5-C5H5), was synthesized via template reaction by condensation of the tridentate half-unit metalloligand Fc-C(O)CH=C(CH3)-N(H)-o-C6H4NH2 (Fc = ferrocenyl = CpFe(η5-C5H4)) with 2,5-dihydroxybenzaldehyde in the presence of nickel(II) acetate tetrahydrate. The binuclear Schiff base complex of Ni(II) containing an aromatic free hydroxyl group was reacted under basic conditions with PMMA to afford, upon trans-esterification reaction, metallopolymers 2 (complex 1 monomeric unit/PMMA = 1/5) and 3 (complex 1 monomeric unit/PMMA = 1/3). Elemental analysis, FT-IR, 1H and 13C NMR spectroscopies, and cyclic voltammetry were utilized to characterize the newly synthetized compounds. Surface morphology of the metallopolymer film of 2 was studied using atomic force microscopy.  相似文献   

3.
Three binuclear lanthanide complexes [Nd2(L1)3(MeOH)]·MeOH·H2O (1) and [Ln2(H2L2)2(OAc)4]·2(CF3SO3)·MeOH·EtOH (Ln = Nd (2) and Ho (3)) were prepared using two Schiff base ligands. Interestingly, 1 has a triple-decker structure with two lanthanide ions enclosed by three rigid conjugated Schiff base ligands (H2L1), while 2 and 3 show nanoscale ring structures (8 × 12 × 12 Å) formed by flexible long-chain Schiff base ligands (H2L2, ~ 23 Å) with the lanthanide ions located in the center. Upon excitation of the ligand-centered absorption bands, 12 and 3 show typical NIR emission spectra for Nd3 + and Ho3 + ions, respectively. In 1, the Nd(III) centers are shielded within the decker-like structure and surrounded by chromogenic Schiff base ligands (energy transfer donors). Luminescence studies show that the NIR emission lifetime of 1 is longer than that of 2 in solution.  相似文献   

4.
Four lanthanide coordination polymers, {[Ln(HPDA)(PDA)(H2O)2]·4H2O} n (Ln?=?Sm (1), Eu (2), Tb (3)) and {[Sm3(H2PDA)2(HPDA)2(PDA) (OH)5(H2O)3]·2dta·4H2O} n (4) (H2PDA?=?pyridine-2,6-dicarboxylic acid, dta?=?diethyl amine), have been synthesized under hydrothermal conditions and were characterized by elemental analysis, IR spectrometer, and single-crystal X-ray crystallography. In the complexes 13, the 1D chains are assembled into 2D layer by hydrogen bonds formed between the carboxyl groups, and were further assembled into 3D framework by hydrogen bonds and π–π stacking interactions. In complex 4, each Sm3+ ion connected to the neighboring Sm3+ ion through bridging carboxyl oxygen atoms, and then give rise to a new 2D layered open-framework structure. The 3D supramolecular structure of 4 is constructed through hydrogen-bonding and π–π stacking interactions between adjacent metal–organic polymeric coordination chains. Complexes 13 were dispersed in mesoporous materials SBA-15 in DMF solution (denoted as ML-SBA-15, ML?=?1, 2, 3), which were characterized by XRD, IR, and fluorescence spectra. Compared to the complexes 13, the photoluminescence efficiency of hybrid material was improved by the energy transition between mesoporous materials and the complexes. The complexes encapsulated in mesoporous materials SBA-15 exhibited stronger luminescence intensity and longer fluorescence lifetime.  相似文献   

5.
Four novel lanthanide(III) coordination polymers [Ln(L)1.5(H2O)2]·5H2O [Ln = Sm (1), Eu (2), Tb (3), Dy (4)] have been hydrothermally synthesized by the reaction of 1,2-bis[4-amino-5-carboxylmethylthio-(1,2,4-triazol-3-yl)]ethane (H2L) with lanthanide(III) salts, and structurally characterized by single crystal X-ray diffraction. Polymers 14 are isostructural, in which all the LnIII atoms are nine-coordinated and the carboxylate groups adopt three different coordination modes (bidentate chelate, bidentate bridging, bidentate chelate bridging) to connect LnIII atoms. These polymers exhibit 3D network structures with 2-fold interpenetration, in which intriguing 1D channels are observed. Besides, the spectra properties of the title polymers are investigated, the strong luminescence characteristics of 23 are found.  相似文献   

6.
A diketone-based tridentate Schiff base, 3-[(2-hydroxyphenyl)amino]-1,3-diphenylprop-2-en-1-one (H2L), and its oxo-vanadium(V) dimer complex, [VO(L)(OMe)]2, were synthesized and characterized using spectroscopic and physicochemical techniques. Single crystal X-ray diffraction indicated that the Schiff base ligand in its deprotonated form was found to bind to the V(V) ion through the azomethine nitrogen, amine and phenolic oxygens in a distorted octahedral geometry. The other positions around the V(V) center were occupied by an oxido group and two oxygens from methoxido ligands. Antimicrobial studies showed that the synthesized complex indicated significant antimicrobial activities against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 33591 and 29213) bacteria while no antibacterial activity was observed for the ligand alone. The potential of [VO(L)(OMe)]2 as an antimicrobial agent, was additionally investigated using molecular docking of the complex with GlcN-6-P synthase.  相似文献   

7.
A series of one-dimensional coordination polymers assembled from LnNO3 · 6H2O (Ln = Sm(1), Eu(2), Tb(3), La(4), Ce(5), Pr(6), Nd(7), Dy(8)), quinoline-2,3-dicarboxylic acid (2,3-H2qldc) and 1,10-phenanthroline (phen) formulated as [Ln(2,3-qldc)(3-qlc)(phen)]n (3-Hqlc = quinoline-3-carboxylic acid) were obtained under hydrothermal conditions. It is remarkable that in situ hydrothermal decarboxylation was observed during preparing these polymers. Complexes 18 were characterized by elemental analyses, IR spectroscopy and single crystal X-ray diffraction analyses. The thermal stabilities and photoluminescence properties of these complexes have been investigated.  相似文献   

8.
Six novel photoluminescent Ln–Cu(I) heterobimetallic 3D coordination polymers, [LnCu (pyip2 )2(H2O)]n (16) (where Ln is Pr, Nd, Sm, Eu, Gd, Ho, respectively, and H2pyip = 5-(4-pyridyl) isophthalic acid) have been synthesized in a concise and reproducible manner under hydrothermal conditions. All of these substances were fully characterized by appropriate spectroscopic methods and elemental analysis. Structural determinations revealed that 16 are isomorphic and display 3D frameworks. Luminescent properties of the obtained compounds have been studied in detail revealing light emissions of warm white, cool white and light blue for 3, 4 and 5, respectively. The effectiveness of association of a rare earth with a transition metal in producing valuable luminescent materials for practical applications is demonstrated.  相似文献   

9.
Reaction of LnCl3 first with three equivalent of C5H5Na in THF, then with one equivalent of benzyl mercaptan, led to complexes of [(C5H5)2Ln(SCH2Ph)]2 (Ln?=?Sm(1), Yb(2)), being characterized by infrared spectra, elemental analyses and X-ray crystallography for 2. Complex 2 is a dimer with two thiolate ligands as bridging groups in eight coordinate. The Yb-S(benzyl) bonds in 2 (2.703(19) and 2.719(2) Å, respectively) were longer than the Yb-S(aryl) bonds (about 2.640 Å) in analogous complexes. The catalytic property for the polymerization of ε-caprolactone by 1 and 2 was studied. Similar experiment was also made with [(C5H5)2Ln(SPh-p-CH3)(THF)]2 (Ln?=?Sm(3), Yb(4)) for comparison. It was found that complex 2 showed the activity best, and the activity decreased in the order of 2?>?3?>?1?>?4. When [ε-CL]0/[Ln] was 500 and the polymerization temperature was 35°C, complex 2 catalyzed the polymerization in living character, which could not be achieved by lanthanide arylthiolates such as 3 and 4.  相似文献   

10.
Two type lanthanide complexes obtained by salen-type ligand N,N’-ethylenebis(salicylideneimine) (H2La) and N,N’-ethylene-bis(3-methoxysalicylideneimine) (H2Lb) have been isolated. They are 2D coordination polymer [Yb(H2La)1.5(NO3)3] n (1), mononuclear Ln(H2Lb)(NO3)3 [Ln = Sm (2), Ho (3)]. The structures of 13 were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated.  相似文献   

11.
Hexanuclear 4d–4f heterometallic complexes, [Ln2Ag4(ina)8(H2O)10][NO3] 2 · 4H2O [Ln = Sm (1), Eu (2), Dy (3) and Hina = isonicotinic acid], have been synthesized by the hydrothermal reaction of lanthanide oxides, AgI, and isonicotinic acid at a suitable temperature. Single-crystal X-ray diffraction studies indicate that these 4d–4f complexes consist of extended 1D zigzag chains structure built upon [Sm2Ag4(ina)8(H2O)10] subunits connected by Ag–Ag interactions. Furthermore, the photoluminescent properties of the complex 2 were studied.  相似文献   

12.
N-Ferrocenoyl glycine ester derivatives FcCONHCH2COOR (Fc=(η5-C5H5)Fe(η5-C5H4); R=methyl (1), ethyl (2) and benzyl (3)) have been prepared by coupling ferrocene carboxylic acid to a series of glycine esters using 1,3-dicyclohexylcarbodiimide (DCC), 1-hydroxybenzotriazole (HOBT) and Et3N in CH2Cl2. The electrochemical anion sensing using a platinum microdisk working electrode of these N-ferrocenoyl glycine ester derivatives is reported. The crystal structure of 1 has been determined; principal dimensions are amide N(H)CO 1.229(3) Å, ester CO 1.183(3) Å with N–H⋯OC(amide) as the primary intermolecular hydrogen bond, N⋯O 2.804(3) Å.  相似文献   

13.
Three new two-dimensional 3d–4f isostructural heterometallic coordination polymers, namely [Ln2Zn(2,3-pydc)4(H2O)4·4H2O]n (Ln = Sm (1), Eu (2), Gd (3), 2,3-pydcH2 = pyridine-2,3-dicarboxylic acid) have been successfully synthesized by the hydrothermal reactions of Ln2O3, Zn(NO3)2·6H2O, H2pydc and H2O. X-ray diffraction analyses reveal that they possess a 2D heterometallic framework containing 1D lanthanide chains based on dimeric [Ln(2,3-pydc)2(H2O)2]2 unit. The Zn(II) ion, which is six-coordinated by four oxygen and two nitrogen atoms from four 2,3-pydc2− ligands, as a bridge, links the lanthanide chains to make the 1D chains further extend into 2D layer framework. Furthermore, the neighboring layers are assembled into three-dimensional supramolecular network through inter-layer O–HO and C–HO hydrogen-bond interactions. In addition, the solid-state luminescent property of complex 2 was investigated.  相似文献   

14.
Four rare earth organodisulfonate coordination polymers, {[Tb2(phen)4(nds)3(H2O)2]·4H2O}n (1), {[Ln(phen)(nds)(OH)]}n[Ln = Sm (2), Nd (3)], {[Tb(phen)2(nds)0.5(OH)·H2O]·(nds)0.5}n (4), were synthesized under the solvothermal conditions by using ligands 2,6-naphthalenedisulfonate (L = nds) and 1,10-phenanthroline (L′ = phen). Single-crystal X-ray diffraction reveals that compounds 1 and 4 exhibit different 1-D and 2-D crystal structures just owing to the single difference of stoichiometric ratio of the reactants in the synthesis process. Compounds 2 and 3 show 3-D structures with similar Ln coordination mode. Besides, the photoluminescent property in solid state of 1 was investigated in detail.  相似文献   

15.
A series of trivalent lanthanide complexes of type [Ln(L) NO3)(S)n](NO3)m(S)n, have been synthesized by the reaction of 2,6-diacetylpyridine-bis-(benzoylhydrazone) (H2L) with lanthanide(III) nitrates in ethanol. These complexes have been characterized by analysis, molar conductance, magnetic measurements, infrared spectral studies and X-ray diffraction. The analytical data revealed the formation of 1:1 (metal:ligand) stoichiometry. Molar conductance in dmf gives 2:1 electrolytes in all the complexes. Magnetic moment values are close proximity of the Van Vleck values. IR study suggests the coordination of the ligand through the azomethine and the oxygen of the hydrazonic moiety. The nitrate ion is also found to be bidentate in all the complexes. The crystal structures were determined. 6, C27H31N6O7S2Gd: a=b=8.6821(4) Å, c=84.363(5) Å, tetragonal P41212 and Z=8. bf 7, C25H25N6O6SDy: a=11.750(3) Å, b=13.250(3) Å, c=36.000(6) Å, β=98.50(2), monoclinic, C2/c, Z=8. 9, C24H25N6O7Yb: a=10.750(2) Å, b=17.750(3) Å, c=14.250(4) Å, β=99.00(2), monoclinic, P21/n, Z=4. In these complexes the lanthanide ion assumes a nine coordinated geometry for Gd and an eight coordinated geometry for Dy and Yb.  相似文献   

16.
Two chiral Schiff base-containing complexes, [Cu(L1)](ClO4)2·H2O (1, L1 = (S,S)-N1,N2-bis((1H-imidazol-4-yl)methylene)cyclohexane-1,2-diamine) and [Ni(L2)2](ClO4)2 (2, L2 = (S,S)-N1-((1H-imidazol-4-yl)methylene)cyclohexane-1,2-diamine) were synthesized from the reaction mixture of 1H-imidazole-4-carbaldehyde, (S,S)-1,2-diaminocyclohexane and Cu(ClO4)2·6H2O or Ni(ClO4)2·6H2O in methanol. Single-crystal X-ray diffraction analyses reveal that the in situ generated chiral Schiff base ligands L1 and L2 are bisubstituted and monosubstituted, respectively, corresponding to the different metal ions CuII and NiII. Variable-frequency and -temperature dielectric properties of 1 and 2 have been studied.  相似文献   

17.
New ligand [KH2B(tz*)2] (tz*=3,5-dimethyl-1,2,4-triazolyl) has been synthesized and the reactions of two different metal salts (copper and zinc) with the new ligand in agar gave two similar crystalline polymorphic forms: [Cu{H2B(tz*)2}2(H2O)] (1) and [Zn{H2B(tz*)2}2(H2O)] (2). A single crystal X-ray study revealed that the compound 1 was the monoclinic system with space group C2/c and a=8.462(3) Å, b=14.039(6) Å, c=19.991(8) Å, β=94.622(7)°, Z=4, R1=0.0451, wR2=0.1110. And the compound 2 was the monoclinic system with space group C2/c and a=8.4214(4) Å, b=13.8765(7) Å, c=20.2969(6) Å, β=95.615(2)°, Z=4, R1=0.0667, wR2=0.1375. The metal(II) ion in the complex is five-coordinated with four nitrogen atoms which come from triazolyl and one oxygen atom which come from water molecular. In both compounds, the hydrogen atoms of water molecule are connected by hydrogen bonding with N atoms of two adjacent complex molecules to form 2-D planes. The spectroscopic results are consistent with the crystallographic study.  相似文献   

18.
The copper(II) complex [Cu(salgly)(bpy)]·4H2O (1), where salgly is a tridentate glycinatosalicylaldimine Schiff base ligand, is prepared and structurally characterized. The complex is found to be catalytically active in the oxidation of ascorbic acid by dioxygen and the process is also effective in the presence of benzylamine giving benzaldehyde as a product, thus modeling the activity of the CuB site of dopamine β-hydroxylase.  相似文献   

19.
Two types of lanthanide thiolato-carboxylate complexes, [Type I: [Yb(dtba) (Hdtba)] n (1), Type II: [Ln(dtba)1.5(biim)] n (Ln = Pr (2a), Nd (2b), Sm (2c), Eu (2d), Gd (2e), Tb (2f), Dy (2g), H2dtba = 2,2′-dithiodibenzoic acid, bimm = diimidazole)] have been obtained by hydrothermal method and characterized by the single-crystal X-ray diffraction, IR, 2D-COS IR, TG and the luminescence analysis. The H2dtba ligand came from the in situ S–S function reaction of 2-mercaptobenzoic acid (H2mba) under the hydrothermal condition. Complex 1 is a 2D bamboo-like sqr-topology layered structure, and the 3D (4, 4, 6)-connected supramolecular frameworks is produced by the hydrogen bonds of O–H···O. Complexes of type II (from 2a to 2g) are isostructural and they are assigned to 1D rope-like chains by introducing the chelating ligand of diimidazole. These 1D rope-like chains are further linked by N–H···O hydrogen bonds into a 3D supramolecular framework with CdSO4-type topology. Photoluminescence studies reveal that complexes 2b, 2c, 2d, 2f, 2g exhibit strong lanthanide characteristic emission bands in the solid state at room temperature.  相似文献   

20.
A new cyclic binuclear Ni(II) complex, [Ni2(H2L)2] · 4MeOH (1), has been synthesized using the Schiff base N′1,N′3-bis(2-hydroxybenzylidene)malonohydrazide (H4L). The X-ray crystal structure of 1 shows that the ligand coordinates in the dianionic keto form (H2L2 ) via mutual sharing of two Ni(II) ions. Complex 1 acts as a heterogeneous catalyst for the Henry reaction in water. A maximum conversion of ca. 93% was obtained under optimized conditions.  相似文献   

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