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1.
R. G. Bulgakov S. P. Kuleshov Z. S. Kinzyabaeva A. A. Fagin I. R. Masalimov M. N. Bochkarev 《Russian Chemical Bulletin》2007,56(10):1956-1959
Chemiluminescence (CL) upon the reaction of crystalline LnI2 (Ln = Dy, Nd) with water was found. The CL emitters are the Ln3+* electron-excited ions (Dy3+*, λmax = 470, 570 nm; Nd3+*, λ = 700–1200 nm) generated by the electron transfer from the LnII ions to the H2O molecules. The identified reaction products are H2, dissolved LnI3, and insoluble LnI(OH)2 (49–51% and 48–50% yield for DyI2 and NdI2, respectively). The treatment of NdI2 with an H2O solution in THF gives the NdI2OH(thf)2·3H2O complex and hydrogen.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1890–1893, October, 2007. 相似文献
2.
Single‐Molecule‐Magnet Behavior in the Family of [Ln(OETAP)2] Double‐Decker Complexes (Ln=Lanthanide,OETAP=Octa(ethyl)tetraazaporphyrin)
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Nelson Giménez‐Agulló Dr. Cristina Sáenz de Pipaón Louis Adriaenssens Dr. Marta Filibian Marta Martínez‐Belmonte Eduardo C. Escudero‐Adán Prof. Pietro Carretta Prof. Pablo Ballester Prof. José Ramón Galán‐Mascarós 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(40):12817-12825
Double‐decker complexes of lanthanide cations can be readily prepared with tetraazaporphyrins (porphyrazines). We have synthesized and characterized a series of neutral double‐decker complexes [Ln(OETAP)2] (Ln=Tb3+, Dy3+, Gd3+, Y3+; OETAP=octa(ethyl)tetraazaporphyrin). Some of these complexes show analogous magnetic features to their phthalocyanine (Pc) counterparts. The Tb3+ and Dy3+ derivatives exhibit single‐molecule magnet (SMM) behavior with high blocking temperatures over 50 and 10 K, respectively. These results confirm that, in double‐decker complexes that involve Tb or Dy, the (N4)2 square antiprism coordination mode has an important role in inducing very large activation energies for magnetization reversal. In contrast with their Pc counterparts, the use of tetraazaporphyrin ligands endows the presented [Ln(OETAP)2] complexes with extraordinary chemical versatility. The double‐decker complexes that exhibit SMM behavior are highly soluble in common organic solvents, and easily processable even through sublimation. 相似文献
3.
The biphenol based discrete ion-pair rare earth complexes,[Ln(EDBP)2(DME)Na(DME)3][Ln=Er(1),Yb(2), Sm(3)],were prepared and used as catalysts for the ring-opening polymerization(ROP)of 2,2-dimethyltrimethylene carbonate(DTC).Three complexes show moderate activities for the polymerization,and the catalytic activities increase in the following sequence:(Yb2 elimination was prepared. 相似文献
4.
Bipyrimidines have been chosen as (N∧N)(N∧N) bridging ligands for connecting metal centers. IrIII-LnIII (Ln = Nd, Yb, Er) bimetallic complexes [Ir(dfppy)2(μ-bpm)Ln(TTA)3]Cl were synthesized by using Ir(dfppy)2(bpm)Cl as the ligand coordinating to lanthanide complexes Ln(TTA)3·2H2O. The stability constants between Ir(dfppy)2(bpm)Cl and lanthanide ions were measured by fluorescence titration. The obvious quenching of visible emission from IrIII complex in the IrIII-LnIII (Ln = Nd, Yb, Er) bimetallic complexes indicates that energy transfer occurred from IrIII center to lanthanides. NIR emissions from NdIII, YbIII, and ErIII were obtained under the excitation of visible light by selective excitation of the IrIII-based chromophore. It was proven that Ir(dfppy)2(bpm)Cl as the ligand could effectively sensitize NIR emission from NdIII, YbIII, and ErIII. 相似文献
5.
[Cp2Ln(μ-SR)]2 was reacted with Ph2C=C=O to yield ketene mono-insertion products [Cp2Ln(μ-η1:η2-OC(SR)=CPh2)]2 [R=Bn, Ln=Yb (1), Er (2), Y (3) and R--Ph, Ln=Yb (4)], indicating that the reactions of organolanthanide thiolates with ketenes are independent of the nature of the thiolate ligand and the ketene as well as the reaction condition. These reactions could provide an efficient method for the synthesis of organolanthanide complexes with the a-thiolate-substituted enolate ligand. All these complexes were characterized by elemental analysis and spectroscopic properties and the structure of complex 1 was determined through X-ray single crystal diffraction analysis. 相似文献
6.
A. V. Ruseikina L. A. Solov’ev E. O. Galenko M. V. Grigor’ev 《Russian Journal of Inorganic Chemistry》2018,63(9):1225-1231
According to powder X-ray diffraction data, the crystal structures of compounds SrLnCuS3 (Ln = Er, Yb) have been refined by minimizing the derivative difference in the anisotropic approximation for all atoms. Crystals are orthorhombic, space group Cmcm, structure type KZrCuS3: a = 3.93128(3) Å, b = 12.9709(1) Å, c = 10.1161(1) Å, V = 515.843(9) Å3, ρcalc = 5.337 g/cm3, Z = 4, RDDM = 3.73%, RF = 2.06% (SrErCuS3); a = 3.91448(4) Å, b = 12.9554(1) Å, c = 10.0332(1) Å, V = 508.842(8) Å3, ρcalc = 5.487 g/cm3, Z = 4, RDDM = 3.56%, RF = 1.48% (SrYbCuS3). The structure of SrLnCuS3 is described by [LnCuS3] twodimensional layers formed by distorted CuS4 tetrahedra and LnS6 octahedra with Sr2+ ions residing between the layers. The compounds are transparent for IR radiation in the range 3200–1800 cm–1. 相似文献
7.
A. V. Ruseikina S. I. Kol’tsov O. V. Andreev L. A. Pimneva 《Russian Journal of Inorganic Chemistry》2017,62(12):1632-1637
The crystal structures of the first prepared EuLnAgS3 (Ln = Gd and Ho) compounds, which have two polymorphs, were determined by X-ray powder diffraction. α-EuLnAgS3 phases are isostructural to BaErAgS3 (monoclinic crystal system, space group C2/m): a = 17.3168(10) Å, b = 3.9683(2) Å, c = 8.3174(4) Å, β = 103.94° (EuGdCuS3); a = 17.1729(12) Å, b = 3.9367(3) Å, c = 8.2905(6) Å, β = 103.9° (EuHoCuS3). β-EuLnAgS3 phases belong to the AgBiS2 structure type (cubic crystal system, space group Fm-3m): a = 5.739(2) Å (EuGdCuS3) and a = 5.678 Å (EuHoCuS3). In the α-EuLnAgS3 crystal structure, LnS6 octahedra and AgS5 trigonal bipyramids share edges to form a three-dimensional (3D) structure with channels accommodating Eu2+ ions. A decrease in Ln3+ ionic radius gives rise to the crystal-chemical contraction of the 3D structure. 相似文献
8.
I. G. Fomina Zh. V. Dobrokhotova G. G. Aleksandrov M. A. Kiskin M. A. Bykov V. N. Ikorskii V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2007,56(9):1722-1730
The solid-state thermal decomposition of the dinuclear pivalate complexes LM(μ-OOCR)4ML, both those synthesized earlier (M = MnII, FeII, or CoII; L = 2,6-(NH2)2C5H3N)) and new complexes (M = CuII; L = 2,6-(NH2)2C5H3N or (2-NH2)(6-CH3)C5H3N), was studied by differential scanning calorimetry and thermogravimetry. The decomposition of the CoII complexes is accompanied by the aggregation to form the volatile octanuclear complex Co8(μ4-O)2(μn-OOCCMe3)12 (n = 2 or 3), whereas the thermolysis of the MnII, FeII, and CuII complexes is destructive, the phase composition of the decomposition products being substantially dependent on the nature
of metal and the α substituent R in the apical organic ligand. 相似文献
9.
Bin Peng Hui Chao Bin Sun Feng Gao Liang-Nian Ji Jian Zhang 《Transition Metal Chemistry》2007,32(2):271-277
Two novel cobalt(III) mixed-polypyridyl complexes
[Co(bpy)2(dpta)]3+ and [Co(bpy)2(amtp)]3+ (bpy = 2,2′-bipyridine, dpta = dipyrido-[3,2-a;2′,3′-c]-thien-[3,4-c]azine, amtp = 3-amino-1,2,4-triazino[5,6-f]-1,10-phenanthroline)
have been synthesized and characterized. The interaction of CoIII complexes with calf thymus DNA was investigated by spectroscopic and viscosity measurements. Results suggest that the two
complexes bind to DNA via an intercalative mode. Moreover, CoIII complexes have been found to promote the photocleavage of plasmid DNA pBR322 under irradiation at 365 nm. The mechanism studies
reveal that hydroxyl radical (OH•) is likely to be the reactive species responsible for the cleavage of plasmid DNA by [Co(bpy)2(dpta)]3+ and superoxide anion radical (O
2
•−
) acts as the key role in the cleavage reaction of plasmid DNA by [Co(bpy)2(amtp)]3+. 相似文献
10.
I. G. Fomina Zh. V. Dobrokhotova M. A. Kiskin G. G. Aleksandrov O. Yu. Proshenkina A. L. Emelina V. N. Ikorskii V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2007,56(9):1712-1721
The solid-state thermal decomposition of the tetrabridged dinuclear MnII, FeII, CoII, NiII, and CuII pivalate complexes with apical α-substituted pyridine ligands containing different substituents (2,3-dimethylpyridine or
quinoline) was studied by differential scanning calorimetry and thermogravimetry. The decomposition of the CoII complexes is accompanied by the aggregation to form the volatile octanuclear complex Co8(μ4-O)2(μn-OOCCMe3)12, where n = 2 or 3, whereas the thermolysis of the MnII, FeII, NiII, and CuII complexes is accompanied by the degradation of the starting compounds, the phase composition of the decomposition products
being substantially dependent on the nature of metal and the apical organic ligand.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1650–1659, September, 2007. 相似文献
11.
Phase equilibria in the systems SrS-Cu2S-Ln2S3 (Ln = La or Nd) have been studied along the isothermal section at 1050 K and vertical sections CuLnS2-SrS and Cu2S-SrLnCuS3, which are partially quasibinary joins. Compounds SrLnCuS3 with Ln = La or Nd have been synthesized for the first time. They crystallize in orthorhombic space group Pnma, the BaLaCuS3 structure type, with the following unit cell parameters: for SrLaCuS3, a = 1.1157(2) nm, b = 0.41003(6) nm, c = 1.1545(2) nm; for SrNdCuS3, a = 1.1083(1) nm, b = 0.40887(7) nm, c = 1.1477(2) nm. Noticeable homogeneity regions for SrLnCuS3 are not found. The compounds melt congruently by the reaction SrLnCuS3 ? SrS + L at 1365 K for SrLaCuS3 and 1400 K for SrNdCuS3. The tie-lines at 1050 K in the systems SrS-Cu2S-Ln2S3 radiate from SrLnCuS3 toward phases SrS, Cu2S, CuLnS2, and SrLn2S4, lying between the phases CuLnS2 and compositions from the γ-Ln2S3-SrLn2S4 solid-solution field. Eutectics are formed between the compounds CuLaS2 and SrLaCuS3 at 21.0 mol % SrS, T = 1345 K; between the compounds CuNdS2 and SrNdCuS3 at 31.0 mol % SrS, T = 1310 K; and between the phases Cu2S and SrLnCuS3 at 14.0 mol % SrLaCuS3, T = 1075 K and 8.0 mol % SrNdCuS3, T = 1055 K. 相似文献
12.
《Polyhedron》1988,7(1):79-81
The air and moisture stable complexes [Ln{HB(C3N2H3)3}2{MeC(O)CHC(O)Me}] (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Lu, Y), have been prepared and characterized. The molecular structures of the compounds with Ln = Ce and Yb reveal that a substantial distortion of the coordination geometry found for Ce3+ is necessary to allow the ligand set to accommodate the smaller Yb3+ ion. 相似文献
13.
V. V. Popov V. F. Petrunin S. A. Korovin A. P. Menushenkov O. V. Kashurnikova R. V. Chernikov A. A. Yaroslavtsev Ya. V. Zubavichus 《Russian Journal of Inorganic Chemistry》2011,56(10):1538-1544
The formation of (Ln3+)2(M4+)2O7 (Ln = Gd, Dy; M = Zr, Hf) nanocrystallites obtained by annealing mixed hydroxides LnM(OH)7 · nH2O (precursors) synthesized by coprecipitation has been studied by synchronous thermal analysis, X-ray diffraction (normal
and anomalous diffraction of synchrotron radiation), and EXAFS. In the systems under consideration, heat treatment of the
X-ray amorphous precursors leads to their dehydration, and at 600–700°C, nanocrystallites with an fcc structure of disordered
fluorite start forming. A further increase in temperature is accompanied by crystallite growth (CDD) and considerable change
in the local structure of the heat-treated compounds. The crystallization enthalpies and activation energies have been determined. 相似文献
14.
Lanthanide(II) Complexes Supported by N,O‐Donor Tripodal Ligands: Synthesis,Structure, and Ligand‐Dependent Redox Behavior
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Julie Andrez Dr. Gülay Bozoklu Dr. Grégory Nocton Dr. Jacques Pécaut Dr. Rosario Scopelliti Dr. Lionel Dubois Dr. Marinella Mazzanti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15188-15200
The preparation and characterization of a series of complexes of the Yb and Eu cations in the oxidation state II and III with the tetradentate N,O‐donor tripodal ligands (tris(2‐pyridylmethyl)amine (TPA), BPA? (HBPA=bis(2‐pyridylmethyl)(2‐hydroxybenzyl)amine), BPPA? (HBPPA=bis(2‐pyridylmethyl)(3.5‐di‐tert‐butyl‐2‐hydroxybenzyl)amine), and MPA2? (H2MPA=(2‐pyridylmethyl)bis(3.5‐di‐tert‐butyl‐2‐hydroxybenzyl)amine) is reported. The X‐ray crystal structures of the heteroleptic Ln2+ complexes [Ln(TPA)I2] (Ln=Eu, Yb) and [Yb(BPA)I(CH3CN)]2, of the Ln2+ homoleptic [Ln(TPA)2]I2 (Ln=Sm, Eu, Yb) and [Eu(BPA)2] complexes, and of the Ln3+ [Eu(BPPA)2]OTf and [Yb(MPA)2K(dme)2] (dme=dimethoxyethane) complexes have been determined. Cyclic voltammetry studies carried out on the bis‐ligand complexes of Eu3+ and Yb3+ show that the metal center reduction occurs at significantly lower potentials for the BPA? ligand as compared with the TPA ligand. This suggests that the more electron‐rich character of the BPA? ligand results in a higher reducing character of the lanthanide complexes of BPA? compared with those of TPA. The important differences in the stability and reactivity of the investigated complexes are probably due to the observed difference in redox potential. Preliminary reactivity studies show that whereas the bis‐TPA complexes of Eu2+ and Yb2+ do not show any reactivity with heteroallenes, the [Eu(BPA)2] complex reduces CS2 to afford the first example of a lanthanide trithiocarbonate complex. 相似文献
15.
V. N. Krasil’nikov A. P. Tyutyunnik V. G. Zubkov I. F. Berger L. A. Perelyaeva I. V. Baklanova 《Russian Journal of Inorganic Chemistry》2010,55(9):1331-1338
Vanadium(V) complexes of general composition M3VO2(SO4)2 (M = Rb, Cs) were synthesized by a solid-state route. The individuality of the synthesized compounds was proved by X-ray and neutron diffraction, vibrational spectroscopy, and microscopic analysis. The X-ray diffraction patterns of M3VO2(SO4)2 were indexed to fit the monoclinic system (space group P2/c, Z = 4) with the following unit cell parameters: a = 11.6487(2) Å, b = 8.4469(2) Å, c = 12.1110(2) Å, β = 109.483(1)°, V = 1123.43 Å3 (Rb); a = 12.0546(3) Å b = 8.7706(2) Å, c = 12.6496(3) Å, β = 109.843(2)°, V = 1257.99 Å3 (Cs). In the crystal structure of M3VO2(SO4)2, [VO2(SO4)2]3? complex anions can be discerned in which the vanadium atom is surrounded by five oxygen atoms: two oxygen atoms form short terminal V–O bonds, and three oxygen atoms are from the two sulfato groups, one of which acts as a monodentate ligand and the other acts as a bidentate chelating ligand. 相似文献
16.
Syntheses and Crystal Structures of New Alkali Metal Rare‐Earth Tellurides of the Compositions KLnTe2 (Ln = La, Pr, Nd, Gd), RbLnTe2 (Ln = Ce, Nd) and CsLnTe2 (Ln = Nd) Of the compounds ALnQ2 (A = Na, K, Rb, Cs; Ln = rare earth‐metal; Q = S, Se, Te) the crystal structures of the new tellurides KLaTe2, KPrTe2, KNdTe2, KGdTe2, RbCeTe2, RbNdTe2, and CsNdTe2 were determined by single‐crystal X‐ray analyses. They all crystallize in the α‐NaFeO2 type with space group R3¯m and three formula units in the unit cell. The lattice parameters are: KLaTe2: a = 466.63(3) pm, c = 2441.1(3) pm; KPrTe2: a = 459.73(2) pm, c = 2439.8(1) pm; KNdTe2: a = 457.83(3) pm, c = 2443.9(2) pm; KGdTe2: a = 449.71(2) pm, c = 2443.3(1) pm; RbCeTe2: a = 465.18(2) pm, c = 2533.6(2) pm; RbNdTe2: a = 459.80(3) pm, c = 2536.5(2) pm, and CsNdTe2: a = 461.42(3) pm, c = 2553.9(3) pm. Characteristics of the α‐NaFeO2 structure type as an ordered substitutional variant of the rock‐salt (NaCl) type are layers of corner‐sharing [(A+/Ln3+)(Te2—)6] octahedra with a layerwise alternating occupation by the cations A+ and Ln3+. 相似文献
17.
The reaction of 3,6-di-(3-methyl-pyridin-2-yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2O] generates a new ligand, N-(3-methyl-pyridin-2-yl)-formimidoyl-(3-methyl-pyridin-2-yl) hydrazone (L), and forms a new complex:
a mononuclear complex [Ce(L)(NO3)2 (H2O)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2) nm, c = 1.4572(3) nm, α= 102.13(2)°, β=
99.81(3)°, γ= 91.10(3)°, Z = 2, V = 1113.6(7) nm3, μ = 2.123 mm−1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2O molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism
of the metal assisted decomposition is discussed briefly. 相似文献
18.
Nizam M. El-Ashgar Issa M. El-Nahhal Mohamed M. Chehimi Michel Delamar Florence Babonneau Jacques Livage 《Journal of Sol-Gel Science and Technology》2007,41(1):3-10
A new insoluble solid functionalized ligand system bearing chelating ligand group of the general formula P-(CH2)3-N[CH2CONH(C6H4)NH2]2, where P represents [Si–O]
n
polysiloxane network, was prepared by the reaction of the immobilized diethyliminodiacetate polysiloxane ligand system, P-(CH2)3N(CH2CO2Et)2 with 1,2-diaminobenzene in toluene. 13C CP-MAS NMR, XPS and FTIR results showed that most ethylacetate groups (–COOEt) were converted into the amide groups (–N–C=O).
The new functionalized ligand system exhibits high capacity for extraction and removal of the metal ions (Fe3+, Co2+, Ni2+, Cu2+ and Zn2+) with efficiency of 95–97% after recovery from its primary metal complexes. This functionalized ligand system formed 1:1
metal to ligand complexes. 相似文献
19.
Zsolt Baranyai Ern Brücher Tímea Ivnyi Rbert Kirly Istvn Lzr Lszl Zkny 《Helvetica chimica acta》2005,88(3):604-617
Eu3+, Dy3+, and Yb3+ complexes of the dota‐derived tetramide N,N′,N″,N′′′‐[1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetrayltetrakis(1‐oxoethane‐2,1‐diyl)]tetrakis[glycine] (H4dotagl) are potential CEST contrast agents in MRI. In the [Ln(dotagl)] complexes, the Ln3+ ion is in the cage formed by the four ring N‐atoms and the amide O‐atom donor atoms, and a H2O molecule occupies the ninth coordination site. The stability constants of the [Ln(dotagl)] complexes are ca. 10 orders of magnitude lower than those of the [Ln(dota)] analogues (H4dota=1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid). The free carboxylate groups in [Ln(dotagl)] are protonated in the pH range 1–5, resulting in mono‐, di‐, tri‐, and tetraprotonated species. Complexes with divalent metals (Mg2+, Ca2+, and Cu2+) are also of relatively low stability. At pH>8, Cu2+ forms a hydroxo complex; however, the amide H‐atom(s) does not dissociate due to the absence of anchor N‐atom(s), which is the result of the rigid structure of the ring. The relaxivities of [Gd(dotagl)] decrease from 10 to 25°, then increase between 30–50°. This unusual trend is interpreted with the low H2O‐exchange rate. The [Ln(dotagl)] complexes form slowly, via the equilibrium formation of a monoprotonated intermediate, which deprotonates and rearranges to the product in a slow, OH?‐catalyzed reaction. The formation rates are lower than those for the corresponding Ln(dota) complexes. The dissociation rate of [Eu(dotagl)] is directly proportional to [H+] (0.1–1.0M HClO4); the proton‐assisted dissociation rate is lower for [Eu(H4dotagl)] (k1=8.1?10?6 M ?1 s?1) than for [Eu(dota)] (k1=1.4?10?5 M ?1 s?1). 相似文献
20.
《Journal of Coordination Chemistry》2012,65(4):333-344
Abstract The ligand exchange reaction between [M(phen)3]2+ and [M(DIP)3]2+ (where M is the same and M = FeII or NiII, phen = 1,10-phenanthroline, DIP = 4,7-diphenyl-1,10-phenanthroline) has been investigated by reversed phase ion-paired chromatography (RP-IPC). The effect of pH and solvent on the ligand-exchange reaction is studied by monitoring the variation in chromatograms with time after mixing. The results have shown that the ligand exchange reaction between [M(phen)3]2+ and [M(DIP)3]2+ takes place in the pH range of 3–8 and the rate of reaction for nickel(II) complexes is about two times slower than that for iron(II) complexes. Experiments on the effect of various solvents on the ligand-exchange reaction have revealed that the rate of reaction is enhanced by the solvent in the following order: (CH3)2CO > CHCl3 ≥ CH2Cl2 > CH3CN > CH3OH. Elemental analysis and UV-visible spectroscopy confirmed that the products obtained from the ligand-exchange reaction are mixed-ligand complexes containing phen and DIP ligands, i.e., [M(phen)2(DIP)]2+ and [M(phen)(DIP)2]2+. 相似文献