Synthesis,structure and catalytic activity of complexes [Ln(EDBP)_2(DME)Na(DME)_3](Ln=Er,Yb,Sm) for ring-opening polymerization of ε-caprolactone

Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well...     

Cluster—cracking Reaction,a New Method to Synthesize Unsymmetrical Dithiolate Complexes for the Study of Third—Order Nonlinear Optical Properties

A new coluster-cracking method to synthesize dithiolate metal complexes was reported and four unsymmetric complexes with formula(Me4N)2[M(Ln)(SPh)2](M=Cd and Zn,L1=dmit=1,3-dithiole-2-thione4-5,dithiolate,L2=dmid=1,3-dithiole-2-one-4,5-dithiolate,SPh=thiophenolate)(1-4)were characterized by elemental analysis,IR,UV NMR spectra and so on.The advantages of this method are summarized in two aspects:(1) the preparation is very convenient;(2) the reaction usually completed giving the product with high pruity.The crystal structure of 1 showed that the bond distances of Cd(Ⅱ）to the sulfur of the thiophenolate group are shorter than those of Cd(Ⅱ）to the sulfur of dmit,so that the thiophenolate group does not be replaced in the reaction and thmixed ligand complexes are the dominant produxts.The dmit complexes showed well third-order NLO properties,but not of the dmid complexes,although dmid is an analogue to dmit.     

CD Spectroscopic Study on the Molecular Recognition of Chiral Salen－Metal Complexes

The molecular recognition behavior of the chiral salen-metal complexes towards guest molecules, such as imidazole derivatives and amino-acid ester, was systematically investigated by means of circular dichroism (CD) spectra. The coordination numbers of the host-guest complexes as well as the recognition capability of the salen-metal complexes were explained by character and intensity analyses of the CD spectra.     

Meso-5，10，15，20-四-（对-甲氧基苯基）卟啉稀土氯化物的合成与表征

meso-Tetrakis-（p-methoxyphenyl）porphyrin rare earth chlorides, Ln（TMOPP）Cl （Ln： Dy, Ho, Tm, Yb, Lu and H2TMOPP： tetrakis-（p-methoxyphenyl）porphyrin）, were synthesized and characterized. Their composition, structure and properties were studied by elemental analyses, ultra-violet visible spectra, infrared spectra, luminescence spectra, molar conductances and thermal analysis. The four nitrogen atoms of the porphyrin are bonded to a central rare earth ion with four coordination numbers. The lanthanide ion lies above the porphyrin molecular plane and chloride ion is outside boundary of the coordination compound. Complexes are stable below 200℃ and do not contain small molecules （water or solvent）. Ultra-violet visible and infrared spectra were recorded and some of spectral bands were assigned. Surface photovoltaic spectroscopy （SPS） and electric-field induced surface photovoltaic spectroscopy （EFISPS） were measured. The spectral bands were assigned. The photovoltaic response is similar to the UV-visible absorption spectrum, therefore corresponding to analogous electron transition process.     

新型取代硅桥联茂稀土化合物的合成及在纳米级氢化钠助催化剂作用下高活性催化甲基丙烯酸甲酯聚合的研究

The synthesis and characterization of four new silicon-linked lanthanocene complexes with pendant phenyl groups on cyclopentadiene were reported. Based on the data of elemental analyses, MS and IR, the complexes were presumed to be unsolvated and dimeric complexes [Me2Si(C5H3CMe2C6H5)2LnC1]2 [Ln=Er (1), Gd (2), Sm (3), Dy (4)]. In conjunction with AlEt3 or sodium hydride as the co-catalyst, these complexes could efficiently catalyze the polymerization of methyl methacrylate (MMA). When the nanometric sodium hydride was used as a co-catalyst, the complexes were highly effective for the polymerization of MMA. At low temperature and in short time, in [MeESi(C5H3CMe2C6H5)2LnC1]2/NaH (nanometric) system, the polymer was obtained in more than 80% yield and the molecular weight was greater than 105. The activity reached that of organolanthanide hydride as a single-component catalyst. In ]MeESi(C5H3CMe2C6H5)2ErC1]2/Nail (nanometric) system, the effects of the molar ratio of MMA/catalyst and catalyst/co-catalyst, and the temperature on polymerization were studied.     

金刚烷胺邻香兰素Schiff碱稀土配合物的合成、表征及抗菌活性研究

The new solid complexes [LnL₂(NO₃)₂]NO₃ (L=C₁₈H₂₃NO₂, N-2-hydroxy-3-methoxy-benzaldehyde-1-aminoadamanantane, Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y) of rare earth nitrates with Schiff base derived from o-vanillin and adamantaneamine have been synthesized in non-aqueous system and characterized by elemental analysis, molar conductance, infrared spectra, ¹H NMR spectra, thermal analysis. The coordination modes of the bonding in these complexes were discussed and the possible structure were proposed. Every central Ln(Ⅲ) ion in the complexes coordinates with both two Schiff base ligands via four oxygen atoms of the phenol hydroxy groups and methoxy groups and two nitrates via their four oxygen atoms. Their coordination numbers are eight. In addition, the antibacterial activity of the Schiff base ligand and the complexes were studied.     

N，N′-苄基-1，2二胺合铜的合成和晶体结构及与DNA的相互作用

A ligand， (N，N′-dibenzylethane-1，2-diamine) (L)， and its complex with copper acetate was synthesized and characterized by some spectral analyses. The copper(Ⅱ) ion is six-coordinated and exhibites octahedral coordination geometry， the coordination atoms are four nitrogen atoms from two(L) ligands and two carboxyl oxygen atoms from two acetic acid groups， respectively. After studying the interaction of the complex with calf thymus DNA through UV and fluorescence spectra， we can find that there is a strong binding and a large affinity berween the complex and calf thymus DNA. CCDC: 649416.     

N,N′-苄基-1,2二胺合铜的合成和晶体结构及与DNA的相互作用(英文)

A ligand,(N,N′-dibenzylethane-1,2-diamine)(L),and its complex with copper acetate was synthesized and characterized by some spectral analyses.The copper ! ion is six-coordinated and exhibites octahedral coordination geometry,the coordination atoms are four nitrogen atoms from two(L) ligands and two carboxyl oxygen atoms from two acetic acid groups,respectively.After studying the interaction of the complex with calf thymus DNA through UV and fluorescence spectra,we can find that there is a strong binding and a large affinity berween the complex and calf thymus DNA.CCDC: 649416.     

Studies of a new series of ion-pair complexes [Mo(dtc)_4][Ln(dtc)_4] (Ln=La-Er,exp.Pm)

A new series of ion-pair complexes [Mo(dtc)4][Ln(dtc)4] (Ln=La-Er, exp. Pm) were synthesized from MoCl5, LnCl3 and Nadtc in anhydrous methanol. The crystal structures of the four complexes, [Mo(dtc)4][Ln(dtc)4] (Ln=Nd, Sm, Ho and Er) have been determined by X-ray diffraction. Spectroscopic properties of all these complexes are also discussed here.     

10种2-[(N-取代芳胺基)羰基]苯甲酸与Cr(Ⅲ)的配合物研究

Complexes of Cr(Ⅲ) with ten of substituted phthalanilic acids have been prepared and characterized by the basis of elemental analysis, infrared and electronic spectra and magnetic susceptibility. The ligand field parameters, e.g. 10Dq, LFSE, B, β, λ, g-have been evaluated from the spectral and magnetic data for all the complexes. The results show that coordination occurs though two oxygen atoms in amido and hydroxy of carboxylates and the complexes have octahedral structure.     

Synthesis, characterization and crystal structure of a 6,8,15,17-tetramethyldibenzo [b,i] (1,4,8,11)tetraaza (14)-annulene yttrium (III) complex

In this study, the sandwich complex of tmtaa, Y(tmtaa) (Htmtaa)·2THF (H₂tmtaa=6,8,15,17-tetramethyldibenzo [b,i] , respectively. The distances of the yttrium to the planes of the 4 nitrogen atoms for tmtaa and Htmtaa are 1.44 (2) and 1.51 (2) Å, respectively.     

SYNTHESES,CHARACTERIZATION AND CRYSTAL STRUCTURE OF TETRAMETHYLDIBENZOTETRAAZA[14]-ANNULENE ZINC(II) COMPLEXES CONTAINING AN AXIAL BASE

Abstract

The complexes of Zn(tmtaa) and Zn(tmtaa)L [H₂tmtaa = tetramethyldibenzotetraaza[14]-annulene; L = triethylamine, pyridine (Py) and p-dimethylaminopyridine (p-N(CH₃)₂Py)] were synthesized and characterized by IR, LTV, mass and NMR spectra as well as DSC measurements. The effects of different axial ligands (L) on the spectral properties of the complexes have been studied. The crystal structure of Zn(tmtaa)N(C₂H₅)3 was determined by X-ray diffraction. The crystal belongs to a monoclinic system and the space group is P2₁/n. The cell parameters are a = 11.134(2)A, b = 17.453(4)Å, c= 13.784(3)Å, ? = 106.19(3)°, Z = 4, R₁, =0.0336 and wR₂= 0.0805 for 4539 independent reflections with I <2σ(I). The zinc(II) is coordinated through four nitrogen atoms of tmtaa and a nitrogen of triethylamine to form a five-coordinate square-pyramidal structure. The average bond length of Zn for the four nitrogens of tmtaa is 2.050(2)Å and for a nitrogen of triethylamine is 2.188(2)Å. The displacement of the zinc to the plane of four nitrogens of tmtaa is 0.563(2)Å.     

Preparation and structures of some tetraazamacrocyclic complexes of In(III)

Treatment of the dibenzo-tetraaza macrocycle, C₂₂H₂₄N₄ (H₂tmtaa) (I), with triethylindium yields the diethylindium-macrocycle complex [Et₂In(Htmtaa)] (IV). On heating (IV) is converted quantitatively into the monoethyl complex [EtIn(tmtaa)] (V). A single crystal X-ray diffraction study on (V) shows the EtIn fragment to be bonded to the four planar nitrogen atoms of the macrocycle, with a square–pyramidal geometry around the metal. Reaction of the dilithio salt of (I), [Li₂(tmtaa)], with InCl₃ yields [ClIn(tmtaa)] (VI), and further reaction of (VI) with equimolar quantities of LiR [R=C₅H₅(Cp), Me, N(SiMe₃)₂, OSiMe₃] yields the corresponding [RIn(tmtaa)] derivatives [R=Cp (VII), Me (VIII), N(SiMe₃)₂ (IX), OSiMe₃ (X)]. An X-ray diffraction study on (VII) shows an η¹-bonded Cp group, with the metal atom also bound to the four nitrogen atoms of the tmtaa ligand.     

Synthesis, structure and catalytic activity of complexes [Ln(EDBP)2(DME)Na(DME)3](Ln=Er, Yb, Sm) for ring-opening polymerization of ?-caprolactone

Discrete ion-pair complexes [Ln(EDBP)₂(DME)Na(DME)₃] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2′-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH₂) and Ln(BH₄)₃·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1–3 can all be used as single component initiators for the ring-opening polymerization of ɛ-caprolactone.     

Tetrathiafulvalene-based lanthanide coordination complexes: Synthesis,crystal structure,optical and electrochemical characterization

The explorative lanthanide coordination chemistry of 4′,5′-bis-(propylthio)tetrathiafulvenyl[i]dipyrido[3,2-a:2′,3′-c]phenazine (TTF-dppz) is described. Thereby, four new Ln(III) complexes, [Ln(NO₃)₃(TTF-dppz)₂] with Ln(III) = Nd (1), Eu (2), Gd (3), Tb (4), have been prepared and characterized. An X-ray crystallographic study of [Gd(NO₃)₃(TTF-dppz)₂] (3) shows that the Gd(III) ion is coordinated to six oxygen atoms from three bidentate nitrate ligands and four nitrogen atoms from two bidentate TTF-dppz molecules forming a distorted bicapped square antiprism coordination geometry. The UV-vis spectra of the four Ln(III) complexes show very strong absorption bands in the UV region consistent with ligand centred electronic π-π* transitions and an intense broad absorption band in the visible region corresponding to a spin-allowed electronic π-π* ¹ILCT transition from the TTF-dppz ligand. Upon coordination, the ¹ILCT band of the free TTF-dppz ligand is bathochromically shifted. The electrochemical studies reveal that all complexes undergo two reversible oxidation and one (quasi)reversible reduction processes, ascribed to the successive oxidations of the TTF moiety and the reduction of the dppz unit, respectively. Moreover, the magnetic properties of complexes 3 and 4 are discussed.     

Complexes of erbium and lutetium bromides with carbamide: Synthesis and structures

The synthesis and data of the study of new complexes of erbium and lutetium bromides with carbamide, [Ln(Ur)₄(H₂O)₄]Br₃ (I and III) and [Ln(Ur)₆(H₂O)₂]Br₃ (II and IV) (Ln = Er and Lu), by IR spectroscopy and X-ray diffraction analysis are presented. For all four compounds, coordination with metal occurs through the oxygen atoms of the water and carbamide molecules. The coordination polyhedra of the Ln atoms are distorted square antiprisms. Coordination of four carbamide molecules does not change their planar structures. The bromide ions are not coordinated, existing in the external sphere. Many hydrogen bonds are observed in the structures of complexes of both types.     

Syntheses,characterization and thermal properties of the lanthanide complexes with 2-mercaptonicotinic acid and 1,10-phenanthroline

Fourteen new complexes with the general formula of Ln(Hmna)₃(phen) (H₂mna = 2-mercaptonicotinic acid and phen = 1,10-phenanthroline) were synthesized and characterized by elemental analyses, IR spectra and thermogravimetric analyses. In addition, molar specific heat capacities were determined by a microcalorimeter at 298.15 K. The IR spectra of the complexes showed that the Ln³⁺ coordinated with the oxygen atoms of H₂mna and the nitrogen atoms of phen. The complexes decomposed directly to oxides Ln₂O₃, CeO₂, Pr₆O₁₁, and Tb₄O₇ in one step. The values of molar specific heat capacities for fourteen solid complexes were plotted against the atomic numbers of lanthanide, which presented as “tripartite effect”. It suggested a certain amount of covalent character existed in the bond of Ln³⁺ and ligands, according with nephelauxetic effect of 4f electrons of rare earth ions. The article is published in the original.     

Solution Phase Chemistry of Lanthanide Complexes. 12. 1:1 and 1:2 Lanthanide Complexes with s-Carboxymethoxysuccinic Acid

Abstract

The solution phase coordination chemistry associated with 1:1 and 1:2 complexes of lanthanide ions with S-carboxymethoxysuccinic acid (CMOS) has been studied by spectroscopic means. The Tb(III) luminescence intensities and lifetimes were found to be sensitive towards the solution phase properties, as were the circularly polarized luminescence spectra of these complexes. It was found that below pH 6, Ln(CMOS) complexes were monomeric in nature and contained an average of 6 molecules of coordinated water. Above neutral pH, the Ln(CMOS)₂ complexes became self-associated into hydroxy-bridged, oligomeric species. The Ln(CMOS)₂ complexes were found to be oligomeric at all pH values, with ligand bridging taking place below neutral pH and hydroxy bridging taking place above neutral pH.     

稀土吲哚-3-乙酸和吲哚-3-丁酸配合物的合成、表征及成键特性研究

在乙醇水溶液体系中合成了8种新的稀土吲哚-3-乙酸和吲哚-3-丁酸配合物,其通式为Ln(lA)₃·2H₂O和Ln(IB)₃·2H₂O(Ln=La,Nd,Sm,Er;IA=C₁₀H₈NO₂;IB=C₁₂H₁₂NO₂)。用元素分析、电导测定、电子吸收光谱、红外光谱、X光电子能谱和热重-差热分析确定了配合物的组成和成键特性。