Synthesis and infrared and fluorescence spectra of rare earth complexes with a novel amide-based ligand

A novel amide-based open-chain crown ether, N,N'-1,3-propanediyl-bis[2-(benzyl -carbamoyl-methoxy)-benzamide] (L) and its solid complexes with rare earth nitrates and picrates have been prepared. The complexes were characterized by elemental analyses, molar conductivity and IR spectra. The fluorescence properties of the Eu(III) and Tb(III) complexes in solid and in organic solvents were studied. Under the excitation of ultraviolet light, these complexes exhibit characteristic emission of europium and terbium ions. The results show that the ligand favor energy transfers to the emitting energy level of Tb(III). Some factors that influence the fluorescent intensity were also discussed.     

Synthesis and infrared and luminescence spectra of rare earth complexes with a new hexapodal ligand

Solid complexes of rare earth nitrates and picrates with a new hexapodal ligand, 1,2,3,4,5,6-hexa{[(2'-benzylamino-formyl)phenoxyl]methyl}-benzene (L) have been prepared. These complexes were characterized by elemental analysis, IR and molar conductivity. At the same time, the luminescence properties of the Eu(III) and Tb(III) nitrates and picrates complexes in solid state were also investigated. Under the excitation of UV light, these complexes exhibited characteristic emission of europium and terbium ions. The influence of the counter anion on the luminescent intensity was also discussed.     

Synthesis and infrared and fluorescent spectra of rare earth complexes with a new amide ligand

Solid complexes of rare earth nitrates and picrates with a new amide ligand, 1,6-bis[(2'-benzylaminoformyl)phenoxyl]hexane (L) have been prepared. These complexes are characterized by elemental analysis, UV-vis spectra and IR spectra. The fluorescent and luminescent properties of the Eu(III) and Tb(III) nitrates and picrates complexes in solid state are also investigated. Under the excitation of UV light, these complexes except Tb(III) picrate complex exhibit characteristic emission of europium and terbium ions. The influence of the counter anion on the fluorescent intensity is also discussed.     

Studies on 1H NMR, infrared and fluorescence spectra of rare earth complexes with a new binaphthylamide

Solid complexes of lanthanide picrates with N,N-dibenzyl-2-[2'-[(dibenzylcarbamoyl)-methoxy]-[1,1']binaphthalenyl-2-yloxy]-acetamide (L), [Ln(pic)(3)L] (Ln = La, Nd, Eu, Gd, Tb, Dy, Y), have been prepared and characterized by elemental analysis, IR, 1H NMR, UV-Vis spectra and conductivity measurements. The fluorescence property of the europium complex in solid state and in CHCl(3), acetone, AcOEt and DMF was studied.     

Synthesis, characterization, cytotoxic activity and DNA binding Ni(II) complex with the 6-hydroxy chromone-3-carbaldehyde thiosemicarbazone

A new ligand L, 6-hydroxy chromone-3-carbaldehyde thiosemicarbazone, and its Ni(II) complex have been synthesized and characterized. The crystal structure of Ni(II) complex was determined by single crystal X-ray diffraction. Ni(II) complex and ligand L were subjected to biological tests in vitro using THP-1, Raji and Hela cancer cell lines. Compared with the ligand, Ni(II) complex showed significant cytotoxic activity against these three cancer cell lines. The interactions of Ni(II) complex and ligand L with calf thymus DNA were then investigated by spectrometric titration, ethidium bromide displacement experiments and viscosity measurements methods. The experimental results indicated that Ni(II) complex bound to DNA by intercalative mode via the ligand L. The intrinsic binding constants of Ni(II) complex and ligand L with DNA were (1.10 ± 0.65) × 10⁶ M⁻¹ and (1.48 ± 0.57) × 10⁵ M⁻¹, respectively.     

Synthesis, infrared and fluorescence spectra of lanthanide complexes with a new amide-based 1,3,4-oxadiazole derivative

A new amide-based 1,3,4-oxadiazole derivative ligand 2,5-bis[2-(N,N-diethyl-1'-oxopropylamide)phenyl]-1,3,4-oxadiazole (L) and its complexes, Ln(NO3)3L (Ln=La, Eu, Gd, Tb, Er), were synthesized. The complexes were characterized by elemental analysis, infrared spectra and conductivity. The lanthanide ions were coordinated by O atoms from CO. The fluorescence properties of Eu(NO3)3L and Tb(NO3)3L in the solid state and in different solvents were investigated. Under the excitation of UV light, these complexes exhibit characteristic fluorescence of europium and terbium ions. The solvent factors influencing the fluorescent intensity were discussed.     

稀土冠醚配合物的激光拉曼和红外光谱

本文观察了各个硝酸稀土与15-冠-5(1)、18-冠-6(2)生成的配合物的激光拉曼和红外光谱。配位体的C-O-C红外伸缩振动频率向红移,提供了两者发生配位的迹象。轻、重稀土配合物的不同光谱特征主要取决于配合物水合与否的不同空间构型。875cm~(-1)附近峰属于稀土离子与冠氧原子配位后的金属-氧环伸缩振动,它仅存在于轻稀土无水配合物中。     

直链醚-二甘肽型Schiff碱与稀土新配合物的合成、配 位作用与波谱

合成了稀土与四甘醇醛-二甘肽型Schiff碱(TAGLGL)形成的六种新配合物,在此配体中同时引入了C=N及HN—C＝O基团。经元素分析、光谱等表征,确定该类多核配合物组成为：[Ln3(TAGLGL)(NO3)7]·4H2O(Ln=La,Nd,Sm,Gd,Yb,Y)。以液体1^HNMR谱、固体高分辨^13CNMR等方法,并结合Gd(Ⅲ)配合物的EPR波谱着重探讨了配位作用,配位数和晶体场强等。     

Synthesis and infrared and fluorescent properties of rare earth complexes with a new aryl amide podand

Solid complexes of rare earth nitrates and picrates with a new aryl amide podand, 1,4-bis{[(2'-benzylamino-formyl)phenoxyl]methyl}-naphthaline (L) were synthesized. The complexes were characterized by elemental analysis, IR and molar conductivity measurements. At the same time, the fluorescent properties of the Eu(III) and Tb(III) nitrates and picrates complexes in solid state were also investigated. Under the excitation, these complexes exhibited characteristic emissions of europium and terbium ions. The counter anion factor influencing the fluorescent intensity was also discussed.     

Synthesis,spectral and antimicrobial studies of rare earth metal complexes with Schiff-base hydrazone containing quinoline moiety

The synthesis and characterization of lanthanide(III) complexes with the Schiff-base hydrazone, o-hydroxyacetophenone-7-chloro-4-quinoline, (HL) are reported. The complexes were characterized by different physicochemical methods: mass spectrometry, ¹H NMR, ¹³C NMR, and IR, UV-visible, molar conductance and magnetic studies. They have the stoichiometry [Ln(L)₂(NO₃)]·nH₂O where Ln = La(III), Pr(III), Nd(II), Sm(III), Eu(III) and n = 1–3. The spectra of the complexes were interpreted by comparison with the spectrum of the free ligand. The Schiff-base ligand and its metal complexes were tested against one stain Gram +ve bacteria (Staphylococcus aureus), Gram ?ve bacteria (Escherichia coli), and Fungi (Candida albicans). The tested compounds exhibited high antimicrobial activities     

Synthesis, structure and spectroscopic properties of rare earth complexes with a new aryl amide 2,2'-bipyridine derivative

Solid complexes of rare earth nitrates and picrates with a new aryl amide ligand 3.3'-bis(benzylamido)-2,2'-bipyridine (L) were synthesized and characterized by elemental analysis, IR and molar conductivity measurements. The molecular structures of the complex [TbL(2)(NO(3))(3)H(2)O].2H(2)O have been determined by single-crystal X-ray diffraction. The fluorescent properties of the Eu(III) and Tb(III) nitrates and picrates complexes in solid state were also investigated in detail. Under the excitation, these complexes exhibited characteristic emissions of europium and terbium ions. It is worth noting that the nature of the anion has a great effect upon the composition of the complexes as well as emission properties of them.     

Synthesis,structure, and character of two rare earth carboxylic acid complexes

Two rare earth carboxylic acid complexes, [Sm(MeBA)₃(2,2′-bipy)]₂·2(2,2′-bipy) (MeBA = 3-methylbenzoic acid; 2,2′-bipy = 2,2′-bipyridine) (1) and [Pr(MeBA)₃(H₂O)₂]_n?n(4,4′-bipy) (4,4′-bipy = 4,4′-bipyridine) (2), have been synthesized under hydrothermal conditions and structurally determined by single-crystal X-ray diffraction. Compound 1 is a dimer and further assembles into an infinite chain, two-dimensional net and three-dimensional supramolecular structure via weak π–π and C–H···π interactions. Some 2,2′-bipy coordinates with Sm and some exist by non-covalent C–H···π interactions. Compound 2 is a 1D infinite chain structure, with adjacent 1D chains connected into a 2D layer structure by O–H···N hydrogen bonds. The two complexes were characterized by elemental analyses, IR, photoluminescence, and TGA. In order to illustrate subtle structural characteristics of intermolecular interactions and magnetic sensitivity of the complex, 2D-IR correlation spectra (2D-IR COS) under magnetic perturbation for 1 were performed.     

稀土与脂肪族Schiff碱多核配合物的合成及波谱

在形成多核配合物的诸条件中,认为减小空间位阻颇为重要,设计的直链脂肪族的四甘醇醛与甘氨酸缩合形成的Schiff碱(TAGL)为此提供了有利的条件,且成功地获得了它与稀土离子反应形成的三核配合物(Ln:L=3:1):[Ln~3(TAGL)(NO~3)~7]CH~3OH·nH~2O(Ln=La,Nd,Sm,n=1;Ln=Gd,Dy,Yb,Y,n=2)。以元素分析,IR,NMR等确证其组成,根据EPR谱探讨了Gd(III)配合物的晶体场强,同时见到该类脂肪族Schiff碱及其配合物中δ~H~C~=~N的质子谱向高场明显位移至～5.10。     

Synthesis and infrared and fluorescence spectra of new europium and terbium polynuclear complexes with an amide-based 1,10-phenanthroline derivative

An amide-based 1,10-phenanthroline (phen) derivative and its complexes with europium(III) and terbium(III) ions were synthesized. The complexes were characterized by elemental analysis, infrared spectra and conductivity. The europium and terbium ions were coordinated by O atoms of C=O, Ar-O-C and N atoms of phen. The fluorescence properties of the complexes in THF, dioxane, MeCN and DMF were investigated. Under the excitation of UV light, these complexes exhibited characteristic fluorescence of europium and terbium ions. The solvent factors influencing the fluorescent intensity were discussed.     

Synthesis and spectroscopic properties of rare earth picrate complexes with a new biphenylamide

The new ligand N-benzyl-2-{2'-[(benzyl-ethyl-carbamoyl)-methoxy]-biphenyl-2-yloxy}-N-ethyl-acetamide (L) and its complexes of rare earth picrates were synthesized. The complexes were characterized by elemental analysis, IR, UV-vis spectra and conductivity measurements. The fluorescence properties of the europium complex in solid state and in CHCl(3), ethyl acetate, acetone, acetonitrile and DMF were investigated. Under the excitation, the europium complex exhibited characteristic emissions of europium. The lowest triplet state energy level of the ligand indicates that the triplet state energy level of the ligand matches better to the resonance level of Eu(III) than Tb(III) ion.     

Synthesis, crystal structure, antioxidation and DNA-binding properties of the Ln complexes with 1-phenyl-3-methyl-5-hydroxypyrazole-4-carbaldhyde-(benzoyl)hydrazone

Two lanthanide complexes (Ln = La, Pr) with a PMFP Schiff-base, 1-phenyl-3-methyl-5-hydroxypyrazole-4-carbaldhyde-(benzoyl)hydrazone (H₂L) were synthesized and characterized. The crystal structure of the La complex was determined by single-crystal X-ray diffraction, the coordination polyhedron is a tricapped trigonal prism configuration with the nine-coordinate atoms composed of three nitrogens and six oxygens from three ligands. The complex crystallized in the monoclinic lattice with a space group P2/c. Electronic absorption titration spectra, fluorescence titration spectra, EtBr competitive experiment, viscosity measurement and CD spectra indicate that all the complexes can strongly bind calf thymus DNA, presumably via groove binding and intercalation mechanism. Furthermore, investigations of antioxidation properties show that all the complexes have some scavenging effects for hydroxyl radicals.     

稀土硝酸盐与2,6-二乙酰吡啶双缩苯甲酰肼配合物的合成和结构

2,6-二乙酰吡啶双缩萃甲酰肼(DAPBH)的过渡金属配合物的研究已见诸文献, 它的稀土盐的配合物仅有La(DAPBH)(NO3)3的十一配位分子结构的简报。考虑到镧系收缩的影响, 从镧到镥, 离子的配位空间减少和水合能增加, 它们的配合物将有不同的配位结构, 因此, 本文合成了部份稀土硝酸盐的配合物, 并对镱的配合物进行了单晶结构分析。     

Synthesis and fluorescence properties of rare earth (Eu3+ and Gd3+) complexes with alpha-naphthylacetic acid and 1,10-phenanthroline

Rare earth binary complex Eu(NNA)3 (NNA, alpha-naphthylacetic acid), ternary complex Eu(NNA)3.phen (phen, 1,10-phenanthroline) and a series of dinuclear complexes with different mole ratios of Eu3+ to Gd3+ were synthesized. Many advanced approaches, such as element analysis, FTIR spectra, TG and DTA analysis, were used to determine the composition and structure of binary and ternary complex. Moreover, their fluorescence properties were studied by fluorescent spectra and lifetimes. The fluorescence spectra and decay curves of dinuclear complexes indicated that the fluorescence emission intensity was enhanced and the fluorescence lifetime was prolonged by Gd3+. The dinuclear complexes show the best properties when the mole ratio of Eu3+ to Gd3+ is 6:4. A new parameter Y, which was used to evaluate the effect of Gd3+, was introduced. In addition, the relationship of Y value and mole fraction of Gd3+ was analyzed by mathematical software. The results showed that Y value decreased by single exponential mode when the content of Gd3+ decreased.     

新型稀土配合物的合成表征及EXAFS研究

合成了五种新的稀土配合物RE2(NO3)6L2.nH2O, 其中L为一新的含β-双酮和Schiff-base配体, 1, 5-双(1'-苯基-3'-甲基-5'-吡唑啉酮-4')-1-(4'-氨基丁烷-1'-亚胺基)-5-戊酮, RE=Sm, Eu, Gd, Dy, Ho。对配合物进行了质谱、FTIR、变温红外、EXAFS等研究。结果表明: 配合物为双核结构; 配合物中NO3^-以离子型、单齿及双齿同时存在; 配体L中的C=O, C=N及NH2均参与配位; 稀土离子的总配位数为8, 双配位层分别为2个氮和6个氧, RE-N距离在0.230~0.240nm, RE-O0.240~0.250nm。     

稀土谷胱甘肽配合物红外和Raman光谱研究

谷胱片肽是广泛存在于体内的重要三肽, 在体内主要以还原型(GSH)存在. GSH不但是清除体内过氧化物的还原剂, 而且与某些金属的配合物具有酶活性. 随着稀土的广泛应用, 其生物效应已引起关注. 了解稀土与GSH的配合物结构和性质, 将有利于了解稀土在体内的代谢和作用. 本文合成了十五种稀土与GSH的固体配合物,用IR和Raman光谱研究了配体在配合物中的变化及与稀土的配合位置.