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1.
The experimental electronic spectra of the Eu3+ ion in three groups of the Eu complexes (-diketonates, acetates, and nitrates) with the 1,10-phenanthroline derivatives were used to calculate the crystal field parameters for the model of the nearest environment of this ion with the C 2 point group symmetry. It was shown that these parameters can be used for estimating the coordination number of the metal cation and establishing the structural peculiarities.  相似文献   

2.
The complex formation of alicyclic ketones, viz., camphor, cyclohexanone, menthone, and cytisine, with the Eu(fod)3 chelate (fod is 7,7-dimethyl-1,1,1,2,2,3,3-heptafluorooctane-4,5-dione) in the ground and excited states was studied by chemiluminescence and kinetic luminescence spectroscopy, respectively. The stability constants and thermodynamic parameters of complex formation were determined. An increase in the stability of the electron-excited complexes [Eu(fod)3*·Ketone] is explained by the enhancement of the acceptor ability of the Eu3+ chelate due to an increase in the fraction of the covalent component caused by the involvement of 4f-orbitals. The results obtained give direct evidence for the effect of the 4f-shell excitation of Eu(fod)3 on complex formation due to the involvement of f-electrons in the chemical bonds.  相似文献   

3.
铕(Ⅲ)水杨酸邻菲咯啉三元配合物性质研究   总被引:4,自引:0,他引:4  
合成了Eu3+的水杨酸和邻菲咯啉三元配合物,其组成为Eu(Hsal)3phen,用IR,UV,XPS研究配合物的性质和成键特征.结果表明,Hsal-的羧基、phen的两个氮原子均与Eu3+离子呈双齿配位,形成配合物后芳香环上的共轭性减小.用循环伏安法研究了配合物在玻碳电极上的电化学行为,发现配合物的电化学可逆性比游离Eu3+离子差,不同底液对配合物的电化学行为有影响.  相似文献   

4.
A detail study on the Eu(fod)_3-catalyzed rearrangement of al-lylic esters was described. A significant effect of the substituentsat the allylic backbone was observed. The migrating tendencyof the alkoxyacetates was established in the order of p-CF_3C_6H_4CH_2OCH_2CO_2>MeOCH_2CO_2>PhCH_2OCH_2CO_2>p-MeOC_6H_4CH_2OCH_2CO_2.  相似文献   

5.
Formation thermodynamics of binary and ternary lanthanide(III) (Ln = La, Ce, Nd, Eu, Gd, Dy, Tm, Lu) complexes with 1,10-phenanthroline (phen) and the chloride ion have been studied by titration calorimetry and spectrophotometry in N,N-dimethyl-formamide (DMF) containing 0.2 mol-dm–3 (C2H5)4NClO4 as a constant ionic medium at 25°C. In the binary system with 1,10-phenanthroline, the Ln(phen)3+ complex is formed for all the lanthanide(III) ions examined. The reaction enthalpy and entropy values for the formation of Ln(phen)3+ decrease in the order La > Ce > Nd, then increase in the order Nd < Eu < Gd < Dy, and again decrease in the order Dy > Tm > Lu. The variation is explained in terms of the coordination structure of Ln(phen)3+ that changes from eight to seven coordination with decreasing ionic radius of the metal ion. In the ternary Ln3+-Cl-phen system, the formation of LnCl(phen)2+, LnCl2(phen)+, and LnCl3(phen) was established for cerium(III), neodymium(III), and thulium(III), and their formation constants, enthalpies, and entropies were obtained. The enthalpy and entropy values are also discussed from the structural point of view.  相似文献   

6.
The synthesis and structural features of some newly synthesized 1,10-phenanthroline complexes of p-hydroxyphenyl-and 3-methyl-4-hydroxyphenyltellurium trihalides (chlorides, bromides, and iodides) are reported. The resulting complexes have been subjected to elemental analyses, conductance and cryoscopic measurements, infra-red and proton magnetic resonance spectral studies. Solution studies reveal the weak to 1:1 electrolyte type behavior of these complexes in solution. Spectral studies indicate the linkage of phenanthroline to the tellurium atom through the nitrogen atoms. Central tellurium atom in these complexes is hexa-coordinated in an octahedral way.  相似文献   

7.
Complexation of sulfones (S) with the -diketonate Eu(Fod)3 (Fod–heptafluorodimethyloctanedione) in the ground and excited electronic states in benzene solutions was studied. The stability constants and thermodynamic parameters for the formation of complexes Eu(Fod)3 · S in the ground state (K, H 0, S 0) and Eu(Fod)3 * · S in the excited state (K*, H 0 *, S 0 *) were determined. The excitation of ff transitions of Eu(III) was found to enhance the stability of Eu(Fod)3 · S complexes, apparently due to an increase in the acceptor ability of the Eu(III) chelate. This fact confirms the involvement of the 4f orbital in the chemical bond formation. The compensation effect was observed for the thermodynamic parameters: S 0 = (2.9 ± 0.3) × 10–3H 0 + (35.0 ± 4.0) in the ground and S 0 * = (3.3 ± 0.3) × 10–3H 0 * + (49.0 ± 5.0) in the excited states of Eu(Fod)3. It was shown that electronic excitation of the 4f orbital of Eu(Fod)3 influences isotopic effects in complexation with sulfolanes.  相似文献   

8.
A detail study on the Eu(fod)3‐catalyzed rearrangement of allylic esters was described. A significant effect of the substituents at the allylic backbone was observed. The migrating tendency of the alkoxyacetates was established in the order of p‐CF3C6H4CH2OCH2CO2 > MeOCH2CO2 > PhCH2OCH2CO2 > p‐MeOC6H4CH2OCH2CO2.  相似文献   

9.
10.
邻菲咯啉合铜配合物与牛血清白蛋白的相互作用   总被引:1,自引:0,他引:1  
利用荧光光谱法研究了两种配合物,[Cu(phen)(L-Phe)(H2O)]ClO4(1)(L-Phe为L-苯丙氨酸根)和[Cu(phen)(Gly)(H2O)]ClO4·2.5H2O(2)(Cly为甘氨酸根),与牛血清白蛋白(BSA)的相互作用。结果表明,牛血清白蛋白的荧光强度随着配合物浓度的增大而逐渐降低,配合物(2)与BSA的结合常数大于配合物(1)与BSA的结合常数,牛血清白蛋白对配合物的结合位点数为1,荧光猝灭作用机理为静态猝灭.  相似文献   

11.
Mixed complexes of the copper(II) ion with 2,2′-dipyridyl or 1,10-phenanthroline and some aromatic, aliphatic and cycloalkane-1,1-dicarboxylic acids have been prepared and characterized. Infrared and electronic spectra are also reported and discussed. On the basis of spectral data two possible stereochemistries were suggested for the prepared complexes. The dependence of the electronic spectra of the complexes in aqueous and methanolic solutions on the addition of some high strength donor ligands has been also studied.  相似文献   

12.
7,7,8,8-四氰基对苯醌二甲烷与邻菲咯啉稀土配合物的合成和表征张明杰,聂玉敏,史志勤,张文胜,梁惠来(天津大学化学系天津300072)(天津大学电子工程系天津)关键词四氰基对苯酮二甲烷,邻菲咯啉,镧配合物,钕配合物,合成7,7,8,8-四氰基对苯...  相似文献   

13.
14.
Temperature dependences of the paramagnetic shifts induced by Eu(fod)3 in 1H NMR spectra of ethylene oxide in carbon disulphide solution are obtained in the temperature range from +40 to ? 100°C at 100 MHz and from +30 to ?60°C at 60 MHz. The influence of chemical exchange leads to a decrease of the observed paramagnetic shifts with decreasing temperature. It is shown that a modified Swift and Connick equation can be used to describe the observed dependences. Upper limits of the mean lifetimes of the Eu(fod)3-ethylene oxide adduct are τp < 1·7 × 10?8 s at 14 °C and τp < 1 × 10?8 s at 20 °C, respectively. The corresponding activation energy is equal to Va = 13·7 kcal/mol.  相似文献   

15.
选用常规Y沸石和经后处理法制备的多级孔Y沸石为主体,采用自由配体法将铜菲咯啉(CuPhen)配合物封装在不同Y沸石中,制备了CuPhen/Y复合催化材料。采用X射线衍射、TEM、紫外-可见光谱、N_2吸附-脱附、ICP和TG等手段对所制备复合催化材料的物化性质进行了较为详细的表征,并对封装在不同Y沸石主体中的铜配合物在不同尺寸大小反应底物中的催化氧化性能进行了比较研究。结果表明,在以双氧水为氧化剂的反应体系中,封装于多级孔Y沸石中的铜配合物在不同环烷烃氧化反应中的催化活性均高于封装在常规Y沸石中的催化活性,体现出多级孔Y沸石更为优越的主体性能。此外,同封装于常规Y沸石中的铜配合物一样,封装在多级孔Y沸石主体中的金属配合物催化剂也具有良好的稳定性。  相似文献   

16.
1,10-菲咯啉及其衍生物铜配合物的抗癌活性研究进展   总被引:1,自引:0,他引:1  
夏寺丰  鲁晓明 《化学通报》2011,(12):1096-1104
作为一种微量生命元素,铜在生物进程中扮演着重要角色,很多铜配合物呈现抑制癌细胞增殖的活性。本文论述了以1,10-菲咯啉及其衍生物为配体的铜配合物的抗癌活性研究进展,分析了其对DNA裂解的可能机理。对比顺铂类抗癌药物,展望了铜配合物作为抗癌药物的应用前景。  相似文献   

17.
IntroductionTherehasbeenconsiderableinterestinthecoordinationchemistryoflanthanidecomplexeswithcarboxylateligandsduetotheirpotentialapplicationinmolecularassembliesandluminescentprobesinsystemsofbiologicalrelevance .1 4 Ofthenumerouslanthanidecomplexesthathavebeenwidelystudied,5 9mostofthemarefoundtoexhibitavarietyofdimericorinfinitechainstructure.RecentlywehavereportedpolymericLu(POA) 3(phen)compoundinwhichlutetiumionsforminfinitechainalongtheb axisdirectionthroughthecoordinationofbridgingc…  相似文献   

18.
19.
Luminescence accompanying an impact mechanical treatment of solid particles of the complex of Eu(fod)3 (fod is 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dione) with dispiro(adamantane-1,2-dioxetane) (1) was discovered and studied. The luminescence has a complex structure, and its spectrum belongs to the excited EuIII ions. The emission of light is observed only in a mechanical mixture of the Eu(fod)3 with dioxetane1 and in their cocrystallized form, but not in the case of the components taken separately. The mechanism by which the impacts cause the luminescence is considered. It was shown that the luminescence is not triboluminescence, but is chemiluminescence induced by the decomposition of compound1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1159–1162, May, 1996.  相似文献   

20.
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