共查询到20条相似文献,搜索用时 13 毫秒
1.
A new fluorogenic sensor 1 capable of illustrating metal ion-triggered FRET changes has been synthesized. Based on the FRET changes, 1, bearing coumarin-fluorescein moieties, provides a selective sensor for Cu2+ and Hg2+ ions for experiments implemented in aqueous media with a chloride counter anion. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(18):2075-2081
The hydrothermal reactions of Nd(ClO4)3·6H2O, Gd(ClO4)3·6H2O, Dy(ClO4)3·6H2O, Er(ClO4)3·6H2O with 1,3-dicyanobenzene, give rise to four one-dimensional rare earth-based coordination polymers: [M(3-CNC6H4COO)3(H2O)2] n (where M?=?Nd (1), Gd (2), Dy (3), Er (4), 3-CNC6H4COO?=?3-cyanobenzoato), respectively. Their solid-state structures have been characterized by X-ray single-crystal diffraction studies. The results show that 1,3-dicyanobenzene hydrolyzed to give 3-cyanobenzoato under hydrothermal condition, and the four complexes are isomorphous. Crystal data for 1: triclinic, space group P-1, a?=?9.4063(19), b?=?11.485(2), c?=?12.616(3)?Å, α?=?66.38(3), β?=?74.01(3), γ?=?86.96(3)°, V?=?1197.9(4)?Å3, Z?=?1, D c?=?1.704?Mg?m?3; for 2: triclinic, space group P-1, a?=?9.3712(19), b?=?11.446(2), c?=?12.627(3)?Å, α?=?65.86(3), β?=?73.89(3), γ?=?86.84(3)°, V?=?1184.8(4)?Å3, Z?=?1, D c?=?1.759?Mg?m?3; for 3: triclinic, space group P-1, a?=?9.3425(19), b?=?11.432(2), c?=?12.703(3)?Å, α?=?65.28(3), β?=?73.80(3), γ?=?86.86(3)°, V?=?1180.6(4)?Å3, Z?=?1, D c?=?1.780?Mg?m?3; for 4: triclinic, space group P-1, a?=?9.3425(19), b?=?11.432(2), c?=?12.703(3)?Å, α?=?65.28(3), β?=?73.80(3), γ?=?86.86(3)°, V?=?1180.6(4)?Å3, Z?=?1, D c?=?1.7794?Mg?m?3. The fluorescence emission spectra of compounds 1 to 4 are also reported. 相似文献
3.
Ralf Knapp Ralf Knapp Steffen Kelch Oliver Schmelz Matthias Rehahn 《Macromolecular Symposia》2003,204(1):267-286
Synthetic strategies are presented for the preparation of readily soluble ruthenium(II) coordination polymers of high molecular weight. The constitutional homogeneity of the polymers is proved using high-resolution NMR spectroscopy, and their molar masses are estimated from 1H NMR spectra, viscosity data and SAXS investigations. The polymers are shown to be conformationally rigid, and to form either densely packed coils or rods. It is mainly this difference in shape which causes the very specific properties of the respective polyelectrolytes in the solid state as well as in dilute solution. Finally, the UV-vis absorption spectra of some of these materials are presented. 相似文献
4.
Five two-dimensional divalent cobalt coordination polymers containing 4,4′-bipyridine (bpy) and substituted or unsubstituted glutarate ligands have been prepared hydrothermally and structurally characterized by single-crystal X-ray diffraction. [Co(mg)(bpy)]n (1, mg=3-methylglutarate) forms a (4,4) rhomboid grid structure based on the connection of {Co2(CO2)2} dimeric units. Using the more sterically encumbered ligands 3,3-dimethylglutarate (dmg) and 3-ethyl, 3-methylglutarate (emg) generated {[Co(dmg)(bpy)(H2O)]·2H2O}n (2) and {[Co(emg)(bpy)(H2O)]·H2O}n (3), respectively. These complexes manifest {Co(CO2)}n chains linked into 2-D by aliphatic dicarboxylate and bpy ligands. The “tied-back” substituted glutarate ligand 1,1-cyclopentanediacetate (cda) afforded [Co(cda)(bpy)]n (4), and the unsubstituted glutarate (glu) generated [Co(glu)(bpy)]n (5), both of which exhibit a topology similar to that of 1. The magnetic properties of complexes 1-4 were analyzed successfully with a recently developed phenomenological chain model accounting for both magnetic coupling (J) and zero-field splitting effects (D), even though 1 and 4 contain isolated, discrete {Co2(CO2)2} dimers. The D parameter in this series varied between 21.8(8) and 48.0(9) cm−1. However weak antiferromagnetic coupling was observed in 1 (J=-2.43(4) cm−1) and 4 (J=−0.89(2) cm−1), while weak ferromagnetic coupling appears to be operative in both 2 (J=0.324(5) cm−1) and 3 (J=0.24(1) cm−1). 相似文献
5.
Camila B. Pinto Leonardo H. R. Dos Santos Bernardo L. Rodrigues 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):707-716
Properties related to the size and shape of Hirshfeld surfaces provide insight into the nature and strength of interactions among the building blocks of molecular crystals. In this work, we demonstrate that functions derived from the curvatures of the surface at a point, namely, shape index (S) and curvedness (C), as well as the distances from the surface to the nearest external (de) and internal (di) nuclei, can be used to help understand metal–ligand interactions in coordination polymers. The crystal structure of catena‐poly[[[(1,10‐phenanthroline‐κ2N,N′)copper(II)]‐μ‐4‐nitrophthalato‐κ2O1:O2] trihydrate], {[Cu(C8H3NO6)(C12H8N2)]·3H2O}n, described here for the first time, was used as a prototypical system for our analysis. Decomposition of the coordination polymer into its metal centre and ligand molecules followed by joint analysis of the Hirshfeld surfaces generated for each part unveil qualitative and semi‐quantitative information that cannot be easily obtained either from conventional crystal packing analysis or from Hirshfeld surface analysis of the entire polymeric units. The shape index function S is particularly sensitive to the coordination details and its mapping on the surface of the metallic centre is highly dependent on the nature of the ligand and the coordination bond distance. Correlations are established between the shape of the Hirshfeld surface of the metal and the geometry of the metal–ligand contacts in the crystals. This could be applied not only to estimate limiting coordination distances in metal–organic compounds, but also to help establish structure–property relationships potentially useful for the crystal engineering of such materials. 相似文献
6.
The ongoing search for new electroactive materials for next-generation redox flow batteries has within the last decade encompassed metal–ligand coordination chemistry. Here, we review the handful of metal coordination complexes proposed as redox flow battery electrolytes. We highlight examples with careful ligand design, driving research towards higher energy density storage materials. Metal coordination complexes designed to be highly soluble not only in the initial redox state but also in all charged states accessed during the battery cycle give particularly impressive performances. Optimisation of flow cell conditions for metal coordination complexes remains largely unexplored, with most complexes screened in nonideal H-cell experiments with little investigation into membrane and electrode materials. 相似文献
7.
《Mendeleev Communications》2022,32(1):105-108
A mixed-metal 1D coordination polymer [CaCu(HBTC)2(H2O)8]n (where H3BTC – benzene-1,3,5-tric arboxylic acid) was obtained in a solvothermal synthesis of a well-known copper-containing metal–organic framework [Cu3(BTC)2(H2O)3]n (HKUST-1) in autoclaves 3D-printed from commercial polypropylene. This material was a source of calcium ions, apparently, leaking from a colorant (calcium carbonate) promoted by glacial acetic acid as a modulator used to produce large single crystals of HKUST-1. This finding was confirmed by elemental analysis and a model experiment that resulted in a new calcium-based 1D coordination polymer [Ca(H2BTC)2(H2O)5]n under the same solvothermal conditions with no copper or calcium salts put into a 3D-printed autoclave. 相似文献
8.
Katerina N. LazarouVassilis Psycharis Aris TerzisCatherine P. Raptopoulou 《Polyhedron》2011,30(6):963-970
Reactions of copper(II) sources with 1,2-bis(4-pyridyl)ethane (bpe) yielded metal-organic networks with diverse topologies and dimensionalities. Compounds [Cu(bpe)2(dmf)2]n(ClO4)2n·2ndmf (1·2ndmf), [Cu(bpe)2(dmf)2]n(ClO4)2n·3.5ndmf (2·3.5ndmf), [Cu(bpe)2(NO3)2]n·2nH2O (4·2nH2O) and [Cu2(bpe)(O2CMe)4]n·0.7nH2O (5·0.7nH2O) have been isolated by altering the copper(II) source, the reaction solvent and the crystallization process. Compounds 1·2ndmf and 2·3.5ndmf consist of cationic [Cu(bpe)2(dmf)2]2+ repeating units assembled to 1D and 2D (4,4) networks, respectively, and represent supramolecular isomers due to the conformational isomerism of the bridging bpe molecules. Compound 4·2nH2O consists of neutral mononuclear [Cu(dpe)2(NO3)2] repeating units assembled to inclined interpenetrating (4,4) sheets describing an overall entanglement that is 3D in nature, and compound 5·0.7nH2O consists of neutral dinuclear repeating units assembled to cross-linked 1D chains. 相似文献
9.
不同化学环境对Er^3+离子的配位场能级结构的影响 总被引:1,自引:0,他引:1
首次在C3v点群对称汤中,运用双层点电荷配位场(DSCPCF)模型计算了CS3Y2I9晶体中Er^3 离子的59个配位场能级,与实验得到的能级比较,其均方根偏差为24.89cm^-1,而用点电荷配位场(PCF)模型计算的均方根偏差为29.08cm^-1,这说明双层点电荷配位场模型能更好地符合实验结果。同时,详细地分析CsLu2,Cs3Lu2Br9,Cs3Y2I9晶体中Er^3 离子能级结构的变化,由于Er^3 -X^-键共价性的增强,使Er^3 离子的能级重心发生红移,Cl→Br→I的配位场能级的分裂程序减小。 相似文献
10.
Rafika Bouchene Sofiane Bouacida 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(2):120-127
Two new coordination polymers, namely poly[[(3‐aminopyrazin‐4‐ium‐2‐carboxylate‐κ2N1,O)di‐μ‐chlorido‐cadmium(II)] monohydrate], {[CdCl2(C5H5N3O2)]·H2O}n, (1), and poly[2‐amino‐3‐carboxypyrazin‐1‐ium [(3‐aminopyrazine‐2‐carboxylato‐κ2N1,O)di‐μ‐chlorido‐cadmium(II)] monohydrate], {(C5H6N3O2)[Cd(C5H4N3O2)Cl2]·H2O}n, (2), have been synthesized from the reaction of cadmium(II) chloride and 3‐aminopyrazine‐2‐carboxylic acid (Hapca) under mild conditions in acidic media. The two coordination polymers have been characterized by single‐crystal X‐ray diffraction and show chloride‐bridged zigzag chains with octahedrally coordinated metal ions, where Hapca acts as a bidentate ligand via the π‐conjugated N atom and a carboxylate O atom. The chains are further interconnected via noncovalent interactions into three‐dimensional supramolecular networks. The dominant H…O and H…Cl interactions for both compounds were quantified using Hirshfeld surface analysis. The thermal stability and topological analysis of the two‐dimensional networks of (1) and (2) are also discussed. 相似文献
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12.
Investigation of the CuCl2/H2Memal/L (H2Memal = methylmalonic acid, L = 1,10-phenanthroline or 2,2′-bipyridine) reaction system in MeOH and various molar ratios has lead to the isolation of two one-dimensional coordination polymers presenting the [Cu(L)(Memal)] repeating unit (1, L = 1,10-phen; 2, L = 2,2′-bpy). The Memal2− ligand adopts the bidentate [chelating] + unidentate coordination mode between the CuII ions. Magnetic susceptibility measurements on 1 and 2 indicated the existence of weak ferromagnetic intrachain interactions and X-band EPR spectra from powdered samples of 1 and 2 are consistent with the stereochemistry of the CuII ions and with the presence of weak exchange interactions. 相似文献
13.
以三聚氰胺(MEL)为模板分子、α-甲基丙烯酸(MAA)为功能单体、乙二醇二甲基丙烯酸酯(EGDMA)为交联剂、Fe3O4@SiO2磁性材料为载体,制备得到三聚氰胺磁性表面分子印迹聚合物(MEL-MMIPs)。分别使用透射电镜(TEM)、热重分析(TGA)、傅立叶变换红外光谱(FT-IR)和振动样品磁强计(VSM)对制备的MMIPs进行表征。结果表明,印迹聚合物层成功地在Fe3O4@SiO2磁性材料表面包覆,印迹粒子具有良好的磁学性能。将磁性分子印迹聚合物应用于牛奶中三聚氰胺的富集分离,采用高效液相色谱法(HPLC)检测,结果显示该磁性表面分子印迹聚合物对三聚氰胺有特异性吸附。以制备的MMIPs为吸附剂,建立了一种简单、快速和高选择性测定牛奶中三聚氰胺的方法。 相似文献
14.
N. D. Chuvylkin A. M. Tokmachev A. V. Fionov E. V. Lunina 《Russian Chemical Bulletin》1997,46(10):1649-1662
The results of ESR-spectroscopic and quantum-chemical investigations of the coordination of 2,2,6,6-tetramethylpiperidineN-oxyl, 2,2,3,4,5,5-hexamethyl-3-imidazolidineN-oxyl, 2,2,4,5,5-pentamethyl-3-imidazolineN-oxyl, 2,4,5,5-tetramethyl-2-phenyl-3-imidazolineN-oxyl, and 2,4,5,5-tetramethyl-2-octyl-3-imidazolineN-oxyl to Lewis acid sites (LAS) on alumina surface are described systematically and analyzed. The cluster models of LAS accepted
in radiospectroscopy and based on experimental data on g-factors and hyperfine coupling constants with N and Al nuclei in
the corresponding donor-acceptor complexes are discussed. Within the framework of the unrestricted Hartree—Fock (UHF) method
using the STO-3G, STO-6G, 3–21G, and 6–31G basis sets and also in terms of semiempirical MNDO, AM1, and PM3 procedures, comparative
quantum-chemical analysis of the structural, spin, electrostatic, energy, and radiospectroscopic characteristics of the coordination
of the model cluster LAS to the simplest representative of nitroxides is performed. Three illustrative types of structures
of the resulting surface complex are considered. A semiquantitative interpretation of the whole set of features found experimentally
for the coordination of nitroxide probes to the surface LAS on alumina is given.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1743–1756, October, 1997. 相似文献
15.
Seong-Ho Choi Jae-Wan Seo Sang-Il Nam Mu-Sang Lee Kwang-Pill Lee 《Journal of inclusion phenomena and macrocyclic chemistry》2001,40(4):279-283
FT-Raman spectra of 2-, 3-, and 4-chlorostyrene included in-cyclodextrin (CD),glycerol ether -CD, -CD,sulfated -CD, andglycerol ether -CD were recorded.In the inclusion complexes, the area of the vinyl(C=C) band decreased remarkably, whereasthe area of the phenyl (C=C) band increasedcompared to those of liquid 2-, 3-, and 4-chlorostyrene,respectively. From the results, the inclusion structures of2-, 3-, and 4-chlorostyrene were discussed. 相似文献
16.
Dominik Huber P. G. Anil Kumar Paul S. Pregosin Igor S. Mikhel Antonio Mezzetti 《Helvetica chimica acta》2006,89(8):1696-1715
Chloride abstraction from the half‐sandwich complexes [RuCl2(η6‐p‐cymene)(P*‐κP)] ( 2a : P* = (Sa,R,R)‐ 1a = (1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐1‐phenylethyl)]phosphoramidite; 2b : P* = (Sa,R,R)‐ 1b = (1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐(1‐(1‐naphthalen‐1‐yl)ethyl]phosphoramidite) with (Et3O)[PF6] or Tl[PF6] gives the cationic, 18‐electron complexes dichloro(η6‐p‐cymene){(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐phenyl]ethyl}[(1R)‐1‐phenylethyl]phosphoramidite‐κP}ruthenium(II) hexafluorophosphate ( 3a ) and [Ru(S)]‐dichloro(η6‐p‐cymene){(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐naphthalen‐1‐yl]ethyl}[(1R)‐1‐(naphthalen‐1‐yl)ethyl]phosphoramidite‐κP)ruthenium(II) hexafluorophosphate ( 3b ), which feature the η2‐coordination of one aryl substituent of the phosphoramidite ligand, as indicated by 1H‐, 13C‐, and 31P‐NMR spectroscopy and confirmed by an X‐ray study of 3b . Additionally, the dissociation of p‐cymene from 2a and 3a gives dichloro{(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐(1‐(η6‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP)ruthenium(II) ( 4a ) and di‐μ‐chlorobis{(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐1‐(η6‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP}diruthenium(II) bis(hexafluorophosphate) ( 5a ), respectively, in which one phenyl group of the N‐substituents is η6‐coordinated to the Ru‐center. Complexes 3a and 3b catalyze the asymmetric cyclopropanation of α‐methylstyrene with ethyl diazoacetate with up to 86 and 87% ee for the cis‐ and the trans‐isomers, respectively. 相似文献
17.
Akiko Tsuchida Makoto Suda Masatoshi Ohta Takeshi Yamauchi Norio Tsubokawa 《Journal of polymer science. Part A, Polymer chemistry》2006,44(9):2972-2979
The effects of radicals on silica surface, which were formed by γ‐ray irradiation, on the polymerization of vinyl monomers were investigated. It was found that the polymerization of styrene was remarkably retarded in the presence of γ‐ray‐irradiated silica above 60 °C, at which thermal polymerization of styrene is readily initiated. During the polymerization, a part of polystyrene formed was grafted onto the silica surface but percentage of grafting was very small. On the other hand, no retardation of the polymerization of styrene was observed in the presence of γ‐ray‐irradiated silica below 50 °C; the polymerization tends to accelerate and polystyrene was grafted onto the silica surface. Poly(vinyl acetate) and poly(methyl methacrylate) (MMA) were also grafted onto the surface during the polymerization in the presence of γ‐ray‐irradiated silica. The grafting of polymers onto the silica surface was confirmed by thermal decomposition GC‐MS. It was considered that at lower temperature, the grafting based on the propagation of polystyrene from surface radical (“grafting from” mechanism) preferentially proceeded. On the contrary, at higher temperature, the coupling reaction of propagating polymer radicals with surface radicals (“grafting onto” mechanism) proceeded to give relatively higher molecular weight polymer‐grafted silica. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2972–2979, 2006 相似文献
18.
复合载体TiO2-Al2O3的制备及其对Ni-Mo-S负载型催化剂加氢脱氧性能的影响 总被引:1,自引:0,他引:1
采用共沉淀法制备出复合载体TiO2-Al2O3,用N2-吸附、XRD和吡啶吸附红外光谱等手段进行表征。采用原位硫化法制备Ni-Mo-S/TiO2-Al2O3负载型催化剂,以苯酚为模型化合物研究其加氢脱氧催化性能。主要研究铝源和沉淀剂对TiO2-Al2O3复合载体性能的影响以及其作为载体对Ni-Mo-S/TiO2-Al2O3催化苯酚加氢脱氧反应的影响。结果表明,以氯化铝为铝源制备的复合载体具有较大的孔容和孔径,孔容达1.12cm3/g,孔径达18.0nm;以硫酸铝为铝源和以碳酸氢铵为沉淀剂制备的复合载体具有较大的比表面积,高达295m2/g;氨水沉淀制备的复合载体具有较多的L酸;以硫酸铝为铝源制备的复合载体形成少量的B酸。TiO2-Al2O3作为载体影响Ni-Mo-S/TiO2-Al2O3负载型催化剂加氢脱氧性能的主要因素是载体的酸性和载体的比表面积。在300℃,4.0MPa条件下Ni-Mo-S/TiO2-Al2O3催化苯酚的转化率达81.9%,产物中无氧化合物的总选择性达100%,脱氧率达79.4%。 相似文献
19.
20.
Wenliu Zhuang Yong Zhang Qiong Hou Lei Wang Yong Cao 《Journal of polymer science. Part A, Polymer chemistry》2006,44(13):4174-4186
A series of soluble, conjugated, electrophosphorescent copolymers with (meso‐tetraphenylporphyrinato‐κ4N)platinum(II) (PtTPP) complexes incorporated into the polymer main chain were synthesized through the copolymerization of narrow‐band‐gap monomeric porphyrin–platinum(II) complexes and wide‐band‐gap dialkyl‐substituted fluorene monomers by a modified Suzuki coupling reaction. The study of the photoluminescence decay indicated that poly[2,7‐(9,9‐dioctylfluorene)‐co‐2,12‐((meso‐tetraphenylporphyrinato‐κ4N)platinum(II))] (PFO–PtTPP) was a triplet emitter. The electroluminescence emission from the fluorene segment was completely quenched for copolymers with PtTPP contents as low as 0.5 mol %. The PFO–PtTPP copolymers emitted deep red light. The device based on the porphyrin–platinum(II) copolymer PFO–5PtTPP (with 5 mol % PtTPP in the copolymer) showed the highest external quantum efficiency of 1.95% with an emission peak at 684 nm in an indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polyvinylcarbazole (PVK)/70:30 (w/w) PFO–5PtTPP: 2‐(biphenyl‐4‐yl)‐5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole/Ba/Al device configuration. In comparison with the PFO–PtTPP copolymers synthesized via a postpolymerization metalation route, copolymerization from Pt metal complexes proved to be a more efficient synthetic route for high‐efficiency electrophosphorescent polymers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4174–4186, 2006 相似文献