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1.
《Comptes Rendus Chimie》2017,20(3):209-220
Artificial photosynthesis is expected to include the development of light-harvesting antenna systems, similarly to what Natural Photosynthesis does. Here some basic requirements for designing synthetic light-harvesting antennae are presented, together with the results obtained by our team in the last few decades on light-harvesting antennae based on metal dendrimers or made of multibodipy species. 相似文献
2.
Saudan C Ceroni P Vicinelli V Maestri M Balzani V Gorka M Lee SK van Heyst J Vögtle F 《Dalton transactions (Cambridge, England : 2003)》2004,(10):1597-1600
We have investigated the complexation of lanthanide ions (Nd3+, Eu3+, Gd3+, Tb3+, Dy3+) with three cyclam-based ligands (cyclam = 1,4,8,11-tetraazacyclotetradecane), namely 1,4,8,11-tetrakis(naphthylmethyl)cyclam (1), and two dendrimers consisting of a cyclam core appended with four dimethoxybenzene and eight naphthyl units (2) and twelve dimethoxybenzene and sixteen naphthyl units (3). In the free ligands the fluorescence of the naphthyl units is strongly quenched by exciplex formation with the cyclam nitrogens. Complexation with the metal ions prevents exciplex formation and revives the intense naphthyl fluorescence. Fluorescence and NMR titration experiments have revealed the formation of complexes with different metal/ligand stoichiometries in the case of 1, 2 and 3. Surprisingly, the large dendrimer 3 gives rise to a stable [M(3)3]3+ species. Energy transfer from the lowest singlet and triplet excited states of the peripheral naphthyl units to the lower lying excited states of Nd3+, Eu3+, Tb3+, Dy3+ coordinated to the cyclam core does not take place. 相似文献
3.
Gianluca Ambrosi Mauro Formica Vieri Fusi Luca Giorgi Mauro Micheloni 《Coordination chemistry reviews》2008,252(10-11):1121
The coordination properties of a selected series of acyclic and macrocyclic ligands containing one or more phenolic groups are explored. The formation of polynuclear metal complexes was only considered highlighting the key role played by the phenoxide oxygen atom in binding two metal centres in a bridge disposition. This arrangement allows two metal ions to stay close each other and consequently these dinuclear centres are able to mimic many biological sites, especially those where the two metals can cooperate to form an active centre. Catalytic properties of these polynuclear complexes, when studied, have been reported. Also some of the numerous heterodinuclear metal complexes that have been synthesized are here reviewed, included several crystal structures. 相似文献
4.
《印度化学会志》2023,100(3):100931
Some new chemo-sensors (4,4'-((1E,1′E)-(2,2′-dichloro-[1,1′-biphenyl]-4,4′-diyl)bis(diazene-2,1-diyl))bis(3,5-dihydroxybenzoic acid), 4-((E)-(4-(N-(4-((E)-(4-carboxy-2,6-dihydroxyphenyl)diazenyl)phenyl)sulfamoyl)phenyl)diazenyl)-3,5-dihydroxybenzoic acid, 4-((E)-(4-((4-((E)-(4-carboxy-2,6-dihydroxyphenyl)diazenyl)-2-sulfophenyl)amino)phenyl)diazenyl)-3,5-dihydroxybenzoic acid) were synthesized. These synthesized sensors were then characterized by FTIR, TLC, UV–Visible spectrophotometry, and NMR techniques. The sensors showed the best results for detection of all type of heavy metal ions simply by changing the colour of metal ion solution and by shifting in the λmax values of sensors due to interactions. 相似文献
5.
Summary Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of 4-amino-5-mercapto-3-trifluoromethyl-s-triazole (AMTT) and 5-mercapto-4-salicylideneamino-3-trifluoromethyl-s-triazole (MSTT) have been synthesized and characterized on the basis of elemental analyses, magnetic measurements, infrared and electronic spectral data. The ligandsAMTT andMSTT were characterized by elemental analyses, infrared and1H NMR spectral studies.AMTT, involving N and S as donor atoms, andMSTT, involving N, O and S as donor atoms, act as bi- and tridentate ligands, respectively. The geometry of the complexes has been assigned on the basis of magnetic and electronic spectral data. EPR parameters for copper (II) complexes have been calculated. Thermal stabilities of the complexes are also reported. Due to insolubility in water and common organic solvents and infusibility at higher temperatures, all the complexes are thought to be polymeric in nature.
Triazole als Komplexierungs-Agentien: Synthese und Strukturuntersuchungen an einigen bivalenten Metallionenkomplexen mit zwei- und dreizähnigen Liganden
Zusammenfassung Es wurden Co(II)-, Ni(II)-, Cu(II)-, Zn(II)- und Cd(II)-Komplexe von 4-Amino-5-mercapto-3-trifluormethyl-s-triazol (AMTT) und 5-Mercapto-4-salizylidenamino-3-trifluormethyl-s-triazol (MSTT) hergestellt und mittels Elementaranalyse, magnetischen Messungen, Infrarot- und Elektronenspektroskopie charakterisiert. Die LigandenAMTT undMSTT wurden elementaranalytisch und spektroskopisch (IR und1H-NMR) charakterisiert.AMT wirkt über die N-und S-Donoratome als zweizähniger Ligand,MSTT über N, O und S als dreizähniger Ligand. Die Geometrie der Komplexe wurde auf der Basis von magnetischen und elektronenspektroskopischen Daten zugeordnet. Für die Cu(II)-Komplexe wurden die EPR-Parameter berechnet. Die thermischen Stabilitäten der Komplexe wurde ebenfalls untersucht. Wegen ihrer Unlöslichkeit in Wasser und gängigen organischen Lösungsmitteln und der Unschmelzbarkeit bei höheren Temperaturen wird eine polymere Natur der Komplexe angenommen.相似文献
6.
Jean-Luc Fillaut Julien Andriès Pierre-Henri Lanoë Loic Toupet 《Journal of organometallic chemistry》2008,693(2):228-234
Flavonol based alkynyl ruthenium complexes devoted to the detection of metal traces in solution are described. The sensitivity of both absorption and emission properties of the 3-hydroxyflavone unit as a receptor for the metal cations, and of an alkynyl ruthenium moiety as an extended π-conjugated system, provides an efficient molecular sensor for rapid, sensitive and selective detection of lead(II) cations. 相似文献
7.
《Journal of Coordination Chemistry》2012,65(1):18-27
Four new complexes, [M(C9H5N2O3)2(H2O)2]·CH3OH (M?=?Zn(II), Cd(II) and Mn(II)) (1–3) and [Cu(C9H5N2O3)2] (4), have been synthesized by reactions of 5-nitro-quinoline-8-yl acetate (NQA) and corresponding metal salts at room temperature and characterized by elemental analysis, IR, thermal gravimetric analysis (TGA), fluorescence measurement and single crystal X-ray diffraction. 1–3 are mononuclear, further extended to 2-D layers by hydrogen bonds. For 4, Cu2+ is coordinated by two N atoms and two O atoms from two NQ ligands. TGA indicates that 1–4 have good thermal stabilities. Furthermore, 1 and 2 show excellent luminescence in the solid state at room temperature. 相似文献
8.
Bernd M. Rode 《Theoretical chemistry accounts》1980,56(3):245-251
The influence of metal ions on hydrogen bonds formed by their ligands to other molecules is studied at the example of the water dimer and lithium ion by means of ab initio calculations using a 8s/4p + P Gaussian basis set. Potential curves for the dimer separation and proton transfer are reported, and the results are used to discuss the ion influence on structure, rotation and the first part of the autoprotolysis reaction of the dimer. Several properties of electrolyte solutions can be related to the principal effects predicted by our calculations. 相似文献
9.
Metal–organic frameworks(MOFs) are a fascinating class of crystalline materials constructed from selfassembly of metal cations/clusters and organic ligands. Both metal and organic components can be used to generate luminescence, and can further interact via antenna effect to increase the quantum yield,providing a versatile platform for chemical sensing based on luminescence emission. Moreover, MOFs can be miniaturized to nanometer scale to form nano-MOF(NMOF) materials, which exhibit many advantages over conventional bulk MOFs in terms of the facile tailorability of compositions, sizes and morphologies, the high dispersity in a wide variety of medium, and the intrinsic biocompatibility. This review will detail the development of NMOF materials as chemical sensors, including the synthetic methodologies for designing NMOF sensory materials, their luminescent properties and potential sensing applications. 相似文献
10.
Yao‐Min Hu Jing Qu Yong‐Ling Yi Cong‐Cong Hu Hong‐Ling Gao Jian‐Zhong Cui 《无机化学与普通化学杂志》2013,639(1):115-120
Two complexes, Zn4(C9H5N2O3)8(4, 4′‐bipy)2 ( 1 ) and [Cd(C9H5N2O3)2(2, 2′‐bipy)] · 2H2O ( 2 ) were synthesized by solvothermal reactions of transition metal nitrates with 5‐nitro‐quinoline‐8‐yl acetate (NQA) under intervention of auxiliary ligands, and characterized by elemental analysis, IR spectroscopy, TGA, and single‐crystal X‐ray diffraction. In complex 1 , every 4, 4′‐bipy adopts a monodentate bridging mode and links two dinuclear asymmetric units, resulting a centrosymmetric neutral tetranuclear zinc complex. Complex 2 is a mononuclear complex, which is alternately arranged to form a 2D network through four kinds of hydrogen bonds. Furthermore, complexes 1 and 2 show excellent luminescent properties in solid state at room temperature. 相似文献
11.
The S-methylation of a macrocyclic tetrathiolactam afforded a new macrocyclic thioimidate that exhibited good affinity toward metal ions. The molecular structures of the macrocyclic ligand and its metal complexes were determined by X-ray crystallography. 相似文献
12.
Yi Cui Qi Chen Dan‐Dan Zhang Jie Cao Bao‐Hang Han 《Journal of polymer science. Part A, Polymer chemistry》2010,48(6):1310-1316
Two well‐defined triphenylamine‐based fluorescent conjugated copolymers with pendant terpyridyl ligands were synthesized through Suzuki coupling polymerization and were further characterized by 1H‐NMR, 13C‐NMR, gel permeation chromatography, Infrared, and UV‐vis spectra. Polymer P‐1 , terpyridine‐bearing poly(triphenylamine‐alt‐fluorene) with a high fluorescence quantum yield (62%) shows much higher sensitivities toward Fe3+, Ni2+, and Cu2+ as compared with the other metal ions investigated. Especially, Fe3+ can lead to an almost complete fluorescence quenching of polymer P‐1 . Whereas, the analogous polymer P‐2 , in which N‐ethylcarbazole repeat units replace the fluorene units in P‐1 , shows a very poor selectivity. It demonstrates that polymers with a same receptor may show different sensitivity to analytes owing to their different type of backbones. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1310–1316, 2010 相似文献
13.
Paul R. Haddad Miroslav Macka Emily F. Hilder Declan P. Bogan 《Journal of chromatography. A》1997,780(1-2):329-341
The use of micellar electrokinetic capillary chromatography (MEKC) for the separation of metal ions and metal-containing species is reviewed, together with the use of metal ions as a means to separate other species. Topics covered include the manipulation of separation selectivity through the use of complexation reactions induced by addition of a metal ion to the background electrolyte, enantiomeric separations facilitated through metal-analyte interactions, separation of organometallic species, separation of stable metal complexes in which the entire complex is the analyte and the separation of metal ions as analytes using pre-capillary or on-capillary complexation reactions with a suitable ligand. 相似文献
14.
The combination of transition metals and ligands featuring photochromic units is receiving much attention and opens up new perspectives for the design of metal-based photoswitchable molecules. This account summarizes some of our recent works made in the area of photochromic organometallic and coordination compounds, which have been used for the photomodulation of the quadratic non-linear optical (NLO) properties, as well as of the photoregulation of the emission properties of the resulting systems. For this purpose, we have designed new chromophores combining dithienylethene (DTE)-based bipyridine ligands with different metallic fragments (ReI, FeII, RuII, IrIII, CuI, ZnII), giving rise to multi-photochromic metal complexes containing from two to six DTE units, and studied the photocontrol of both NLO and luminescence properties. 相似文献
15.
Michinori Akaiwa Hiroki Fukumoto Takakazu Yamamoto 《Journal of organometallic chemistry》2005,690(18):4192-4196
Thioamide-based tridentate ligands, 1,3-benzenedicarbothioamides (1a-c), were used to afford pincer palladium(II) complexes (Pd(1-H)Cl, 2a-c) with η3-S,C,S type coordination. The complexes exhibit strong emission in a glassy frozen state as well as in the solid state. The decay lifetime of the emission from the complexes is in a range of 8-9 × 10−5 s, which is indicative of phosphorescent emission. 相似文献
16.
The synthesis of two new green fluorescent poly(propyleneimine) dendrimers from first generation has been described. The new materials are comprised of a 1,8-naphthalimide fluorophore having a substituent at C-4 position. The substituent in the first case is a N,N-dimethylaminoethylamino group while in the second one it is N-methylpiperazine. The spectroscopic and photophysical characteristics of the new dendrimers determined in organic solvent of different polarity have been presented. Both dendrimers show substantial increases in their fluorescence intensity in the presence of metal cations (Zn2+, Co2+, Ni2+, Pb2+, Mn2+, Cu2+, Fe3+ and Ag+) and protons. The influence of the photoinduced electron transfer on their sensing properties has been discussed. 相似文献
17.
A review is given on optical means for single shot testing (probing) as well as continuous monitoring (sensing) of heavy metal ions (HMs). Following an introduction into indicator based approaches, we discuss the types of indicator dyes and polymeric supports used, as well as existing sensing schemes for HMs. The wealth of information is compiled in the form of tables and critically reviewed. Notwithstanding the tremendous work performed so far, it is obvious that still severe limitations do exist in terms of selectivity, limits of detection, dynamic ranges, applicability to specific problems, and reversibility. On the other hand, such sensors have found — and will find — their application whenever rapid and cost-effective testing is required, where personnel is scarce or unskilled, and in field tests. Despite their limitations, the number of such sensors (and of irreversible probes) for HMs is likely to increase in future. 相似文献
18.
Geert Dehaen Gregory Absillis Kris Driesen Koen Binnemans Tatjana N. Parac‐Vogt 《Helvetica chimica acta》2009,92(11):2387-2397
Luminescence spectra of aqueous solutions containing a fixed concentration of tetracycline (TC) and increasing concentrations of Eu3+ were recorded both in the absence and presence of hydrogen peroxide (H2O2). In H2O2‐free solutions in which the Eu/TC molar ratio was varied from 1 : 1 to 8 : 1, the 5D0→7F0 transition consisted of only one peak at 580 nm. In the presence of H2O2, an extra peak appeared in the spectrum at 578 nm when the Eu/TC molar ratios were above 2.5. A detailed analysis of this spectral region revealed that at lower Eu/TC molar ratios (up to 2 : 1), the 5D0→7F0 transition experienced a slight blue shift. This indicates that at low Eu/TC molar ratios, the presence of H2O2 leads to two different environments of the trivalent europium ions, which most likely form bridged peroxide complexes with hydrogen peroxide (μ‐H2O2 ligand). Luminescence spectra measured in the presence of molybdate ions, which catalytically decompose H2O2, led to the disappearance of the extra europium(III) site that was formed in the presence of H2O2. The intensity of the hypersensitive 5D0→7F2 transition did not linearly depend on the H2O2/TC molar ratio. For H2O2/TC ratios up to 10, a sharp linear increase of the peak intensity was observed, but with further increase of the H2O2 concentration, the intensity remained nearly constant. For H2O2/TC ratios above 100, the intensity of this transition even started to decrease, which limits the use of the (tetracycline)europium(III) system to quantify hydrogen peroxide in solution. 相似文献
19.
One 6-metal Zn-Nd complex[Zn2Nd4L2(OAc)10(OH)2(CH3OH)2](1)with Schiff base ligand bis(3-methoxysalicylidene)ethylene-1,2-phenylenediamine(H2L)was constructed,and it has nanoscale rectangular structure(8×11×28 A).Excited by ligand-centered absorption bands,1 shows NIRemission of Nd3+ion.Interestingly,1 exhibits lanthanide luminescent response towards metal ions,especially to alkali metal ions(Li+,Na+ and K+)at ppm level. 相似文献
20.
Activation of CdS nanoparticles by metallic ions and their selective interactions with PAMAM dendrimers 总被引:3,自引:0,他引:3
CdS nanoparticles (NPs) in colloidal dispersion were activated by metallic ions [Mn(II) and Cu(II)], employing a simple method under mild conditions. These metallic ions on the surface of the CdS NPs quench the red-shifted defect emission, and efficiently promote near band gap emission; they also enhance the photo stability and dispersability of the suspensions. Taking advantage of the chemical affinity of Mn(II) and Cu(II) for the CdS surface, we carried out a study of the interaction between [CdS-M(II)
n
] NPs and polyamidoamine dendrimers of 1 and 2.5 generations (G1=8 amino, and G2.5=32 carboxylic end-groups, respectively). The strong interaction between these two chemical species results in the formation of new [CdS-M(II)
n
G
n
] nanocomposites. All colloidal systems were monitored by UV-visible electronic absorption and emission spectroscopies, and electronic paramagnetic resonance. The crystal structures of the nanocomposites, as well as their average diameters (2.0–3.3 nm), were determined by high-resolution transmission electron microscopy images. 相似文献