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1.
The synthesis, characteristics and analytical applications of biacetylmonoxime nicotinylhydrazone are described. This compound forms fluorescent complexes with titanium(IV) (λex = 430, λem = 540 nm), zirconium (λex = 415 nm, λem = 505 nm) and hafnium (λex = 400, λem = 500 nm) in an acidic medium. Titanium forms a 1:2 metal:ligand complex, whereas zirconium and hafnium form 1:2:1 metal:ligand:sulphate ternary complexes. Highly selective spectrofluorimetric methods for titanium (20–100 ng ml?1), zirconium and hafnium (5–100 ng ml?1) are proposed, and procedures for the analysis of binary mixtures of these ions are described.  相似文献   

2.
Four new coordination compounds, [Zn(dba)(bpy)]n (1), {[Zn(dba)(phen)]·2H2O}n (2), [Cd(dba)(bpy)(H2O)2] (3) and [Cd2(dba)2(phen)2]n (4) (H2dba = 2,5-dihydroxy-p-benzenediacetic acid, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline) have been prepared via solvothermal method and characterized by sin-gle-crystal X-ray diffraction, infrared spectroscopy, elemental analysis and powder X-ray diffraction. 1 and 2 possess 1D infinite chain structures. Complex 3 exhibits a mononuclear structure. Complex 4 owns bi...  相似文献   

3.
《Analytical letters》2012,45(12):1967-1973
Abstract

The reasons for fluorescence emitting from the mixture of colchicine and H2SO4 in different concentrations were investigated and confirmed through organic synthesis in this article. The compound N‐deacetylcolchiceine (1) which has native fluorescence at λexem=272/373 was obtained from the reaction of colchicine with diluted H2SO4. When colchicine reacted with concentrated H2SO4, another compound 2‐demethylcolchicine (2), which also has native fluorescence at λexem=294/358 was obtained.  相似文献   

4.
Using the principle of crystal engineering, four novel metal-organic coordination polymers, {[Cd1(nic)2(H2O)]2[Cd2(nic)2(H2O)2]}n (1), [Cd2(fma)2(phen)2]n (2), [Cd(fma)(bipy)(H2O)]n (3) and [Zn(mal)(bipy)·3H2O]n (4) (nic=nicotinate, fma=fumarate, mal=malate, phen=phenanthroline, bipy=2,2′-bipyridine) have been synthesized by hydrothermal reaction of M(CH3COO)2·2H2O (M=Zn, Cd) with nicotinic acid, fumaric acid and cooperative L (L=phen, bipy), respectively. X-ray analysis reveals that complex 1 possesses an unprecedented two-dimensional topology structure constructed from three-ply-like layers, complex 2 is an infinite 2D undulating network, complex 3 is a 1D zigzag chain and complex 4 belongs to a 1D chain. The results indicate a transformation of fumarate into malate during the course of hydrothermal treatment of complex 4. The photophysical properties have been investigated with luminescent excitation and emission spectra.  相似文献   

5.
Sodium salts of water‐soluble polymers poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(hexyloxy)‐1,4‐phenylene]} ( P1 ), poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(dodecyloxy)‐1,4‐phenylene]} ( P2 ), poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(dibenzyloxy)‐1,4‐phenylene]} ( P3 ), poly[2‐hexyloxy‐5‐(3‐sulfonatopropoxy)‐1,4‐phenylene] ( P4 ), and poly[2‐dodecyloxy‐5‐(3‐sulfonatopropoxy)‐1,4‐phenylene] ( P5 )] were synthesized with Suzuki coupling reactions and fully characterized. The first group of polymers ( P1 – P3 ) with symmetric structures gave lower absorption maxima [maximum absorption wavelength (λmax) = 296–305 nm] and emission maxima [maximum emission wavelength (λem) = 361–398 nm] than asymmetric polymers P4 (λmax = 329 nm, λem = 399 nm) and P5 (λmax = 335 nm, λem = 401 nm). The aggregation properties of polymers P1 – P5 in different solvent mixtures were investigated, and their influence on the optical properties was examined in detail. Dynamic light scattering studies of the aggregation behavior of polymer P1 in solvents indicated the presence of aggregated species of various sizes ranging from 80 to 800 nm. The presence of alkoxy groups and 3‐sulfonatopropoxy groups on adjacent phenylene rings along the polymer backbone of the first set hindered the optimization of nonpolar interactions. The alkyl chain crystallization on one side of the polymer chain and the polar interactions on the other side allowed the polymers ( P4 and P5 ) to form a lamellar structure in the polymer lattice. Significant quenching of the polymer fluorescence upon the addition of positively charged viologen derivatives or cytochrome‐C was also observed. The quenching effect on the polymer fluorescence confirmed that the newly synthesized polymers could be used in the fabrication of biological and chemical sensors. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3763–3777, 2006  相似文献   

6.
Two novel metal-organic frameworks, {[Eu(phen)(NDA)1.5(H2O)]}n ((1); NDA = 2,6-naphthalenedicarboxylate ions, phen = 1,10-phenanthroline) and {[Gd(phen)(NDA)1.5]·0.5H2NDA}n (2), have been synthesized under hydrothermal conditions. The structure analyses of 1 and 2 reveal that the two compounds belong to the triclinic system with space group P-1. Compound 1 features a 2D lattice structure while compound 2 displays a novel 3D architecture. The two frameworks were further characterized by elemental analyses, l...  相似文献   

7.
Five new coordination compounds, {[Mn(L)(CH3OH)2] · CH3OH · H2O} n (1), {[Cd(L)(DMF)2(H2O)] · H2O} n (2), {[Co(L)(CH3OH)4] · CH3OH}2 (3), {[Cd(L)(phen)(CH3OH)] · CH3OH} n (4), and {[Mn(L)(phen)(H2O)] · CH3OH} n (5) (L = 5-ferrocene-1,3-benzenedicarboxylic acid, phen = 1,10-phenanthroline) were obtained from different metal salts and L with or without 1,10-phen under mild conditions. Complex 1 is a 1-D ladder-like chain composed of 8-membered rings A and 16-membered rings B, which arrange alternately. Complex 2 is an infinite linear chain, further bridged to form a parallel double chain through different hydrogen-bond interactions. Complex 3 is a discrete dinuclear structure, while 4 is a neutral 1-D infinite zigzag coordination chain. Complex 5 is a 1-D linear chain with phen and ferrocene groups of L as pendants hanging on the different sides of the main chain. Variable temperature magnetic susceptibilities of 1 were measured and weak antiferromagnetic exchange interactions between the neighboring Mn(II) ions were found with J = ?0.95 cm?1.  相似文献   

8.
The coordination chemistry of 1,10-phenanthroline (phen) and sodium 1,3-benzothiazole-2-thiolate (SBT) with selected s-block elements has been investigated. Four metal complexes were prepared and their structures were characterized using a variety of analytical techniques including infrared, UV–visible, 1H NMR and 13C NMR spectroscopies, elemental analysis, mass spectrometry and single-crystal X-ray diffraction. The reactions of phen and SBT with M(X)n (M = K(I), Cs(I), Mg(II), Sr(II); X = OH, CO3, Cl; n = 1, 2) in MeOH–H2O yielded one-dimensional chains of both potassium [K2(phen)2(BT)2(H2O)4]n ( 1 ) and caesium [Cs(phen)(BS)(H2O)]n ( 2 ) (where BT = 1,3-benzthiazole-2-thiolate and BS = 1,3-benzthiazole-2-sulfinothiolate) and mononuclear complexes of both magnesium {[Mg(phen)(H2O)4](BT)2·phen} ( 3 ) and strontium {[Sr(phen)2(H2O)4](BT)2} ( 4 ). In these complexes, phen binds via an N,N′ chelate pocket, while the monoanonic BT ligands either coordinate in a bidentate fashion (in the case of 1 ) or remain uncoordinated (in the case of 3 and 4 ). In complex 2 , SBT ligand was oxidized in situ into a new BS ligand. The sulfinothiolate oxygen atoms in BS coordinate with caesium in a tridentate fashion. Complexes 1 – 4 were evaluated against urease for enzyme inhibition. The complexes displayed significant inhibition with IC50 values in the range 10.8–45.8 μM. In order to examine the structure–activity relationship, the complexes were docked at the active site of urease. Docking results clearly demonstrate the binding of each complex within the active site of the enzyme.  相似文献   

9.
Four novel mixed‐ligand complexes were obtained from the reaction of maleic acid, diimine chelating ligands and Cd(OH)2 or CdO in a mixed solvent of water and methanol. The complexes were characterized by IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction. The results show that all the four complexes are coordination polymers. [Cd(phen)(H2O)(male)]n · 2nH2O ( 1 ) and [Cd(bipy)(H2O)(male)]n · 2nH2O ( 2 ) (male = maleate; phen = 1, 10‐phenanthroline, bipy = 2, 2′‐bipyridine) are isomorphic, and the asymmetric unit is constructed by one CdII atom, a maleate group, a diimine ligand and two crystal water molecules. Each maleate group links two CdII atoms in a bis(bidentate) chelating mode, resulting in a 1D helical chain. Within [Cd(phen)(H2O)2(male)]n · 2nH2O ( 3 ), the maleate group bridges two CdII atoms in a bis(monodentate) chelating mode into a 1D helical chain along the [100] direction. The helical chain is decorated by phen groups alternatively at the two sides, and each phen plane of one chain is inserted in the void space between two adjacent phen ligands from an adjacent chain, resulting in a double zipper‐like chain. The asymmetric unit of [Cd2(phen)2(male)2]n ( 4 ) contains a CdII cation, one phen molecule, and a maleate group, and one bridging maleate group links three CdII atoms resulting in a 2D layer extending in [011] plane. The 2D networks are constructed by four kinds of rings formed by the central metal atom and maleate dianion. The thermostabilities of the four complexes were investigated.  相似文献   

10.
Two dinuclear complexes, {[Cd(bdpp)Cl2](CH3OH)}2 (1) and [Cd(bdpp)(N3)(NO3)]2 (2), have been synthesized by reactions of bdpp with cadmium salts (bdpp?=?1,3-bis(3′,5′-dimethylpyrazol-1′-yl)propane), and characterized by IR, element analysis, fluorescence properties and single crystal structural analysis. Cd in 1 has a trigonal bipyramidal coordination geometry and two such units form a dimer through two μ-Cl bridges. Each Cd in 2 has a distorted octahedral coordination geometry and two Cd units form a dimer through μ1,1-N3 bridges. The emission spectra show λem?=?413?nm for 1 and λem?=?338?nm for 2.  相似文献   

11.
The properties of 3-hydroxypyridine-2-aldehyde 2-pyridylhydrazone as a spectrophotometric and fluorimetric reagent are described. The four ionization constants are reported. A rapid procedure for the fluorimetric determination of 2—300 ppb(7.2 × 10-81.1 × 10-5 M) of aluminium in acetate-buffered medium is described (λex = 390 nm, λem = 475 nm). Interferences have been evaluated, and the procedure has been applied satisfactorily to the determination of aluminium in potable, fresh and sea waters.  相似文献   

12.
Three new one‐dimensional (1D) chain metal–nitroxide complexes {[Cu(NIT4Py)2(suc)(H2O)] · 3H2O}n ( 1 ), {[Cd(NIT4Py)2(suc)(H2O)] · [Cd(NIT4Py)2(suc)(H2O)2] · 3H2O}n ( 2 ), and {[Zn(NIT4Py)(glu)(H2O)] · H2O}n ( 3 ) [NIT4Py = 2‐(4′‐pyridyl)‐4, 4, 5, 5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide, suc = succinate anion and glu = glutarate anion] were synthesized and structurally characterized. Single‐crystal X‐ray analyses indicate that the three complexes crystallize in neutral 1D chains in which the metal‐nitroxide units are linked by flexible dicarboxylate anions. The succinate anions only adopt trans configuration in complexes 1 and 2 , whereas the glutarate anion has gauche/anti conformation in complex 3 . Magnetic measurements show that complex 1 exhibits weak antiferromagnetic interactions between the copper ions and the nitroxides.  相似文献   

13.
Two Cd(II) 1-D chain coordination polymers with Cd–Cl-Cd–Cl 1-D chains as bases, one connected to protonated 8-aminoquinoline by intermolecular hydrogen bonds {[Cd2(μ-Cl)4(Cl)2(CH3OH)(H2O)]·(H-aql)2} n (1) (aql = 8-aminoquinoline) and the other to 8-aminoquinoline [Cd(μ-Cl)2(aql)] n (2), have been synthesized and structurally characterized by single-crystal X-ray analysis. 1 belongs to the monoclinic system with space group P2(1)/m and 2 belongs to the monoclinic system with space group C2/c. Fluorescent properties of aql, 1, and 2 showed that the fluorescence spectrum (λmax = 386 nm) of 1 is mainly of aql ππ* character. The fluorescence spectrum of 2 which emits blue-green light (λmax = 497 nm) mainly involves a metal-perturbed intraligand ππ* transition from strong covalent bonds. Thermal stabilities of 1 and 2 have also been studied.  相似文献   

14.
Assembly reactions of orotic acid (H3dtpc ) and CdCl2·2.5H2O or CdSO4·8H2O yielded four new cadmium compounds {[Cd(H2dtpc)(phen)(H2O)2]·(H2dtpc)·4H2O}2 (1: solution reaction, pH=4-5, in addition of phen), [Cd3(dtpc)2(phen)5]·13H2O (2: hydrothermal reaction, initial pH=14, final pH=7.5), [Cd(Hdtpc)(H2O)3]4 (3: solution reaction, initial pH=6.5, final pH=6.0), {[Cd(Hdtpc)(phen)(H2O)]·H2O}n (4: hydrothermal reaction, initial pH=8; final pH=6.5), respectively. Compounds 1-4 have been characterized by IR, thermogravimetric analyses (TGA), photoluminescence analyses, single-crystal and powder X-ray diffraction (PXRD). Compound 1 is a binuclear, 2 is a trinuclear, 3 is a tetranuclear structure, and 4 possesses one-dimensional chain framework, respectively, in which the orotate ligands show seven different linking fashions in 1-4. The orotate ligands as trivalence anions are observed in the formation of orotate-compounds, in which the orotates show high stability under the extreme condition of strong basic solution, high temperature and pressure.  相似文献   

15.
Three zinc(II) benzenedicarboxylate coordination polymers, {ZnII(L1)(phen)(H2O)} n (1), {[ZnII(L2)(phen)]2} n (2), and {[ZnII(L3)(phen)(H2O)]} n (3) (L1?=?1,4-benzenedicarboxylic dianion, L2?=?1,3-benzenedicarboxylic dianion, L3?=?1,2-benzenedicarboxylic dianion, and phen?=?1,10-phenanthroline), have been synthesized by self-assembly. Structural analyses of 13 reveal that the compounds are one-dimensional (1-D) chains. However, the structural motifs for 13 are distinct from each other, where 1 forms 1-D zig-zag chains, 2 is in 1-D ladder-like motif, and 3 is a 1-D helical form. Compounds 13 exhibit photoluminescence with emission maxima at ca 371, 392, and 375?nm, respectively.  相似文献   

16.
Three new coordination polymers {[Cd(tza)(2,2′-bpy)(H2O)](ClO4)} n 1, {[Co(tza)(2,2′-bpy)(H2O)](ClO4)} n 2, and {[Cu(tza)(phen)](ClO4)} n 3 (Htza = tetrazole-1-acetic acid, 2,2′-bpy = 2,2′-bipyridyl, phen = 1,10-phenanthroline) were synthesized and characterized by X-ray single-crystal diffraction, elemental analysis, and IR spectra. Complexes 1 and 2 exhibit 3-D architectures formed by ππ interaction of 2,2′-bpy ligands interlinking to the adjacent 2-D layers. Complex 3 is a 1-D zigzag double chain and the 3-D structure is formed by ππ stacking interaction of phen and nonclassical hydrogen bonding.  相似文献   

17.
Five new divalent metal coordination polymers containing either 1,3‐adamantanedicarboxylate (adc) or 1,3‐adamantanediacetate (ada) and pillaring dipyridyl ligands were prepared and structurally characterized by single‐crystal X‐ray diffraction. Using the V‐shaped linker 4,4′‐dipyridylamine (dpa), three new phases were isolated. {[Zn2(ada)2(dpa)2] · 4.5H2O}n ( 1 ) shows a (4,4) grid topology with embedded octameric water clusters. {[Co(ada)(dpa)(H2O)] · H2O}n ( 2 ) also manifests a 2D dimensionality, but with an intriguing novel (4)(12)(4.125) looped topology. {[Cd(adc)(H2O)2] · H2O}n ( 3 ) did not incorporate dpa ligands during self‐assembly, but exhibits an uncommon 3‐connected 83 etb network topology. [Co(ada)(ebin)]n ( 4 ) [ebin = ethanediaminebis(nicotinamide)] possesses a (3,6) triangular net based on {Co2(OCO)2} dimeric units. {[Cd(adc)(ebin)] · 2H2O}n ( 5 ) also shows dimeric units, although linked into a decorated (4,4) grid topology. Magnetic susceptibility studies of compound 4 revealed a decrease in χmT product upon cooling, ascribed to antiferromagnetic coupling concomitant with single‐ion effects [g = 2.39(2) with D = 40(3) cm–1 and J = –3.55(4) cm–1]. Compounds 1 and 5 undergo blue‐violet fluorescence upon ultraviolet irradiation; the zinc derivative 1 shows potential as a sensor for the solution‐phase detection of nitrobenzene and m‐nitrophenol. Thermal decomposition behavior of the five new phases is also discussed.  相似文献   

18.
Three metal‐organic coordination polymers, namely {[Cd(L1)(1,2‐chdc)] · 2H2O}n ( 1 ), {[Ni(L2)(1,2‐chdc)] · H2O}n ( 2 ), and [Cd(L2)(npht)]n ( 3 ) [L1 = 1,2‐bis(2‐methylbenzimidazol‐1‐ylmethyl)benzene, L2 = 1,2‐bis(5,6‐dimethylbenzimidazol‐1‐ylmethyl)benzene, 1,2‐H2chdc = 1,2‐cyclohexanedicarboxylic acid, H2npht = 3‐nitrophthalic acid] were synthesized under hydrothermal conditions and structurally characterized by single‐crystal X‐ray diffraction methods, IR spectroscopy, TGA, and elemental analysis. In compound 1 , two 1,2‐chdc2– ligands connect two neighboring Cd atoms to form a dinuclear [Cd2(1,2‐chdc)2] subunit, which is further linked by L1 ligands to construct a 1D ladder‐like chain. Compound 2 exhibits a 2D (4,4) coordination network with {44.62} topology, whilst compound 3 shows a 1D helical chain structure. The fluorescence, UV/Vis diffuse reflection spectra, and catalytic properties of complexes 1 – 3 for the degradation of the congo red azo dye in a Fenton‐like process are investigated.  相似文献   

19.
Zinc and cadmium diphenate (dip, biphenyl‐2,2′‐dicarboxylate) coordination polymers containing conformationally flexible dipyridylamide ligands show diverse chain and layer topologies as determined by single‐crystal X‐ray diffraction. [Cd(dipH)2(bdin)]n ( 1 ) [bdin = N,N′‐(butane‐1,3‐diyl)diisonicotinamide] shows a simple 1D zigzag chain structure. {[Cd(dip)(pdin)(H2O)] · 1.25H2O}n ( 2 ) [pdin = N,N′‐(propane‐1,3‐diyl)diisonicotinamide] shows bilayer slabs formed by interleaving of (4,4) rectangular grid layers. {[Zn2(dip)2(3‐pna)2] · 3H2O}n ( 3 ) (3‐pna = 3‐pyridylnicotinamide) manifests a rare 4‐connected 1D ribbon topology. {[Cd(dip)(4‐ppbp)] · 2H2O}n ( 4 ) [4‐ppbp = propane‐1,3‐diylbis(piperidine‐4,1‐diyl)bis(pyridin‐4‐ylmethanone)] shows a 3,5‐connected layer with (426)(42678) 3,5L2 topology. {[Zn4(dip)4(H2O)2(4‐ppbp)2] · 12H2O}n ( 5 ) exhibits 2D 3,6‐connected layers with (43)2(466683) kgd topology featuring embedded R(8)A(2) classification 10‐membered water clusters. Compounds 1 , 4 , and 5 undergo violet or blue‐violet fluorescence upon ultraviolet irradiation. Thermal decomposition behavior of the new phases is also discussed.  相似文献   

20.
Self‐assembly of Cd(phen)2+ and Cu(phen)2+ (phen = 1,10‐phenanthroline) building blocks with the bent ligand 4,4′‐dithiodipyridine (dtdp) has been investigated. Both building blocks serve as corner units with constrained cis‐geometry. The arched chain coordination polymer [{Cd(phen)(μ‐dtdp)(dtdp)(H2O)}(ClO4)2·2CH3OH·1.5H2O]n ( 1 ) crystallised from a mixture of Cd(ClO4)2·H2O, phen and dtdp in methanol. The reaction of [Cu(phen)(H2O)2](CF3SO3)2 ( 2 ) with dtdp in an ethanol/water mixture yielded a chair‐like metallamacrocycle, [{Cu(phen)(CF3SO3)2}2(μ‐dtpd)2] ( 3 ). The crystal structure of the precursor complex 2 is also reported.  相似文献   

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