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1.
ESR and IR measurements have been carried out for a copper(Ⅱ)complex ofphenolic polymeric crown ether,As a result,the triplet ESR spectrum(S=1)of 3d_z2ground state copper(Ⅱ)ions was first observed for the powder sample.It indicatedthat there existed intramolecular spin-spin interaction betweeen 3d_Z2 groundstate copper(Ⅱ)and copper(Ⅱ)ions.In this binuclear triplet cluster,the axialligntion of one water molecule in a sandwich position to two adjacent copper(Ⅱ)ions was also confirmed by IR spectra,All things considered,a possible structurefor the complex was proposed.  相似文献   

2.
Complexes formed from lanthanide thiocyanates (except Pm, Tm and Lu) and 1,8-naphtho-16-crown-5 have been synthesized and characterized by elemental analyses, IR spectra, TG-DTA and electrical conductivity measurements. A single crystal structural analysis for the complex of Er(NCS)_3 with 1,8-naphtho-16-crown-5 has been performed. The result shows that Er(Ⅲ) ion is coordinated simultaneously by five oxygen atoms of the crown ether and three nitrogen atoms of thiocyanates. The coordination number of Er(Ⅲ) ion is eight.  相似文献   

3.
A new copper(Ⅱ) complex of CuLCl_2, where L = N~1-(1-pyrazin-2-yl-ethylidene)-ethane-1,2-diamine, a tridentate Schiff base derived from 2-acetylpyrazine has been prepared. The complex has been characterized by FT-IR, elemental analysis and single-crystal X-ray diffraction studies. Structural studies reveal that CuLCl_2 is a mononuclear copper(Ⅱ) complex with distorted square pyramidal geometry. Antifungal activity of CuLCl_2 was investigated by use of microcalorimetric measurement system and evaluated against S. pombe. It has high antifungal activity with IC_(50) = 213 μg/mL.  相似文献   

4.
Metalloporphyrins and crown ether groups were simultaneously supported on chloromethylated polystyrene resin to produce a series of polymer-supported catalysts. The synthesis of these catalysts has been studied. The influence of pH, concentrations of NaOCl and phase transfer catalysts on the epoxidation of styrene catalyzed by these catalysts has also been investigated. The experimental results show that manganese(Ⅲ) porphyrin bound to chloromethylated polystyrene which bears crown ether groups is effective catalysts for the epoxidation of styrene by sodium hypochlorite. The introduction of crown ether groups increases the catalytic efficiency of supported metalloporphyrins. The kinetics of epoxidation catalyzed by supported manganese(Ⅲ) porphyrins obeys Michaelis-Menten equation-the characteristic of enzyme-driven reaction.  相似文献   

5.
A novel zinc phthalocyanine containing four 17-crown-5 ether voids(17C5ZnPc) has been synthesized and characterized. UV-visible absorption and fluorescence emission spectra and as-sociated photophysical parameters have been determined. In contrast to most of the crown ether substituted phthalocyanines, no cofacial dimer formation is observed in the presence of alkali metal salts. In addition to the fluorescence at 710 nm from S1, a strong upper excited state (Soret 52) emission around 424 nm has been detected for the first time in the phthalocyanine series. Fluorescence decay of S1 and S2 emission can be analyzed by mono- and biexponential fits respectively. X-ray structure analysis showed that the crown ether unit is conformationally deformed and oblate that may account for the unusual spectroscopic properties.  相似文献   

6.
A novel chiral copper(Ⅱ) complex with racemic 1,2-diaminocyclohexane and iodide,[Cu(Ⅱ)(1,2-diaminocyclohexane)_3](I)_2·3H_2O(1) has been synthesized and structurally characterized by X-ray single-crystal diffraction,elemental analysis,infrared spectroscopy,Raman spectroscopy and thermogravimetric analysis. In complex 1,the CuⅡ ion was coordinated by six nitrogen atoms of three 1,2-diaminocyclohexane molecules. The structure of complex 1 can be described as a supramolecular 3D-like structure which was formed by intermolecular hydrogen-bonding interactions between mononuclear molecules,uncoordinated water molecules and two iodide anions. UV-vis absorption spectrum and surface photovoltage properties of complex 1 have also been studied.  相似文献   

7.
The computations of the electronic structures and properties of a novel crowned [60] fulleropyrrolidine (CFP) were performed by means of AM1 methods. It has been indicated that CFP has four isomers in which the dihedral angle between phenyl group and pyrrolidine ring is around ±90°. The study of electronic structures showed that the energy levels of frontier orbitals are determined mainly by C_(60). C_(60) acted as an electronic acceptor, whereas crown ether acted as an electronic donor, which implies that there exists intramolecular charge transfer effect in this molecule. The study of nonlinear optical properties implied that the hyperpolarizability of CFP can match that of p-nitroaniline. In the meantime, the hyperpolarizability properties of CFP could be influenced by the orientation of crown ether moiety.  相似文献   

8.
QIN Bei 《结构化学》2012,31(8):1187-1193
A new asymmetric bidentate copper(Ⅱ) complex,CuL 2(HL=2-((E)-(4-bromophenylimino)methyl)-6-bromo-4-chlorophenol),has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction.The complex crystallizes in the monoclinic space group P2 1 /c with a=11.218(3),b=9.355(3),c=13.449(4),β=108.722(4)°,V=1336.8(6)3,Z=2,Dc=2.008 g/cm 3,μ(MoKα)=7.024 mm-1,F(000)=806,S=0.999,the final R=0.0342 and wR=0.0641for2611observed reflections (I>2σ(I)).The central copper(Ⅱ) is four-coordinate and bonds to two nitrogen and two oxygen atoms from two Schiff base ligands.The complex is linked into a two-dimensional supramolecular structure by weak intermolecular interactions.In addition,DNA-binding properties of the metal complex were investigated using spectrometric titrations and viscosity measurements.The results show that the complex binds with calf-thymus DNA(CT-DNA),presumably via a partial intercalative mode.The intrinsic binding constant of the Cu(Ⅱ) complex with DNA is 7.335×10 3 M-1.  相似文献   

9.
A three-dimensional framework copper(Ⅱ) coordination polymer with copper carbonate basic and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) has been hydrothemally synthesized.The complex (2,C14 H10 CuN8 ·3H2 O) crystallizes in tetragonal,space group P4 2 /n,a=2.08581(12),b=2.08581(12),c=0.72331(4) nm,M r=761.73,V=3.1468(3) nm 3,Dc=1.608 g/cm 3,Z=4,F(000)=1552,GOOF=1.07,R=0.0515 and wR=0.1689.Every asymmetric unit molecular structure of the complex is composed with one copper ion,one and half water molecules and two Hpt molecules.Each copper ion is coordinated with five nitrogen atoms from four Hpt molecules,forming a distorted square pyramidal geometry.The fluorescence spectrum analysis shows that the title complex at room temperature exhibits intense photoluminescence with maximum emission at 450 nm.The quantum chemistry calculation study on the complex has been performed.The stability,some frontier molecular orbital energies and composition characteristics of some frontier molecular orbitals of the complex have been investigated.  相似文献   

10.
The structure of the title compound has been determined by X-ray crystallography. Each copper atom is chelated by two N-salicylidene-aniline anion ligands with Cu-O and Cu-N distances of 0.187 6(3) and 0.200 1(4) nm, respectively. The central copper(Ⅱ) is four-coordinated and in distorted square-planar environment. The phenyl rings with salicylidene moieties form a dihedral angle of 65.40°. There are C-H…π supramolecular interactions in the crystal structure. The title compound is also examined by elemental analysis, FT-IR, UV spectra and TG-DSC analysis. CCDC: 222315.  相似文献   

11.
A lariat crown ether compound 7,16-bis(2-hydroxy-5-methylbenzyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane has been prepared via one-pot Mannich reaction. A copper(II) complex with the ligand 7,16-bis(2-hydroxy-5-methyl-3-nitrobenzyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane was unexpectedly synthesized and characterized by elemental analysis, IR and UV spectra. The crystal structure of the complex has been determined by X-ray diffraction. Both crystal structure analysis and spectroscopy study indicated that the side-arm phenols of lariat crown ether are nitrated while complexing with Cu(NO3)2. Structure shows that the copper(II) ion is coordinated to two nitrogen and four oxygen atoms, two from the crown ether and other two from the deprotonated phenolate groups. The coordination polyhedron is a distorted octahedron.  相似文献   

12.
《Polyhedron》2003,22(25-26):3249-3253
Reaction of the crown ether ligand H2L (H2L=7,16-bis (5-t-butyl-2-hydroxybenzyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane) with Cu(Ac)2 and Cu(NO3)2 affords complexes 1 and 2, respectively, which are characterized by elemental analysis, IR and UV–Visible spectroscopy and X-ray diffraction. Both crystal structure analysis and spectroscopy study unexpectedly showed that the two side-arm p-tert-butylphenols of the original crown ether are converted to nitro p-tert-butylphenols in complex 2. In each complex the copper (II) ion is coordinated to two nitrogen and four oxygen atoms, two from the crown ether ring and other two from the deprotonated phenolate groups, which define an elongated octahedron. Electrochemical studies indicate that the two complexes undergo irreversible reduction in DMF solution.  相似文献   

13.
The reaction of tetraaza[14]annulene and its complexes with nicotinoyl chloride hydrochloride and/or isonicotinoyl chloride hydrochloride produced the 7,16-dinicotinoylated and/or 7,16-diisonicotinoylated corresponding products in satisfactory yields. The mass spectra reveal the molecular ion peaks due to the 7,16-diacylated products. A strong ir band which is correlated with a C = 0 stretching mode is freshly observed in the 1635–1670 cm?1 region upon the acylation. The electronic spectra for the complexes hardly change upon the acylation, but those for the ligands change slightly. The olefinic proton signals at the 7- and 16-positions disappear on the acylation in 1H-nmr spectra and the substituted pyridine proton signals are newly observed. The proton nmr results are consistent with those of the carbon-13 nmr. The spin Hamiltonian parameters for the acylated copper(II) complexes are comparable with those for the copper(II) complex which is not acylated. The copper(II) complexes assume the square-planar coordinations with an unpaired electron in the dx2?y2 orbital.  相似文献   

14.
A novel macrocycle, 5,14-dihydro-7,16-diethyldipyrazo[b,i][1,4,8,11]tetraazacyclotetradecine, has been synthesized from 1,2-diaminopyrazine and 2-ethyl-3-ethoxyacrolein. The absorption bands appearing in the energy range greater than 20000 cm?1 were attributable to the π → π transitions. The bands in the range of the 20100–23300 cm?1 show more bathochromic shift and greater intensity than those observed for corresponding 5,14-dihydro-7,16-diethyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine and/or 5,14-dihydro-7,16-diethyl-(Z)-dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine. The nickel(II), copper(II) and palladium(II) complexes of 5,14-dihydro-7,16-diethyldipyrazo[b,i][1,4,8,11]tetraazacyclotetradecine have been synthesized using a metal template reaction. In 1H and 13C nmr spectra, the signals of annulene skeleton for metal-free ligand and its complexes were found to observe in the lower field than those of the dibenzoanalogue.  相似文献   

15.
A new PVC membrane electrode for the triiodide ion based on a charge-transfer complex of iodine with 7,16-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane as a membrane carrier was prepared. The electrode exhibits a Nernstian response for triiodide ions over a wide concentration range (1.0 x 10(-1)-1.0 x 10(-5) M) with a slope of 59.3 +/- 0.9 mV decade(-1) and a detection limit of 6.3 x 10(-6) M. It has a response time of 30 s and can be used for at least 3 months without any divergence in the potential. The potentiometric response is independent of the pH, in the pH range 1.6 - 10.0. The proposed electrode has shown very high selectivity for the triiodide ion over a wide variety of other anions. This electrode was successfully applied as an indicator electrode in the potentiometric titration of ascorbic acid and hydroquinone from pharmaceutical preparations as well as ascorbic acid in orange juice and dissolved O2 in tap water.  相似文献   

16.
Reaction of N,N'-bis(phosphonomethyl)-1,10-diaza-18-crown-6 (H(4)L) with copper(II) acetate in 1:1 ethanol/water mixed solvents afforded a new crystal-engineered supramolecular metal phosphonate, Cu(H(2)L) (complex 1). By reaction of the same ligand with cadmium(II) nitrate in a 2:1 (M/L) ratio in methanol, a cadmium(II) complex with a 3D network structure was isolated, Cd(2.75)(L)(H(2)O)(7) x 1.5NO(3) x 7H(2)O x MeOH (complex 2). The copper(II) complex crystallized in the monoclinic space group P2(1)/c, with a =10.125(4), b = 14.103(6), and c = 14.537(6) A, beta = 91.049(8) degrees, V = 2075.4(16) A(3), and Z = 2. The Cu(II) ions in complex 1 are 6-coordinated by two phosphonate oxygen atoms, two nitrogen, and two oxygen atoms from the crown ether ring. Their coordination geometry can be described as Jahn-Teller-distorted octahedral, with elongated Cu-O(crown) distances (2.634(4) and 2.671(4) A for Cu(1) and Cu(2), respectively). The other two crown oxygen atoms remain uncoordinated. Neighboring two Cu(H(2)L) units are further interlinked via a pair of strong hydrogen bonds between uncoordinated phosphonate oxygen atoms, resulting in a one-dimensional supramolecular array along the a axis. The cadmium(II) complex is tetragonal, P4(2)/n (No. 86) with a = 20.8150(9) and c = 18.5846(12) A, V = 8052.0(7) A(3), and Z = 8. Among four cadmium(II) atoms in an asymmetric unit, one is 8-coordinated by four chelating phosphonate groups, the second one is 8-coordinated by 6 coordination atoms from a crown ring and two oxygen atoms from two phosphonate groups, the third Cd(II) atom is octahedrally coordinated by three aqua ligands and three phosphonate oxygen atoms from three phosphonate groups, and the fourth one is 6-coordinated by four aqua ligands and two oxygen atoms from two phosphonate groups in a distorted octahedral geometry. These cadmium atoms are interconnected by bridging phosphonate tetrahedra in such a way as to form large channels along the c direction, in which the lattice water molecules, methanol solvent, and nitrate anions reside. The effect of extent of deprotonation of phosphonic acids on the type of complex formed is also discussed.  相似文献   

17.
A new method of synthesis of the lariat crown ether 1,4,10,13-tetraoxa-7,16-diaza(diphenylmethyl)cyclooctadecane (L) has been described. The sodium thiocyanate complex with L [NaL](NCS) has been studied by X-ray crystallography, and the major vibrational frequencies in its IR spectrum have been assigned. The crystals of the complex are monoclinic: a = 11.538(2) Å, b = 9.796(2) Å, c = 7.564(2), Å, β = 90.38(3)°, Z = 2, space group P21/c, R1 = 0.0486 for 1733 reflections with I > 2σ(I). The compound has an ionic structure. In the centrosymmetric cation [NaL]+, both the macrocyclic part and the side groups of the ligand L are involved in coordination with the metal atom. The coordination polyhedron of the Na atom is a hexagonal bipyramid in which the equatorial plane is formed by six donor atoms of the substituted diaza-18-crown-6 ether (DA18C6) (av. Na-Oether, 2.682 Å; Na-N, 2.861 Å). The phosphoryl oxygen atoms of the side chains of the ligand occupy the axial positions (Na-OP, 2.325 Å). It is demonstrated that the cationic complexes of L can be, in principle, used as components of supramolecular machines.  相似文献   

18.
This paper describes the design, synthesis, and the characterization of the two new chromogenic crown ethers 2,2′-[1,4,10,13-tetraoxa-7,16-diazacyclooctadecane-7,16-diylbis(methylene)]bis[4-[(1-methyl-4-(1H)-pyridinylidene)ethylidene]-2,5-cyclohexadien-1-one (KBC-001) and the lipophilic derivative 2,2′-[1,4,10,13-tetraoxa-7,16-diazacyclooctadecane-7,16-diylbis(methylene)]bis[4-[(1-dodecyl-4-(1H)-pyridinylidene)ethylidene]-2,5-cyclohexadien-1-one (KBC-002). A merocyanine dye that forms a betainic structure upon intramolecular charge transfer and shows solvent polarity dependent spectral sensitivity was selected as the chromophore system to develop the new chromoionophores. This approach allows the design of overall electrically neutral ligands bearing charged groups without the need of external counter ions. A proton ionizable group in the dye moiety acts as a charged ion-binding site and is an integral part of a lariat crown ether ionophore. A chromoionophore for calcium ion sensing has been developed, which combines the size-selective binding character of a crown ether with strong electrostatic attraction between the positively charged calcium ion and two negatively charged lariat side arms in the overall neutral compound. This water-soluble dye selectively responds to the presence of calcium ions in water at pH 8.5 with a dynamic response range between 10 μM and 10 mM. The binding event can be monitored both by absorption spectrometry and by fluorescence spectrometry. No cross-sensitivity was found for the physiologically important cations Mg2+, Li+, Na+, and K+ up to concentrations of 0.1 M under the same experimental conditions. In contrast to the water-soluble reagent KBC-001, the lipophilized derivative KBC-002 having two long alkyl chains was successfully applied to ion-exchange type optode membranes made from plasticized poly(vinyl chloride) (PVC). The dynamic response range of the optode at pH 9.0 was between 10 μM and 10 mM while retaining the high calcium selectivity.  相似文献   

19.
The condensation reaction between tetraaza[14]annulene nickel(II) complex and a series of para-substituted benzoyl chlorides gave the corresponding 7,16-dibenzoylated products in 53–98% yields. The mass spectra exhibit molecular ion peaks ascribed to the 7,16-dibenzoylated products. The intense ir band due to the C?O stretching mode in these nickel(II) complexes is present in the 1650–1658 cm?1 range upon the benzoylation. Even though the ligand moiety of these six complexes is changed by benzoylation, the electronic spectra hardly vary. These nickel(II) complexes assume roughly the square-planar coordinations as judged by the ligand-field transition bands. The olefinic proton peaks at the 7- and 16-positions vanish on benzoylation in the proton nmr spectra and the proton signals of the para-substituted benzoyl groups are observed in the 2.4–8.4 ppm region. The results of the carbon-13 nmr spectra are compatible with those for the proton nmr spectra.  相似文献   

20.
Macrocycles, 7,16-diethyl-5,6,7,8,9,14,15,16,17,18-decahydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecine ( 2B ), 7,16-diethyl-5,6,7,8,9,14,15,16,17,18-decahydro-(E)dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine ( 2E ) and 7,16-diethyl-5,6,7,8,9,14,15,16,17,18-decahydro-(Z)-dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine ( 2Z ), have been synthesized by hydrogenation of 7,16-diethyl-5,14-dihydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecine and 7,16-diethyl-5,14-dihydro-(E)- or -(Z)-dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine. In each case, two isomers were produced with differing orientations of the ethyl groups relative to the macrocyclic plane. The isomers were separated by repeated recrystallization. Carbon-13 nmr spectra for the metal-free ligands were used to distinguish between the two isomers. The nickel(II), copper(II) and zinc(II) complexes of the two isomers of 2B were prepared and their spectroscopic data were determined. The ligand-field bands in the 15000–30000 cm?1 region for the nickel(II) and copper(II) complexes are consistent with square-planar configurations. A strong band appearing at ca. 3200 cm?1 in the infrared spectra was assigned to the N-H stretching mode which shifted to lower frequency upon metal coordination.  相似文献   

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