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1.
Three coordination polymers based on the V-shaped 4,4'-dicarboxybiphenyl sulfone (H2sdba) ligands, [Zn3(μ-OH)2(sdba)2]n·2nH2O 1, [Zn2(sdba)2(4,4'-bipy)]n·2nH2O 2 and [Zn3(sdba)3(py)2]n·n(py)·nH2O 3 (4,4'-bipy = 4,4'-bipydine), were hydrothermally synthesized and structurally characterized. Complex 1 features the 2D planes constructed by the sdba ligands linking infinite Zn-O-C SBUs. The 4,4'-bipy ligands in 2 bridge the Zn^II-sdba chains into interpenetrated 2D planes. The 3D network of α-Po topology in 3 is built from tri-nuclear Zn3 units with a [Zn3(OOC)6] structure. The intense blue and yellow luminescence was observed in complexes 1~3 which may result from ligand-to-metal charge transfer (LMCT).  相似文献   

2.
A novel co-ordination polymer based on IB metal thiocyanates, [Ag2(NCS)2(4,4'-bipy)]. (1)(4,4'-bipy = 4,4'-bispyridine), has been synthesized by the pre-assembly method and characterized by X-ray crystallography. The complex exists as a three- dimensional network consisting of (AgSCN). undulating layers linked by 4,4'-bipy bridges.  相似文献   

3.
Diethylstilbestrol (DES) is a synthetic estrogen that has ever been used worldwide. Polyclonal antibodies (PAbs) were used in immunoassay for detection of DES residues in environmental and agricultural samples in previous paper. In this paper, an indirect competitive enzyme-linked immunosorbent assay (icELISA) was developed based on monoclonal antibody (MAb) for the determination of diethylstilbestrol. Mono-o-carboxypropyldiethylstilbestrol (DES-CP) and mono-o-carboxymethyldiethylstilbestrol (DES-CME) were synthesized to be haptens. DES-CP was coupled to bovine serum albumin (BSA) to be an immunogen in BALB/c female mouse for MAb production. The MAb was characterized for specificity and affinity to DES in icELISA. Under the optimum condition, the icELISA showed an ICs0 of 9.8 ng/mL, the limit of detection (IC20) of 2.3 ng/mL and a working range of 2-42 ng/mL. Hexestrol and dienestrol exhibited cross-reactivity values were 44% and 27%, respectively. Cross-reactivity of natural estrogen 17β-estradiol was less than 0.1%. The influences of some factors such as salt concentration, pH and organic solvent concentration on the assay were evaluated. The concentrations of DES in the fortified water samples determined by the assay were correlated well with the fortification levels. The results were conf'm'ned with analysis by HPLC.  相似文献   

4.
Salicin-based phenolic glycosides(PGs) are important defensive substances against herbivore feeding and have good bioactivities. In this work, a novel approach for the synthesis of salicin-based PGs has been developed, by which PGs of 2'-O-acetylsaliein(5a), 3'-O-acetylsalicin(gb) and 3'-O-benzoylsalicin(Sd) were hemisynthesized. The effects of acylation reagent, solvent and temperature on the regioselective acylation of 2'- or 3'-hydroxyl groups of salicin mediated by dibutyltin oxide were investigated. The optimal conditions under which the best regioselectivity reached for 5a-5d were discovered, respectively. Moreover, a tentative tin-oxygen coordination mechanism was put forward to explain the different regioselectivities shown under different conditions.  相似文献   

5.
The title compound [Co(5-NH2-bdc)(4,4'-dpdo)(H2O)]n 1 (5-NH2-bdc = 5-aminoiso- phthalic acid,4,4'-dpdo = 4,4'-bipyridrl-N,N'-dioxide) crystallizes in triclinic,space group P1 with a = 4.999(1),b = 10.072(2),c = 13.028(3) A,α = 107.72(3),β = 92.58(3),γ = 98.11(3)°,V = 615.9(3) A^3,F(000) = 356,Rint = 0.0186,Z = 2,R = 0.0333,wR = 0.0721,S = 1.032 and (Δ/σ)max = 0.001. In the molecule of 1,the Co(II) cation is coordinated by three O-atoms of two 5-NH2-bdc ligands,one N-atom of another 5-NH2-bdc ligand,one O-atom of 4,4'-dpdo and one terminal O-atom of water molecule. The molecules construct a 2-D network through bridging 5-NH2-bdc and 4,4'-dpdo ligands,and further form a 3-D network through N–H and O–H hydrogen bonds. The network topology of 1 can be simplified as a rare 2D (3,6)-connected (426381) net.  相似文献   

6.
The one-pot hydrothermal reaction of CuCl2 with H2CPOA and 4,4'-bpy results in two new coordination polymers, [Cu(CPOA)(4,4'-bpy)(H2O)2]·1.5H2O (1) and [Cu2(HCPOA)4(4,4'-bpy)4] (2) (H2CPOA=4-carboxyphenoxy acetic acid, 4,4'-bpy=4,4'-bipyridine) since CPOA^2- anions reach equilibrium with HCPOA^- anions in the reaction system. The crystal structure of 1 shows a triple interpenetration CdSO4-like net with 1D channel, in which lattice water molecules are located. Complex 2 is a ladder-like 1D double chain structure assembled through coordination bonds and O—H…N hydrogen bonds.  相似文献   

7.
New Schiff base polymers poly[4,4'-methylenebis(cinnamaldehyde)ethylenediimine] (PMBCen), poly[4,4'- methylenebis(cinnamaldehyde)1,2-propylenediimine] (PMBCPn), poly[4,4'-methylenebis(cinnamaldehyde)1,3-propylenediimine] (PMBCPR), poly[4,4'-methylenebis(cinnamaldehyde) 1,2-phenylenediimine] (PMBCPh), poly[4,4'-methylenebis(cinnamaldehyde)meso-stilbenediimine] (PMBCS), poly[4,4'-methylenebis(cinnamaldehyde)urea] (PMBCUR), poly[4,4'- methylenebis(cinnamaldehyde)semicarbazone] (PMBCSc), poly[4,4'-methylenebis(cinnamaldehyde)thiosemicarbazone] (PMBCTSc) and poly[4,4'-methylenebis(cinnamaldehyde)hydrazone] (PMBCH) were formed by polycondensation of 4,4'- methylenebis(cinnamaldehyde) with ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,2-phenylenediamine, meso-stilbenediamine, urea, semicarbazide, thiosemicarbazide and hydrazine, respectively. The dialdehyde and polymers have been characterized through elemental micro-analysis, IR, UV-Vis and ^1H-NMR spectroscopic techniques. Thermoanalytical studies and viscous flow of dilute solutions of dialdehyde and its polymers have been examined and compared.  相似文献   

8.
Two new rotenoids 4',5'-dihydroxy-6a,12a-dehydrodeguelin (1),11.4t,5'-tdhydroxy-6a,12a-dehydrodeguelin (2), along with two known rotenoids rotenone and deguelin were isolated from the root of Derris elliptica collected in Guangdong Province, China. Their structures were established by extensive spectroscopic analysis.  相似文献   

9.
The structures of 2,7'-(ethylene)-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7'-(ethylene)-bis-8-hydroxyqulnoline and its derivatives were optimized by CIS/6-31G(d). The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory (TD-DFT) by the B3LYP method with the 6-31G(d) basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline.  相似文献   

10.
Two new 1,3-dithiole derivatives, 4,4'-{9-[4,5-bis(methylthio)-1,3-dithiol-2-ylidene]-9H-fluorene-2,7- diyl} dipyridine(2a) and 3,3'-{9-[4,5-bis(methylthio)-1,3-dithiol-2-ylidene]-9H-fluorene-2,7-diyl} dipyridine(2b) were synthesized and characterized by Fourier transform infrared(FTIR), 1H NMR, 13C NMR and mass spectroscopies. The crystal structure of compound 2b was also studied. The optimized conformations and molecular orbital diagrams of compounds 2a and 2b were illustrated via density functional theory(DFT). By the time-dependent DFT(TD-DFT) method, electronic absorption spectra of compounds 2a and 2b were predicted and the results achieved were in good agreement with the experimental data. The formation of the cationic radical during the electrochemical oxidation process was also proposed.  相似文献   

11.
Amphiphilic polypyridyl mthenium(Ⅱ) complex cis-di(isothiocyanato)(4,4'-di-tert-butyl-2,2'-bipyridyl)(4,4'- dicarboxy-2,2'-bipyridyl)ruthenium(Ⅱ)(K005) has been synthesized and characterized by cyclic voltammetry, ^1H NMR, UV-Vis, and FT-IR spectroscopies. The sensitizer sensitizes TiO2 over a notably broad spectral range due to its intense metal-to-ligand charge-transfer (MLCT) bands at 537 and 418 nm. The photophysical and photochemical studies of K005 were contrasted with those of cis-Ru(dcbpy)2(NCS)2, known as the N3 dye, and the amphiphilic ruthenium(Ⅱ) dye Z907. A reversible couple at E1/2=0.725 V vs. saturated calomel electrode (SCE) with a separation of 0.08 V between the anodic and cathodic peaks, was observed due to the Ru^Ⅱ/Ⅲ couple by cyclic voltammetry. Furthermore, this amphiphilic ruthenium complex was successfully used as sensitizers for dye-sensitized solar cells with the efficiency of 3.72% at the 100 mW·cm^-2 irradiance of air mass 1.5 simulated sunlight without optimization of TiO2 films and the electrolyte.  相似文献   

12.
A new Diels-Alder type adduct mongolicin G (1) and a new flavone 5'-(1", 1"-dimethylallyl)-5,7,2',4'-tetrahydroxyflavone (2) were isolated from the stem and root bark of Morus mongolica. Their structures were determined by spectroscopic analysis and chiroptical methods.  相似文献   

13.
王蕊林海  林华宽 《中国化学》2007,25(11):1646-1651
Two long-chain multidentate ligands: 2,9-di-(n-2',5',8'-triazanonyl)-1,10-phenanthroline (L^1) and 2,9-di- (n-4',7',10'-triazaundecyl)-1,10-phenanthroline (L^2) were synthesized. The hydrolytic kinetics of 2-hydroxypropyl p-nitrophenyl phosphate (HPNP) catalyzed by the complexes of L^1 or L^2 with La(Ⅲ) or Gd(Ⅲ) have been studied in aqueous solution at (298.2±0.1) K, I=0.10 mol·dm^-3 KNO3 in pH 7.5-9.1, respectively, finding that the catalytic effect of GdL^1 was the best among the four complexes for hydrolysis of HPNP. Its kLnLH-1, kLnLand pKa are 0.047 mol^-1·L·s^-1, 0.000074 mol^-1·L·s^-1 and 8.90, respectively. This paper expounded the studied result with the structure of the ligands and the properties of the metal ions, and deduced the catalysis mechanism.  相似文献   

14.
Two charged donor-acceptor [2]catenanes were synthesized by the cyclization of the π-acceptor 1,1 '-[1, 4-phenylenebis-(methylene)]bis(4,4'-bipyridinium)bis(hexafluorophosphate)(2) and bis(bromomethyl)benzene with the templates of the π-donor phenylene-diacetylene crown ethers la and lb in the yields of 31%, 35%, respectively. The mass spectra, 1H and 13C NMR spectra confirm that the phenylene-diacetylene crown ethers, with a nonaromatic ~r-system, successfully template the cyclization of CBPQT4+. The X-ray crystallography analysis shows that the CBPQT4+ ring encircles around the phenylene motif of the crown ethers, leaving the 1,3-butadiyne fragment out of the cavity of CBPQT4+ ring. The mechanically interlocked structure of [2]catenanes was stabilized by the cooperative effects of π-stacking and hydrogen bonding interactions.  相似文献   

15.
A kind of highly organsoluble polyimide and copolyimides were successfully synthesized from bicyclo(2.2.2)-oct- 7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA), the commercial diamine 4,4'-methylenedianiline (MDA) and the designed diamine 4,4'-methylenebis-(2-tert-butylaniline) (MBTBA). The polyimide from BCDA and MBTBA is highly soluble in conventional low boiling point solvents (such as chloroform, tetrahydrofuran) at room temperature. But the solubility of the copolyimides in conventional solvents decreased with the molar ratio of MBTBA and MDA decreased. When the molar ratio of MBTBA and MDA was larger than 7/3, the copolyimides can be soluble in low boiling point solvents at room temperature to form a transparent, flexible, tough film by solution casting. When the molar ratio of MBTBA and MDA was between 7/3 and 1/9, they can only be soluble in hot dipolar aprotic solvents (such as DMF, NMP etc.) and form films too. The copolyimide was only soluble in m-cresol when the molar ratio of MBTBA and MDA was lower than 1/9. The number-average molecular weights of the soluble copolyimides were larger than 5.8 × 1064 g/mol by GPC and their polydispersity indices were higher than 1.4. Only one glass transition temperature of these copolyimides was detected around 400℃ by DMA. The copolyimides did not show appreciable decomposition up to 430℃ in N2.  相似文献   

16.
《中国化学》2006,24(9):1259-1262
Reaction of the oligo(phenylenevinylene) 4,4'-bis(2,5-dimethylstyryl)biphenyl (bdb) with CF3CO2Ag in benzene gave a novel octanuclear sandwich cluster [Ags(bdb)2(C6H6)2(CF3CO2)8]·2C6H6 (1). The clusters are packed on each other through strong n-n interactions to form ^1D 'brick' chains, between which the solvated benzene molecules are located. TG analysis showed that cluster 1 could completely liberate the guest benzene molecules at 105℃ and the coordinated benzene molecules at 180 ℃. In solid state, cluster 1 exhibits fluorescence, and the emission band is red-shifted compared with that of free ligand bdb.  相似文献   

17.
Four chiral polymers P-1, P-2, P-3 and P-4 were synthesized by the polymerization of (S)-2,2'-dioctoxy-1,1'- binaphthyl-6,6'-boronic acid (S-M-3) with (S)-6,6'-dibromo-1,1'-binaphthol (S-M-1), (R)-6,6'-dibromo-1,1'- binaphthol (R-M-1), (S)-3,3'-diiodo-1,1'-binaphthol (S-M-2) and (R)-3,3'-diiodo-1,1'-binaphthol (R-M-2) under Pd-catalyzed Suzuki reaction, respectively. All four polymers can show good solubility in some common solvents due to the nonplanarity of the polymers in the main chain backbone and flexible alkyl groups in the side chain. The analysis results indicate that specific rotation and circular dichroism (CD) spectral signals of the alternative S-S chiral polymers P-1 and P-3 are larger than those of S-R chiral polymers P-2 and P-4, but their UV-Vis and fluorescence spectra are almost similar. The results of asymmetric enantioselectivity of four polymers for diethylzinc addition to benzaldehyde indicate that catalytically active center is (R) or (S)-1, 1'-binaphthol moieties.  相似文献   

18.
Polychelates of Mn(Ⅱ), Fe(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ) and Cd(Ⅱ) with the bis salen-type ligand derived from 4,4'-bis[(salicylaldehyde-5)azo]biphenyl and 1,4-diaminobutane have been synthesized. All the polychelalls have been characllrized by elemental analysis, magnetic susceptibility measurements, IR, electronic spectra and thennogravirncuic studies. All the complexes isolated in solid stall are dark coloured and insoluble in water and common organic solvents. The ligand behaves as a bis-bidentall molecule coordinating through the phenolic oxygen and azomethine nitrogen atoms. The thermal decomposition of these metal complexes was investigated by thermogravimetric analysis and data have been analyzed for kinetic parameters using Broido equation. The solid-state electrical conductivity of the ligand and its polychelalls in the form of compressed pellet was studied in the temperaturc range from 313 to 413 K All the polychelalls were found to show semiconducting nature. The Mn(Ⅱ), Fe(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) polychelalls have been assessed for the catalytic epoxidation of styrene.  相似文献   

19.
Imidazole-containing polyimide/silica(PI/SiO2) hybrid films were prepared from 3,3',4,4'-biphenyltetra- carboxylic dianhydride(BPDA) and 2,2'-di(p-aminophenyl)-5,5'-bibenzimidazole in N,N-dimethylacetamide(DMAc) by sol-gel method and thermal imidization. The hybrid film with high silica mass fraction up to 40% was transparent. Scanning electron microscope(SEM) and transmission electron microscope(TEM) results of the film indicate a ho- mogeneous dispersion of silica nanoparticles in the polyimide matrix. One hybrid film PI/SiO2 with 15% SiO2 exhi- bits better mechanical properties with a tensile strength of 222 MPa, an elongation at break of 12%, and a tensile modulus of 5.66 GPa. The reinforced mechanism on mechanical Drooerties was also studied.  相似文献   

20.
Two novel donor-acceptor (D-A) copolymers containing dithienosilole (DTS) donor unit and ketone modified thieno[3,4-b]thiophene (TT) acceptor unit, namely, poly{4,4'-bis(2-ethylhexyl)dithieno[3,2-b:2',Y-d]silole-5,5'-diyl- alt-l-(thieno[3,4-b]thiophen-2-yl)-2-ethylhexan-l-one} (PDTSTT) and poly{4,4'-bis(2-ethylhexyl)dithieno[3,2- b:2',3'-d]silole-5,5'-diyl-alt- 1-(4,6-bis(4-ethylhexylthien-2-yl)thieno[3,4-b]thiophen-2-yl)-2-ethylhexan- 1-one} (PD- TSDTTT), were synthesized for the application in polymer solar cells (PSCs), and the effects of thiophene bridge on the structural geometry and photovoiltaie performance have been investigated. The polymer PDTSTT and PDTSDTTT have the electrochemical bandgaps of 1.54 and 2.02 eV, together with low-lying HOMO energy levels of-5.47 and -5.37 eV, respectively. Molecular geometry simulation result shows that compared with PDTSTT, the insertion of thiophene bridge in PDTSDTTT can well relieve the steric hindrance between the TT and DTS unit, as confirmed by the reduced dihedral angle between DTS and DTTT unit. Under the illumination of AM 1.5G, 100 mW/cm2, the PSC based on PDTSDTTT/PC61BM (1 : 1, w : w) demonstrates a power conversion efficiency of 1.0%, which is significantly improved in comparison with the device based on PDTSTT/PC61BM (1 : 2, w : w) under the same experimental condition. This is because the enhanced planarity and increased effective conjugation of the main chain in PDTSDTTT promote the more favorable morphology for charge transportation, although PDTSTT possesses the broader absorption band than PDTSDTTT.  相似文献   

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