Table of Content

24 April 2003, Volume 19 Issue 2

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Articles

Synthesis, Electrocatalytic Properties and Crystal Structure of a New Organic-inorganic Hybrid Constructed from Dodecamolybdophosphoric Acid and Benzotriazole

HAN Zheng-bo, WANG Xiu-li, WANG Li, WANG En-bo, LUAN Guo-you, HU Ning-hai, JIA Heng-qing

2003, 19(2):  127-131. 

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A new compound, (C₆H₆N₃)₇(PMo₁₂^ⅥO₄₀)(PMo^ⅤMo₁₁^ⅥO₄₀)·2CH₃CH₂OH·5H₂O, was synthesized and characterized by means of elemental analyses, IR spectroscopy, ¹H NMR spectroscopy and single crystal X-ray diffraction. This is the first example of benzotriazole-polyoxometalates species. The compound crystallized in a triclinic space group P1 with a=1.8378(4) nm, b=1.9078(4) nm, c=2.1037 (4) nm, α=63.41(3)°, β=64.31(3)°, γ=68.38(3)°, V=5.803(2) nm³, Z=2, R₁=0.0486, wR₂=0.1357. The X-ray crystallographic study showed that the crystal structure was constructed by electrostatic interactions and hydrogen bonds between dodecamolybdophosphorate anions and protonated benzotriazole cations. The electrochemical behavior and the reduction of nitrite and hydrogen peroxide electrocatalyzed by the title compound were studied.

Hydrothermal Synthesis and Crystal Structure of [(CH₃CH₂)₄N]₄[(La₁₂(OH)₁₂MoO₂₉)], A Novel Cluster Compound with a MoO₅ Hexahedron Center Surrounded by La-O Octahedron

ZHANG Hong, WANG Xiu-li, LI Yang-guang, DUANG Li-ying, LAN Yang, WANG Li, WANG En-bo, HU Chang-wen

2003, 19(2):  132-134. 

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A novel compound [(CH₃CH₂)₄N]₄[(La₁₂(OH)₁₂MoO₂₉)] was synthesized by hydrothermal reaction. The single crystal X-ray diffraction shows that the compound crystallized in the monoclinic space group C2/c; a=2.5729(4) nm, b=1.4318(1) nm, c=2.1217(4) nm, β=111.56(1)°, V=6.8235(7) nm³, Z=4, R=0.0751. The basic building blocks of the crystal structure included one MoO₅ hexahedron and twelve LaO₆ octahedra which shared a common edge to form a [(La₁₂(OH)₁₂MoO₂₉)]^4- unit. These units were held together by the [(CH₃CH₂)₄N]⁺ ions.

Hydrothermal Synthesis, Structural Characterization and Properties of Mixed Valent Decavanadium Oxide [Co₂Cl₈V₁₀O₁₈(H₂O)]Cl₂·6H₂O with Novel Three-dimensional Framework

WU Ping-song, XU Lin, WANG En-bo, HU Chang-wen

2003, 19(2):  135-139. 

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Decavanadium oxide [Co₂C_l8V₁₀O_l8(H₂O)]Cl₂·6H₂O was synthesized hydrothermally with NH₄VO₃, Na₂MoO₄·2H₂O, H₃PO₄(85%), CoCl₂·6H₂O and hexamethylenetetraamine. The X-ray diffraction analysis showed that [Co₂C_l8V₁₀O_l8(H₂O)]Cl₂·6H₂O crystallized in a monoclinic crystal system, the space group was C2/m with cell parameters a=1.6065(3) nm, b=2.2699(5) nm, c=1.3897(3) nm, β= 125.29(3)°, V=4.1363(14) nm³, Z=2 and the final R=0.06, wR=0.1926. Its crystal structure is a 3-D open framework constructed by VOx polyhedra and CoCl₄ tetrahedra with channels along the crystallographic axes a, b, and c.

Preparation, Characterization and Optical Properties of Host-guest Nanocomposite Material Mordenite-silver Iodide

ZHAI Qing-zhou, QIU Shi-lun

2003, 19(2):  140-144. 

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Silver iodide nanoclusters were successfully prepared in the channels of mordenite by a heat diffusion method. Powder X-ray diffraction, adsorption technique and infrared spectroscopy were used to characterize the prepared materials, which showed that the guest silver iodide had been encapsulated in the channels of mordenite. The optical properties of the solid phase diffuse reflectance absorption of nanocomposite material NaM-AgI were studied, showing that the absorption bands of the diffuse reflectance absorption of the prepared material moved to the region of high energy. The absorption peak of the material prepared shifted to the region of high energy. Namely, blue shift was caused. This has demonstrated the incorporation of silver iodide into the channels of the zeolite. We observed the luminescence and surface photovoltage spectra of NaM-AgI sample, proposing the mechanisms of the photoluminescence and photovoltaic responses.

Syntheses and Structural Researches of Yb³⁺ Complexes with Nitrilotriacetic Acids——Nine-coordinate K₃[Yb(nta)₂(H₂O)]·5H₂O and Eight-coordinate Na₃[Yb(nta)₂]·6H₂O Complexes

WANG Jun, ZHANG Xiang-dong, JIA Wei guo, LI Hui fang

2003, 19(2):  145-150. 

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Yb³⁺ complexes with two nitrilotriacetic acid molecules were prepared and their compositions were determined as K₃[Yb(nta)₂(H₂O)]·5H₂O and Na₃[Yb(nta)₂]·6H₂O by elemental analyses. Their structures were characterized by single-crystal X-ray diffraction analyses. In complex K₃[Yb(nta)₂(H₂O)]·5H₂O, the YbN₂O₇ part forms a nine-coordinate monocapped square antiprismatic structure. In complex Na₃[Yb(nta)₂]·6H₂O, the YbN₂O₆ part forms an eight-coordinate square antiprismatic structure. It can be seen that the outer cations (K⁺ and Na⁺) greatly affect the coordination number and coordinate structure from these results.

Pseudo Peak Phenomena in Micellar Electrokinetic Capillary Chromatography by Using Ionic Surfactant

CHEN Guan-hua, YANG Geng-liang, TIAN Yi-ling, CHEN Yi

2003, 19(2):  151-154. 

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The origin of pseudo peak was studied by means of micellar electrokinetic capillary chromatography with cetyltrimethylaminium bromide as the pseudo stationary phase. It has been pointed that two peaks may appear for one component under certain conditions. Experiments showed that the relative areas of the two peaks of analyte depended on the time and the temperature of reaction between analyte and surfactant, and the concentration of surfactant in the sample solution. It means that the interaction between the analyte and the surfactant is a slow process, and a stable substance can be produced from the interaction. It is the substance and the analyte that may lead to the formation of two peaks. The fast interaction mechanism between the solute and the micellar should be queried from the experiment result.

Chemiluminescence Sensor for the Determination of Hydroxylamine by Electrostatically Immobilizing Luminol and Periodate

ZHANG Si-chun, ZHOU Guo-jun, JU Huang-xian

2003, 19(2):  155-159. 

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A novel chemiluminescence(CL) sensor, which can be used for hydroxylamine determination in combination with flow injection analysis, was developed by electrostatically immobilizing luminol and periodate on anion-exchange resin respectively. Hydroxylamine was sensed by its enhancing effect on the weak CL reaction between luminol and periodate, which were eluted from the ion exchange column. The response of the sensor to hydroxylamine was linear in the concentration range of 8.0×10^-8-2.0×10^-6 mol/L with a detection limit of 4.0×10^-8 mol/L hydroxylamine(3σ). The relative standard deviation(RSD) was 2.0% for 9 repetitive determinations at a hydroxylamine concentration of 5.0×10^-7 mol/L. The sensor could be reused for over 400 times with a good reproducibility and was used to determine hydroxylamine in wastewater.

Synthesis and Crystal Structure of N-(1'-Phenyl-2'-hydroxyethyl)-2,3-naphthylenedicarboximide

WANG Zhan-yue, DU Da-ming, WU Di, HUA Wen-ting, JIN Xiang-lin

2003, 19(2):  160-164. 

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N-(1'-Phenyl-2'-hydroxyethyl)-2,3-naphthylenedicarboximide(1a) was obtained by the reaction of 2,3-naphthylenedicarbonitrile with R-phenylglycinol. 2,3-Naphthylenedicarboxylic acid, when reacts with thionyl chloride, gives 2,3-naphthalenedicarboxylic acid cyclic anhydride rather than the corresponding 2,3-naphthalenedicarboxylic acid dichloride. The former, when reacts with S-leucinol, gives corresponding dicarboximide(1b). The crystal structure of compound 1a was determined by an X-ray single crystal diffraction analysis. Compound 1a: C₄₀H₃₀N₂O₆, F_W=634.66, orthorhombic, space group P2(1)2(1)2(1), a=1.15556(5) nm, b=3.16552(12) nm, c=0.85984(3) nm; α= 90°, β=90°, γ=90°, V=3.1452(11) nm³, Z=4, F(000)=1328, D_c=1.340 g/cm³, μ=0.091 mm^-1. Reflections collected/unique, 28053/4068(R_int=0.0411); Final R indices [I>2σ(I)]: R₁=0.0337, wR₂=0.0687; Largest diff. peak and hole, 248 and -222 e·nm^-3.

Efficient Synthesis of 2-Ethyl-A-ring Analogues of 19-Nor-1α,25-dihydroxy Vitamin D₃

WANG Qiuan, ZHAO Yu-rui

2003, 19(2):  165-173. 

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The novel 19-nor-lα,25-dihydroxy vitamin D3 analogues possessing an ethyl at the 2-position(4 and 5), were synthesized by coupling 25-hydroxy Windaus-Grundmann ketone derivative 20 with A-ring synthons(15 and 19) respectively. The enantioselective synthesis of substituted bicyclic[3,1,0] hexanes structure A-ring synthons, started from all-cis-3,5-dihydroxy-4-ethyl-1-(methoxycarbonyl)cyclohexane via lipase-catalyzd asymmetrization, was demonstrated.

Synthesis, Characterization and Properties of Bis{oxo-bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]} and Crystal Structure of Bis{oxo-bis[2-furylcarboxylatodibenzyltin(Ⅳ)]}

YIN Han-dong, WANG Chuan-hua, WANG Yong, MA Chun-lin

2003, 19(2):  174-179. 

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A series of bis{oxo-bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]} complexes {[(PhCH₂)₂Sn·(O₂CR)]₂O}₂[where R=2-furyl, 2-(2-furyl)vinyl, 2-(5-tert-butyl)furyl, 2-thiophenyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, 3-indolyl, 3-indolylmethyl, 3-indolylpropyl] was synthesized by the reactions of heteroaromatic carboxylic acids with dibenzyltin(Ⅳ) oxide. All the complexes were characterized by elemental analysis, IR, and NMR spectra. The complexes were tested against two human tumour cell lines: MCF-7 and WiDr. The results show that they have higher activities in vitro. The crystal structure of bis{oxo-bis[2-furylcarboxylatodibenzyltin(Ⅳ)]}(1) was determined by X-ray diffraction. The crystal belongs to monoclinic space group P2₁/n, a=1.6641(2) nm, b=1.25073(18) nm, c=1.7193(3) nm, β=101.951(2)°, Z=2, R₁=0.0446, wR₂=0.1100. Complex 1 is of a centrosymmetric dimer structure with a four-membered central endo-cyclic Sn₂O₂ unit in which the bridged oxygen atoms are tri-coordinated. Each bridged oxygen atom also connects with an exo-cyclic tin atom. The tin atoms are six-coordinated and have a coordination geometry of a distorted octahedron. The exo-cyclic tin atoms are five-coordinated and have a coordination geometry of a monocapped trigonal bipyramid with a very similarly distorted mode. Four carboxylate ligands are divided into two types. The two of the four carboxylate ligands are bidentate and bridged to each pair of exo- and endo-cyclic tin atoms by using both the oxygen atoms. The other two are monodentate and bridged to each pair of exo- and endo-cyclic tin atoms but each utilizes one O atom only.

A Study on Bioactivity of Corn Peptides with Low Molecular Weight(Ⅰ) ——Effect of an Intake of them on Alcohol Metabolism in Rats

XU Li, WU Xiao-xia, FEI Xiao-fang, ZHANG Li-qiang, ZHANG Xue-zhong

2003, 19(2):  180-182. 

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This study aims at the effects of an intake of low molecular weight corn peptides(LMCPs) prepared from zein on alcohol metablism in rats. LMCPs(1.0 g/kg body weight) in 15% ethanol(10 mL/kg body weight) were given to Wister rats by intragastric gavage. The assay of blood ethanol was conducted by using the enzyme-based assay kit. The amino acid analysis was made with an amino acid analyzer. The data of the animal experiments showed that LMCPs could accelerate the metabolism of alcohol in rats. In the control group, the blood ethanol concentration reached the maximum level of (827.0±77.3) mg/L after ethanol loading for 30 min, then gradually decreased. In contrast, the blood ethanol concentration only reached (527.25±47.0) mg/L after 30 min in the group of LMCPs taken. These results indicate that LMCPs could decrease ethanol concentration in blood rapidly.

Preparation of Anti-cardiac Troponin I Monoclonal Antibodies and Their Characterization with Surface Plasmon Resonance Biosensor

WEI Jing-yan, LIU Xia, SONG Da-qian, BU Li-sha, HU Xing, MU Ying, ZHANG Han-qi, LUO Gui-min, ZHANG Gui-zhen, DING Jia-hua, WANG Wei-zhong, JIN Qin-han

2003, 19(2):  183-189. 

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Cardiac troponin I(cTnI) was separated and purified from human left ventricular tissue by affinity chromatographic method and used to immunize Balb/c mice by intraperitoneal injection and four hybridoma cell lines, which secreted monoclonal antibody(mAb) against human cTnI, were obtained by cell fusion, identification and cloning twice. Three mAbs(9F5, 2F11, 8C12) were produced from the ascites of Balb/c mice injected intraperitoneally the hybridoma cells and characterized by means of a surface plasmon resonance(SPR) biosensor. An optimal and specific sensing membrane for troponin I was prepared with staphylococcal protein A(SPA) as the intermediate layer and mAb against human cTnI as the capture antibody. On the basis of the sensing membrane, two modes of operation of the SPR biosensor were developed, i.e., a direct detection of antigen-antibody affinity and a sandwich assay. In the sandwich assay detection mode, the mAbs competition was measured by monitoring whether the secondary antibody had been attached to the cTnI already captured by the first antibody on the sensor surface. The SPR biosensor was shown to be able to directly detect the antigen-antibody affinity and the order of the affinity was found to be 9F5＞2F11＞8C12. In the sandwich detection mode, it was found that the different epitopes on the cTnI molecules were recognized by the three mAbs respectively, but the asymmetrical competition was shown between 2F11 and 8C12 and no competition was found between 9F5 and 2F11 or 8c12. Based on these results, a double monoclonal sandwich immunoassay for cTnI was developed by using the optimal antibody pair of 9F5 and 2F11 and the SPR biosensor with SPA substrate membrane, which showed an excellent sensitivity of 0.8 μg/L for both the buffer and the serum samples compared with the direct detection of cTnI for the buffer with the lowest detection limit of 4 μg/L and conventional ELISA with the sensitivity of 1.9 μg/L.

Preparation of Er-Fe Alloy Films in Dimethylsulfoxide by Electrodeposition Method

LI Gao-ren, TONG Ye-xiang, LIU Guan-kun

2003, 19(2):  190-195. 

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Cyclic voltammetry and chronoamperometry were used to investigate the electrochemical behavior of Fe(Ⅱ) and Er(Ⅲ) in a LiClO₄-DMSO(dimethylsufoxide) system at Pt and Cu electrodes. Experimental results indicate that the reductions of Fe(Ⅱ) to Fe(0) and Er(Ⅲ) to Er(0) were irreversible at Pt and Cu electrodes. The diffusion coefficient and the electron transfer coefficient of Fe(Ⅱ) in a 0.01 mol/L FeCl₂-0.1 mol/L LiClO₄-DMSO system at 303 K were 1.70×10^-10 m²/s and 0.08 respectively, the diffusion coefficient and the electron transfer coefficient of Er(Ⅲ) in a 0.01 mol/L ErCl₃-0.1mol/L LiClO₄-DMSO system at 303 K were 1.47×10^-10 m²/s and 0.108 respectively. The homogeneous, strong adhesive Er-Fe alloy films containing Er of 31.39%-42.12% in mass fraction with metallic lustre were prepared by potentiostatic electrolysis on a Cu electrode in a ErCl₃-FeCl₂-LiClO₄-DMSO system at -1.75— -2.50 V(vs. SCE).

Theoretical Studies on Electronic Spectrum Property of 2-(2-Hydroxyphenyl) pyridine Via Time-dependence Density Functional Theory Method

DUAN Hong-xia, SU Zhong-min, KAN Yu-he, ZHU Dong-xia, LIAO Yi, WANG Yue

2003, 19(2):  196-200. 

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The geometrical structures of 2-(2-hydroxyphenyl) pyridine(PP) and its protonation states were optimized by means of the B3LYP/6-31G(d) method. For all the selected systems, the existence of H-bond is in favor of the stability of the systems. On the basis of the optimized geometrical structures, their electronic spectrum properties were studied by time-dependent density functional theory(TD-DFT) methosd via a hybrid function of B3LYP and 6-31G(d) basis set. The TD-DFT calculation result predicts the absorption spectrum of PP at 324 nm(3.82 eV), which is in very good agreement with the experimental value of 322 nm(3.85 eV) determined in solvent chloroform. The absorption spectra of the two protonation states both exert a red shift in various pH media.

Novel Phosphate-sensitive Fluorescent Composite Matrix

XIE Zeng-hong, LIN Xu-cong, CHEN Guo-nan

2003, 19(2):  201-205. 

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Via several techniques to modify sensitive matrix for inhabiting the leakage of fluorescent indicator, a new stable sensing material for monitoring phosphates has been prepared and applied to the measurement of phosphates in artificial seawater. It is based on the reaction of PO₄^3- with Al(Ⅲ)-Morin that leads to the fluorescence quenching of the composite matrix. At pH value 4.0 and the salinity value 25.0, the response time of output signal having reached the steady state is less than 300 seconds. Its calibration graph is gained in the range of H₂PO₄^- mass concentration from 1.50 to 7.00 μg/mL with the limit of detection(3σ/K) 0.02 μg/mL. When it was used to measure phosphates in artificial seawater, the recovery ranged from 96.78% to 102.09%. Being stored under the proper condition, the membranes maintain sensitive for 90-120 days, and are able to be used for 50-80 times with indicator supplement.

Effect of La on Partial Oxidation of Ethanol to Hydrogen over Ni/Fe Catalysts

WANG Wei-ping, WANG Zhi-fei, DING Yan, LÜ Gong-xuan

2003, 19(2):  206-210. 

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The partial oxidation of ethanol to hydrogen was investigated over Ni/Fe/La catalysts prepared by the co-precipitation method. The effects of introduction of La promoter and the reaction temperature on the catalytic performance were studied. It was found that the introduction of La into Ni/Fe catalysts is helpful to increase the selectivity to hydrogen and the stability of the catalysts. The results of XRD and XPS characterization show that the structure of the catalyst was changed during the reaction. The existence of LaFeO₃ species is possibly the main reason of the increase of the catalyst stability.

Layered Double Hydroxides with Hydrotalcite-type Structure Containing Fe³⁺, Al³⁺ and Mg²⁺

GUO Xiong-hua, LI Shu-ping, HOU Wan-guo, HAN Shu-hua, HU Ji-fan, LI Dong-qing

2003, 19(2):  211-215. 

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Layered double hydroxides(LDHs) with hydrotalcite-type structure containing Fe³⁺, Al³⁺ and Mg²⁺ were prepared by means of a coprecipitation method. The products were characterized by element analysis, X-ray powder diffraction and transmission electron microscopy. It was found that even if the molar ratio of n(Fe+Al)/n(Fe+Al+Mg)>0.33, yet a pure hydrotalcite-like compound(HTlc) phase was gained when n(Fe)/n(Al+Mg+Fe)≤0.30 and n(Al)/n(Al+Mg+Fe)≤0.30; the Al(OH)₃ phase appeared in the products when n(Al)/n(Al+Mg+Fe)>0.30; and an amorphous phase emerged when n(Fe)/n(Al+Mg+Fe)>0.33. These results show that there is no concentration superposition effect between Fe³⁺ and Al³⁺ on the crystalline state of the produced samples. In our previous work, the concentration superposition effect between Zn²⁺ and Mg²⁺ in the synthesis of Zn-Mg-Al-LDHs was found. For the prepared Fe-Al-Mg-LDHs samples, the value of lattice parameter a is between 0.30-0.32 nm; and the value of lattice parameter c is between 2.30-2.47 nm, the basal spacing is in the range of 0.76-0.83 nm. When the ratio of n(Fe)/n(Al) is a constant, the values of a and c increase with the increase of the Mg²⁺ content of the produced samples. The mean particle size and the mean crystal grain were determined by virtue of a particle-size instrument, XRD-Scherrer formula and TEM method, respectively.

Phase Transformation Mechanism of Graphite-Turbostratic Graphite in the Course of Mechanical Grinding

GAO Zhong-min, JIN Hong-zheng, LI Xiang-shan, HUA Zhong

2003, 19(2):  216-218. 

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The transformation from graphite to turbostratic graphite by means of the treatment with high-energy ball milling was investigated by X-ray powder diffraction method. It is believed that the size effect of nano-crystal leads to this transformation. A possible transformation mechanism is proposed from the change of the eletronic structure of the hexagonal plane of the carbon atoms.

Kinetics and Mechanism of Oxidation of Lactic Acid by Dihydroxyditelluratoargentate(Ⅲ) in Alkaline Medium

SHAN Jin-huan, WANG Li, LIU Bao-sheng, SHEN Shi-gang, SUN Han-wen, WANG An-zhou

2003, 19(2):  219-221. 

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The kinetics of the oxidation of lactic acid(Lac) by dihydroxyditelluratoargentate(Ⅲ)[abbreviated as DDA of Ag(Ⅲ)] anions was studied in an aqueous alkaline medium by conventional spectrophotometry in a temperature range of 25—40 ℃. The order of the redox reaction of lactic acid and DDA was found to be first-order. The rates increased with the increase in [OH^-] and decreased with the increase in [tellurate]. No free radical was detected. In the view of this the dihydroxymonotelluratoargentate(Ⅲ) species(DMA) is assumed to be the active species. A plausible mechanism involving a two-electron transfer is proposed, and the rate equation derived from the mechanism can be used to explain all the experimental results. The activation parameters(25 ℃) and the rate constants of the rate-determining step along with the preequilibrium constants at different temperatures were evaluated.

Thermal Behavior of Zn(Thr)SO₄·H₂O

LI Huan-yong, GUO Peng-jiang, HU Rong-zu, GAO Sheng-li, SHI Qi-zhen

2003, 19(2):  222-226. 

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Solid complex Zn(Thr)SO₄·H₂O was prepared in a water-acetone system. Under linearly increasing temperature, the non-isothermal kinetics and the decomposition mechanism of Zn(Thr)SO₄·H₂O were studied by means of thermogravimetry and IR spectrometry. The thermal decomposition processes of the complex could be divided into three stages. The non-isothermal decomposition mechanism and the kinetics parameters of the ligand-lost process were obtained from an analysis to the TG-DTG curves at various heating rates of 5.0, 10.0, 15.0 and 20.0 K/min by two integral and three differential methods. The results show that the random nucleation and the subsequent growth mechanism (n=3/2) controlled the ligand-lost process, the corresponding activation energy E and pre-exponential constant A are 139.96 kJ/mol and 10^11.32s^-1, respectively. The empirical kinetics model equation was constructed.

A Thermochemical Study on Complex Nickel(Ⅱ) L-α-Histidine

GAO Sheng-li, CHEN San-ping, HU Rong-zu, SHI Qi-zhen

2003, 19(2):  227-230. 

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The formation enthalpy of complex nickel(Ⅱ)-histidine(His) in water was determined by means of microcalorimetry in the temperature range of 298.15-323.15 K. The standard enthalpy of the formation of Ni(His)₂²⁺(aq) was calculated. On the basis of the experimental and the calculated results, three thermodynamic parameters(the activation enthalpy, the activation entropy and the activation free energy), the rate constants, three kinetic parameters(the apparent activation energy, the pre-exponential constant and the reaction order) of the formation reaction of the title complex were obtained.

Catalytic Effect of Cobalt and Iron Complexes Incorporating Bis(2-aldiminoethyl)amine Ligands on Ethylene Oligomerization

WANG Mei, DAI Dong, ZHU Hong-jun, WANG Hui, SUN Li-cheng

2003, 19(2):  231-234. 

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Complexes [MCl₂{CH₃N(CH₂CH₂NCR¹R²)₂}](3, M=Co, ¹=H, ²=Ph; 4, M=Fe, R¹=H, R²=Ph; 5, M=Co, R¹=R²=Ph) were prepared and characterized by IR spectra and elemental analysis. The combination of each of complexes 3-5 with ethylaluminoxane(EAO), respectively, was found to be moderately active for ethylene oligomerization to low carbon olefins. The activity of 113 kg oligomers·mol^-1 Co·h^-1 for complex 3(100 mol of EAO, 180 ℃ and 1.8 MPa ethylene) was observed with a selectivity of 93% to C_4-10 olefins, of which 96% were linear C4-10 olefins. The catalytic properties of complexes 3-5 were compared with those of analogous P,P-coordinated complexes [MCl₂{CH₃N(CH₂CH₂PPh₂)₂}](1, M=Co; 2, M=Fe).

Polybinaphthyls of (R)-3,3′-Diiodo-2,2′-binaphtho-20-crown-6 with p-Divinylbenzene via Heck Cross-coupling Reaction

LIU Tian-dong, CHENG Yi-xiang, YANG Xiao-liang

2003, 19(2):  235-238. 

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The present paper deals with the polymerization of (R)-3,3′-diiodo-2,2′-binaphtho-20-crown-6 with p-divinylbenzene under Heck-coupling reaction condition. Both the monomers and the polymer were analyzed by NMR, FTIR, UV, CD, fluorescent spectroscopy, polarimetry, GPC and elemental analysis. The polymer can emit a strong blue fluorescence and is expected to have the potential application in the polarized blue-light emitting sensors. The chiral conjugated polymer exhibits a strong Cotton effect in its Circular Dichroism(CD-) spectrum, indicating the high rigidity of the polymer backbone.

Asymmetric Cyclopropanation Catalyzed by a Copper-(Schiff-base)Complex with Double Chiral Centers

JIANG Chang-sheng, LI You-gui, JIANG Chen, WEN Ji-wu, YOU Tian-pa

2003, 19(2):  238-239. 

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A Novel Flow Injection Optical Fiber Biosensor for Hypoxanthine Based on Luminol Electrochemiluminescence

LI Ying-xiu, ZHU Lian-de, ZHU Guo-yi

2003, 19(2):  240-244. 

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A Facile Enantioselective Reduction of Acetylferrocene with Chiral Sodium Hydroboro-L-prolinate

ZHANG Jun-long, HAN Jie, WANG Yan-mei, DONG Chun-e, ZHANG Liang-fu

2003, 19(2):  245-248. 

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Characterization of Full-Biodegradable Starch-PVA-Polyester Film

RAN Xiang-hai, DENG Peng-yang, ZHUANG Yu-gang, DONG Li-song, GAO Ge, ZHAO Chun, LIU Feng-qi

2003, 19(2):  249-252. 

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