中国化学快报

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The Application of Allyl as a Protecting Group in the Preparation Of Dinucleoside Carbonate

Ying ZHOU, Liang Ren ZHANG, Li He ZHANG

中国化学快报. 1998, 9(09): 791-793.

摘要 ( )

可视化

Reaction of 5'-O-p-methoxytritylthymidine with 1,1'-carbonyl-diimidazole gave the 3'-O-carbonylimidazolide, which was condensed in high yield with 3'-0-protected thymidine to give a dinucleoside carbonate. In the synthesis of dinucleoside carbonate, allyl can be used as a good protecting group for 3'-hydroxyl of thymidine. The condition of deprotection will not affect the carbonate bridges.

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One-step Beckmann Rearrangement from Ketones and Hydroxylamine in Dry Media under Microwave Irradiation

Jun Cai FENG, Bin LIU, Li DAI, Ning Sheng BIAN

中国化学快报. 1998, 9(09): 795-796.

摘要 ( )

可视化

Ketones react with hydroxylamine hydrochloride over HC00H/Si0₂ under microwave irradiation to afford amides in good yields.

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A New Synthetic Route for 2,4-Dibromo-5-fluorobenzoic Acid

Qiong ZHENG, Chi HUANG, Chong Wen XU, Guang Yong XIE, Gao Qing CHEN, Yuan Yin CHEN

中国化学快报. 1998, 9(09): 797-798.

摘要 ( )

可视化

A convenient and practical synthetic route for 2,4-dibromo-5-fluorobenzoic acid is described. Two intermediates, 2,4-dibromo-5-fluorobenzonitrile and 2,4-dibromo-5-fluoro-benzamide, have not been reported before. This route can be easily industrialized.

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Regioselective Synthesis of Two Novel 4-alkenyloxy-2,6-dihydroxyacetophenones

Chu Sheng HUANG, Zhe ZHANG, Shu Hua LI, Yu Lin LI

中国化学快报. 1998, 9(09): 799-800.

摘要 ( )

可视化

Two novel Acetophenones, 4-(1'-geranyloxy)-2,6-dihydroxyacetophenone 1 and 4-(1'-farnesyl)-2,6-dihydroxyacetophenone 2 isolated from the fruit of Evodia merrillii and from the aerial parts of Borronia ramosa respectively, have been synthesized by starting from 2,4,6-trihydroxyacetophenone 3.

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A Novel Synthesis of Isoxazole Derivatives

Jun Feng WANG, Bao Shan DU, Qing Hua CHEN

中国化学快报. 1998, 9(09): 801-802.

摘要 ( )

可视化

The new synthetic method of isoxazole derivatives was succesfully achieved. The experimental results demonstrate that thermal decomposition reactions of nitrone could take place with yields of 41~81%, to give a series of new isoxazole derivatives.

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Formation of 3-Arylpyrazolines and 1-Aroylethyl-3-arylpyrazolines via 3-Aroylethylsydnone with HCl in Ethyl Acetate

Zhan Bin ZHANG, Cheng Lie YIN, Yong Ren WU

中国化学快报. 1998, 9(09): 803-804.

摘要 ( )

可视化

Treatment of 3-aroylethylsydnone 1 with HC1 leads to 3-arylpyrazoline 2 or 1-aroylethyl-3-arylpyrazoline 3 under different conditions.

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An Efficient and Convenient Cyclization Method for the Synthesis of Flavans

Li Ming HOU, Chu Sheng HUANQ, Yng LI, Yu Lin LI

中国化学快报. 1998, 9(09): 805-807.

摘要 ( )

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A convenient cyclization method for the flavans synthesis is described. BF₃ was used for the first time as an efficient catalyst to effect the cyclization of 1,3-diarylpropan-l-ols.

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Accelerated Approach to the Synthesis of Fluoriated Polyether Dendrimers

Xiao Ping CAO, Xiao Hong LI, Hak Fun CHOW, Ying LI

中国化学快报. 1998, 9(09): 809-812.

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可视化

Fluorinated polyether dendritic sectors 4,7 and 10 from the first to the third generations, respectively, were prepared by a convergent approach from readily available pentafluorophenol, phloroglucinol and 1,3-dibromopropane. These dendritic sectors have good solubility properties and are stable in both acidic and basic media. Hence they are useful dendritic building blocks for the preparation of functional dendrimers.

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Convenient Synthesis of Host Molecule Containing Se-Se Bond

Wei Jun KE, Xiu Fang LIU, Han Shang XU

中国化学快报. 1998, 9(09): 813-814.

摘要 ( )

可视化

Key intermediate bis[2-amino-4,5-(15-crown-5)phenyl]diselenide was obtained by the convenient redox method. Crown-ether type host molecule containing Se-Se bond 2,11-dioxo-4,5:8,9-di(benzo[4',5']-15-crown-5)-6,7-diselena-3,10,16-triazabicyclo[10,3,l]hexadeca-1(16), 4, 8,12, 14-pentaene was synthesized with high dillution technique.

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Synthesis of Spirobenzopyrans Carrying a Monoaza-benzo-15-C-5 at the 8-position

Sheng Hua LIU, Cheng Tai WU

中国化学快报. 1998, 9(09): 815-816.

摘要 ( )

可视化

Synthesis of spirobenzopyrans bearing monoazacrown at the 8-position is described.

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A Facile Synthesis of 6β-Hydroxy-7α(H)-eudesma-4-en-3-one

Gang ZHOU, Zhao Ming XIONG, Yong Gang CHEN, Yu Lin LI

中国化学快报. 1998, 9(09): 817-818.

摘要 ( )

可视化

A stereoselective total synthesis of 6β-hydroxy-7α(H)-eudesma-4-en-3-one 1 starting from (+)-dihydrocarvone 7 has been described.

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Studies on the Total Synthesis of the Repeat Unit of Candida kefyr IFO 0586 Strain

Ping Yu DING, Cheng He ZHOU, Wu Yan ZHANG, Meng Shen CAI

中国化学快报. 1998, 9(09): 819-822.

摘要 ( )

可视化

The repeat unit of Candida kefyr IFO 0586 strain was designed, and a protected pentasaccharide was synthesized by thirteen-step reactions. Trichloroacetoxy was used as leaving group at anomeric carbon.

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Photooxidation of α-Tocopherol in Micelles. A New Singlet Oxygen Oxidation Product

Wei YU, Li YANG, Zhong Li LIU

中国化学快报. 1998, 9(09): 823-826.

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可视化

Methylene blue sensitized singlet oxygen oxidation of dl-a-tocopherol in dodecyl sulfate (SDS) or cetyl trimethyl ammonium bromide (CTAB) micelles led to the formation, besides a-tocopherol quinone and its epoxide, of a hitherto unknown spiro compound 6-hydroxy-2,6,8,9-tetramethyl-2-phytyl-1-oxaspiro[4,5]dec-8-en-7,10-dione.

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Terminalic Acid, a New Tannin from the Fruit of Terminalia chebula

Yan Ze LIU, Bing Wu YU, Gang DING, Yang jie WU

中国化学快报. 1998, 9(09): 827-828.

摘要 ( )

可视化

Terminalic acid 1, a new hydrolysable tannin, was isolated from the fruit of Terminalia chebula. Its structure was found to be l-0-galloyl-2,4-chebuloyl-β-D-glucopyranose by chemical method and ¹HNMR, ¹³C-NMR, ¹H-¹H COSY, HMQC, HMBC and FAB-MS spectral analyses.

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Artselenoide, a New Dimeric Guaianolide from Artemisia selengensis

Jin Feng HU and Xiao Zhang FENG

中国化学快报. 1998, 9(09): 829-832.

摘要 ( )

可视化

A new dimeric guaianolide, artselenoide, was isolated from Artemisia selengensis. Its structure was elucidated by spectroscopic methods.

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Novel Antifungal Antibiotic, WB Produced by the Fungus Strain 38

Jun YANG, Xiu Lan QI, Gang SHAO, Yue Hu PEI, Xin Sheng YAO, Susumu KITANAKA

中国化学快报. 1998, 9(09): 833-834.

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WB, a new antifungal antibiotic, was isolated from the soil fungus strain 38 against Pyricularia oryzae, and its structure was elucidated as 2-[(E)-3,5-dimethyl-3,4-dihydroxy-1-eptylenyl]-4-chloro-5-oxo-6-methyl-6,7-dihydroxy-5,6,7,7,-4H-benzo[d]-2H-pyran on the basis of ¹H-NMR, ¹³C-NMR, DEPT, HMQC, ¹H-¹³H COSY, HMBC spectra.

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Optical Properties of Fullerenated Poly(epoxy propyl carbazole)

Tao GU, Wan Xi CHEN, Zhu De XU

中国化学快报. 1998, 9(09): 835-837.

摘要 ( )

可视化

The optical properties of the fullerenated poly(epoxy propyl carbazole) (PEPC) have been investigated. Compared with pure PEPC, fullerenated PEPC has the same structure in the UV region of the absorption spectrum, and extends the active range to a longer wavelength. The apparent quenching of PEPC fluorescence was observed in the fullerenated polymer and it can be attributed to intramolecular excited state energy transfer.

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Determination of Melatonin in the Mian Erkang Capsules by HPLC

Qing Tao PENG, Pei Rang CHEN, Wen Xiang HU, Sheng Jian TAN

中国化学快报. 1998, 9(09): 839-842.

摘要 ( )

可视化

The Mian Erkang capsules made by us is a high potency calcium preparation with actions of hypnosis and anti-decrepitude. Melatonin is one of the main effective components which can hypnotize, calm, relieve pain, increase the body's immunity, be used for cancer therapy, and delaydecrepitude. A rapid, sensitive, and accurate HPLC method for the determination of melatonin in Mian Erkang capsules is described in this paper.

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Flow-injection Chemiluminescence Determination of Catecholamines

Jia Chu HUANG, Cheng Xiao ZHANG, Zhu Jun ZHANG

中国化学快报. 1998, 9(09): 843-845.

摘要 ( )

可视化

A flow injection chemiluminescence (CL) method for the determination of catecholamines is described which is based on their inhibition of the intensity of CL from the luminol-hypochlorite system. The hypochlorite was electrogenerated on-line by a constant current electrolysis, resulting in the elimination of the instability of the hypochlorite solution prepared from a commercial reagent of sodium hypochlorite. The detection limits are 0.6 ng/ml for dopamine, 0.8 ng/ml for adrenaline and isoprenaline. The proposed method has been successfully applied to the determination of catecholamines in pharmaceutical injections.

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Polysiloxane with Pendant [60]Fulleropyrrolidines as Stationary Phase for Capillary Gas Chromatography

Ying LIU, Xun Gao ZHANG, Han Ying YE, Zhao Rui ZENG, Han Ying YE, Rong Sheng SHENG

中国化学快报. 1998, 9(09): 847-850.

摘要 ( )

可视化

Polysiloxane with pendant [60] fulleropyrrolidines was synthesized and used as the stationary phase for capillary gas chromatography for the first time. A preliminary investigation of its property shows that it has an excellent thermostability and a wide range of allowable operating temperature from 80℃ to 360℃.

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In-situ FTIR Spectroelectrochemical Study of Chromium Hexacyanoferrate on Glassy Carbon Electrode

Ai Li BO, Xiang Qin LIN

中国化学快报. 1998, 9(09): 851-854.

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可视化

Chromium hexacyanoferrate (CrHCF) modified glassy carbon electrode (GC) in different electrolytes was studied by cyclic voltammetry and in situ FTIR spectroelectrochemistry. The results indicate that the behavior of CrHCF film can be understood in term of two structures: Cr_1/3Cr(Ⅲ)Fe(Ⅱ)(CN)₆ and MCr(Ⅲ)Fe(Ⅱ)(CN)₆. Besides, the film exists in amorphous state: the outer layer is porous film, while the inner layer is relatively compact. According to the electrochemical reaction of CrHCF, the lattice can contract and expand with the cations' diffusion.

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Ab Initio Study of the Oxygen Atom Abstracting Hydrogen from Difluoromethane and Dichloromethane

Jian Hua ZHOU, Jing Zhong GUO, Xiao Ping ZHANG, Hong Ming YIN, Chuan Pu LIU, Yue Shu GU

中国化学快报. 1998, 9(09): 855-857.

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可视化

The three potential surfaces for reactions of the O atom to abstract H atoms from CH₂F₂ and CH₂Cl₂ were studied using the ab initio method. The frequencies, geometries and energies of all species are calculated. The best estimates of the heat of reactions are 30.92 KJ/mol and 13.01 KJ/mol, and, the best potential barrier heights for both reactions are calculated to be 74.50 KJ/mol and 67.22 KJ/mol, respectively, the second-order rate coefficients calculated are 2.8721×10^-21 and 4.2522×10^-20cm₃/molecule-s at 298 K, respectively.

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The Inner-sphere Reorganization Energy of M-H/M⁺-H System in Gaseous Phase

Zheng Yu ZHOU, Chuan Song ZHANG, Jian Xia YE

中国化学快报. 1998, 9(09): 859-862.

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可视化

A new ab-initio method of computing reorganization energy (RE) for the electron transfer (ET) reaction between M-H and M⁺-H system is presented. Values of RE from precise RE definition and the George-Griffith-Marcus (GGM) model were obtained and compared with the RE obtained from the experimental spectroscopic data. Results show that in the gaseous phase, ET reactions by the new method can give better values than classical GGM model.

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Studies on the Kinetics of the FO+CO Reaction

Bao Shan WANG, Hua HOU, Yue Shu GU

中国化学快报. 1998, 9(09): 863-866.

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可视化

Two competitive channels of the reaction of FO with CO were calculated by the TST-RRKM theory and the classical transition state theory, respectively. The results show that the direct channel dominates the reaction over the entire studied temperature range and the addition-elimination channel has important contributions at low temperatures. The cited reaction does not influence the fluorine regeneration and the sink of CO in the stratosphere.

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Non-equilibrium Thermodynamic Analysis of The Transport Properties of Formed-in-Place Zirconium (Ⅳ) Hydrous Oxide-Polyacylate Membranes in aqueous NaNO₃ solution

Jia Zhen YANG

中国化学快报. 1998, 9(09): 867-868.

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可视化

Nanofiltration of aqueous NaN0₃ solution with a dynamically formed Zr(IV) hydrous oxide-PAA membrane is presented. The practical transport coefficients Lp, σ, ω were obtained using relationships of the non-equilibrium thermodynamics and were used to calculate the frictional coefficients of a friction model.

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Novel Aluminoxanes Prepared from AlEt₃/Al(i-Bu)₃ Mixture as Cocatalyst for Metallocene Catalyzed Ethylene Polymerization

Zhi Qiang FAN, Qi WANG, Jian Hua WENG, Lin Xian FENG

中国化学快报. 1998, 9(09): 869-872.

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可视化

Aluminoxanes containing both ethyl and wo-butyl groups were synthesized by the hydrolysis of Al(C₂H₃)₃ (TEA)/A1(i-C₄H₉)₃ (TIBA) mixtures. The aluminoxane made from the TCA/TIBA mixture of molar ratio 7:3 showed cocatalyst activity of about five times as those of ethylaluminoxane or isobutylaluminoxane for ethylene polymerization catalyzed by Cp₂ZrCl₂. The aluminoxane was characterized and the possible reasons for its high activity were discussed.

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Doping Effect of CuO on CeO₂ for CO Oxidation

Ji Jun ZHANG, Neng LI, Ying Jun LIU, Bing Xiong LIN

中国化学快报. 1998, 9(09): 873-876.

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可视化

Cu-Ce-0 catalysts, prepared by the amorphous citrate precursor (ACP) method, were investigated by ICP, XRD and micro-reactor techniques. At low copper content of Cu-Ce-0 catalysts, fluorite structures formed at low calcining temperatures, and CuO doped into the CeO₂ matrix; at high copper content, in addition to the fluorite structure, crystalline monoclinic phase CuO formed as well at high calcining temperatures. There was no other phase formed even calcined at 1000℃. The results show that only a little CuO dopes into the CeO₂ matrix to form complex oxide, which promotes the catalytic activity of CO oxidation greatly. The optimum Cu-Ce-0 catalyst is composed of 15% copper by Cu/(Ce+Cu) atomic ratio, and calcined at 700℃ for 4h. The phase compositions include the crystalline CuO and the active complex oxide with fluorite structure. The formulation of the active complex oxide is Cu_0.06Ce_0.94O_1.94.

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A New High Efficiency Green Luminescent Material—the System Al₂O₃-B₂O₃ Containing Ce³⁺ and Tb³⁺ Ions

Hong Peng YOU, Guang Yan HONG

中国化学快报. 1998, 9(09): 877-880.

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可视化

To obtain high efficiency luminescent materials, the system Al₂O₃-B₂O₃ containing Ce³⁺ and Tb³⁺ ions with variation of B₂0₃-content, has been prepared by Al₂0₃, H₃B0₃, Ce0₂ and Tb₄0₇ under reducing atmosphere at 1250;æ. It is notable that the brightness of the sample with appropriate composition is similar to that of commercial phosphorous containing Ce³⁺ and Tb³⁺, indicating that a new high efficency green luminescent material was obtained with appropriate B₂0₃-content.

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x-ray Crystal Structure of a Dinuclear Zinc(Ⅱ) Complex with Unusual Two Monodentate O-coordination of Carboxylate Group of Isonicotinate

Feng Mei NIE, Ru Ji WANG, Yan Mei LI, Yu Fen ZHAO, Munirathinam NETHAJI, Akhil R. CHAKRAVRTY

中国化学快报. 1998, 9(09): 881-884.

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可视化

Reaction of Zn(Cl0₄)₂·6H₂O with septadentate 2,6-bis[bis(2-benzimidazolyIme-thyl) amino methyl]-4-methylphenol(Hbbap) and sodium isonicotinate yielded a dinuclear zinc complex [Zn₂(bbap) (Iso) (Hiso)] (ClO₄)₂·[Zn₂ (bbap) (Iso) (H₂0)] (ClO₄)₂·4H₂0(la·lb·4H₂0). Hiso is isonicotinic acid and Iso is isonicotinate anion. The structure has been established by X-ray crystallography and shows that the two zinc ions are bridged by the phenoxy unit of bbap ligand, and the presence of unusual monodentate O-coordination of carboxylate group from isonicotinic acid. The coordination geometry around the zinc ion is approximately trigonal bipyramidal.

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1998年, 第9卷, 第09期　刊出日期：1998-09-20

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1998年, 第9卷, 第09期 刊出日期：1998-09-20

1998年, 第9卷, 第09期　刊出日期：1998-09-20