中国化学快报

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A Novel Synthesis of Diethyl Malonate

Wei Hong SONG, Xuan Zhen JIANG

中国化学快报. 2000, 11(12): 1035-1036.

摘要 ( )

可视化

A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reaction temperature and different bases on the yield of diethyl malonate are also discussed.

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Bismuth Mediated Organic Reaction:A Convenient Method for the Synthesis of Allylic (Benzylic) Selenides and α-Organylselenocarbonyl Compounds in Aqueous Media

Pei Pei SUN, Ya Ping XIAO, Bao Chuan SHI

中国化学快报. 2000, 11(12): 1037-1040.

摘要 ( )

可视化

In the presence of BiCl₃/Al or BiCl₃/Fe, in THF-H₂O, allylic (benzylic) bromides or α-bromoketones react with diorganyl diselenides to give allylic (benzylic) selenides or α-organylselenocarbonyl compounds respectively in moderate to good yields.

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Studies on Agarofurans V. Studies on the Reductive Ring-Opening of 3,4-Epoxide of Agarofurans

Wu Yan ZHANG, Ji Yu GUO, Xiao Tian LIANG

中国化学快报. 2000, 11(12): 1041-1044.

摘要 ( )

可视化

Reduction of epoxides 1, 2, 3 with LAH and LAH/AlCl₃has been studied. The products of reduction with LAH were controlled by steric and stereoelectronic effects. The reduction with LAH/AlCl₃seemed to involve an intermediate in which one aluminum ion was shared by both oxygen atoms from the epoxide and the tetrahydrofuran ring.

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Mimetic Preparation of Analogues of Territrem B, A Potent Acetylcholinesterase Inhibitor

Yu ZHAO, Yuan Ling KU, Shoei Sheng LEE

中国化学快报. 2000, 11(12): 1045-1048.

摘要 ( )

可视化

A mimetic synthesis of a potent acetylcholinesterase inhibitor, Territrem B, was carried out from the naturally occurring jujubosides. The anti-AChE activity of the product, which possesses the 2-en-1-one pharmacophore and the aromatic ring, was measured. The aromatic ring moiety seemed to be less influencing when comparing with the 2-en-1-one moiety.

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New Soluble Fluorinated Polyimides

Kun XIE, Shu Ying ZHANG, Jin Gang LIU, Min Hui HE, Shi Yong YANG

中国化学快报. 2000, 11(12): 1049-1052.

摘要 ( )

可视化

The synthesis and properties of a class of soluble fluorine-containing aromatic polyimides are described. The polyimides show desirable features of materials for microelectronics applications.

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Dioxygen Affinities and Biomimetic Catalytic Performance of Transition-metal Complexes with Crowned Bis-Schiff Bases

Xiao Xia LU, Hong Bo LI, Wei ZENG, Hua YANG, Sheng Ying QIN

中国化学快报. 2000, 11(12): 1053-1056.

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The dioxygen affinities and biomimetic catalytic performance of transition-metal complexes with (15-crown-5) salophen and its substituted derivatives were examined. The oxygenation constants of Co(Ⅱ) complexes with crowned bis-Schiff bases were measured and their Mn(Ⅲ) complexes were employed as models to mimic monooxygenase in catalytic epoxidation of styrene. The highest conversion and selectivity were up to 57.2% and 100% respectively at ambient temperature and pressure. The effects of crown ether ring and substituents R on the dioxygen affinities and catalytic activities were also investigated through comparing with the uncrowned analogues.

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³¹P NMR Study on Some Phosphorus-Containing Compounds

Zhen XU, Ji Liang SHI, Xin CHEN, Xi Kui JIANG

中国化学快报. 2000, 11(12): 1057-1060.

摘要 ( )

可视化

³¹P NMR has become a widely applied spectroscopic probe of the structure of phosphorus-containing compounds. Meanwhile, the application of ³¹P NMR has been rapidly expanded to biochemistry and medicinal chemistry of phosphorus-containing compounds because the growing importance of the phosphorus compounds is now widely realized. We report here the results of ³¹P NMR study on some phosphorus-containing compounds, namely, O-alkyl O-4-nitrophenyl methyl phosphonates with different alkyl chain-length (MePO-n), 4-nitrophenyl alkylphenylphosphinates with different alkyl chain-length (PhP-n), diethyl phosphono-acetonitrile anion and diethyl phosphite anion. Our results indicate that ³¹P NMR can not only be applied to not only the study of the hydrolytic reactions of MePO-8 and PhP-8 but also be applied to the study of the presence of the anions of diethylphosphonoacetonitrile and diethyl phosphite in nucleophilic reactions.

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Gnetuhainin P, a New Isorhapontigenin Dimer from the Lianas of Gnetum hainanense

Ying Hong WANG, Kai Sheng HUANG, Mao LIN

中国化学快报. 2000, 11(12): 1061-1062.

摘要 ( )

可视化

Gnetuhainin P, a new isorhapontigenin dimer, was isolated from the Lianas of Gnetum hainanense C. Y. Cheng. Its structure was established on the basis of spectroscopic evidence, especially 2D NMR techniques.

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A New Disaccharide from the Fern Macrothelypteris digophlebia

Ming Hua QIU, Jin Ming GAO, Hu Qi LIU, Jian Xi FU

中国化学快报. 2000, 11(12): 1063-1064.

摘要 ( )

可视化

A new disaccharide,digobiose 1, was isolated from the rhizomes of Macrothelypteris digophlebia (Bak.) Ching var. elegans (koidz.). Its structure which is very similar with that of sucrose was identified as α-D-glucopyranosyl (1→2')-β-D-sorbopyranoside by spectroscopic analysis.

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Insignin A, A Novel C₂₁-Steroidal Aglycone from Biondia insignis

Yuan Hu ZHANG, Yue Mao SHEN, Yuan Ying WEN, Ting Yun KUANG

中国化学快报. 2000, 11(12): 1065-1068.

摘要 ( )

可视化

Insignin A, a new C₂₁-steroidal aglycone having the rare 15,16-seco pregnane skeleton was isolated from the acidic hydrolysis part of the 95% EtOH extract of Biondia insignis. It's structure was identified to be 15R,16-epoxy-3β,14β,16β-trihydroxy-15,16-secopregn-5-ene-20-one based on the spectral data.

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Two New Abietane Diterpenoids from Coleus xanthanthus

Shuang Xi MEI, Zhi NA, Xue Mei NIU, Chao Ming LI, Zhong Wen LIN, Han Dong SUN

中国化学快报. 2000, 11(12): 1069-1072.

摘要 ( )

可视化

From the petroleum part of the 70% acetone extract of Coleus xanthanthus, two new abietane diterpenoids have been isolated and identified as 11-acetoxy-coleon U(1) and 11,16-diacetoxy-coleon U(2).Their structures were elucidated with spectral methods.

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Identification and determination of (+)-sesamin in Semen Cuscutae by capillary GC and GC-MS

Yan LI, Min YE, Hu Wei LIU, Xiu Hong JI, Yu Ning YAN

中国化学快报. 2000, 11(12): 1073-1076.

摘要 ( )

可视化

(+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of (+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of (+)-sesamin and GC-MS for its identification. The result suggested that this approach could be used to identify Semen Cuscutae from various sources based on the different content of (+)-sesamin in them.

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Resolution of 3,3'-Dioxo-1,1'(3H,3'H)spirobi[isobenzofuran] -5,6,5'6'-tetracarboxylic acid and Optically active Polyimides thereof

Fu She HAN, Jian Qiang QU, Xin ZHANG, Meng Xian DING, Lian Xun GAO

中国化学快报. 2000, 11(12): 1077-1080.

摘要 ( )

可视化

3,3'-Dioxo-1,1'(3H,3'H)spirobi[isobenzofuran]-5,6,5',6'-tetracarboxylic acid 1 was resolved successfully and the corresponding optically active polyimides PI were synthesized. The properties of the optically active PI and the racemic one were investigated. The results showed that the specific rotation of (-)-PI was about two times to that of the (+)-PI, and the regularity of the optically active PI was higher than that of the racemic one.

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p-Hydrazinobenzenesulfonic Acid Derivatives of Carbohydrates and Their Capillary Zone Electrophoresis

Xiao Yan WANG, Yi CHEN

中国化学快报. 2000, 11(12): 1081-1084.

摘要 ( )

可视化

p-Hydrazinobenzenesulfonic acid is explored as a novel ultraviolet labeling reagent for capillary electrophoresis (CE) of mono-and disaccharides. The labeling reaction takes less than 10 minutes and introduces both of absorption and charge groups into the sugars.

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Characterization of Formation Kinetics of Self-Assembled Thiol Monolayers on Gold by Electrochemical Impedance Spectroscopy

Peng DIAO, Min GUO, Ru Ting TONG

中国化学快报. 2000, 11(12): 1085-1088.

摘要 ( )

可视化

Self-assembled monolayers of octadecanethiol (ODT) on gold have been studied by electrochemical impedance spectroscopy (EIS). The fractional coverage has been examined as a function of immersion time of Au in ODT deposition solution. The fractional coverage exhibits two distinct adsorption steps:an initial rapid step followed by a slow one. The fractional coverage of ODT monolayer increases sharply from zero to more than 99% of its maximum within the first minute. However, it takes a day for the fractional coverage to approach its final value.

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Structural Vector Description and Estimation of Normal Boiling Points for 66 Aromatic Hydrocarbons

Shu Shen LIU, Chun Sheng YIN, Shao Xi CAI, Zhi Liang LI

中国化学快报. 2000, 11(12): 1089-1092.

摘要 ( )

可视化

A molecular vector-type descriptor containing 6 variables is used to describe the structure of aromatic hydrocarbons (AHs) and relate to normal boiling points (bp) of AHs. The correlation coefficient (R) between the estimated bp and experimental bp is 0.9988 and the root mean square error (RMS) is 7.907℃ for 66 AHs. The RMS obtained by cross-validation is 9.131℃, which implies the relationship model having good prediction ability.

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Small Angle X-ray Scattering Study of PS Conformation in Tetrahydrofuran Solvent with Gas Anti-solvent

Dan LI, Zhi Min LIU, Guan Ying YANG, Qing HUO, Bu Xing HAN, Yi LIU, Zhong Hua WU, Bao Zhong DONG

中国化学快报. 2000, 11(12): 1093-1094.

摘要 ( )

可视化

Small angle X-ray scattering (SAXS) was used to study the effect of dissolved CO₂ on the conformation of polystyrene (PS) in PS/tetrahydrofuran(THF) solution at 308.15 K and at pressures up to 3 MPa. The cloud pressure and the expansion curve of the solution were also determined. The dependence of the conformation on pressure was discussed.

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Effect of Spacers on CMCs and Micelle-forming Enthalpies of Gemini Surfactants by Titration Microcalorimetry

Guang Yue BAI, Hai Ke YAN

中国化学快报. 2000, 11(12): 1095-1096.

摘要 ( )

可视化

The critical micelle concentrations (CMC) and the micelle-forming enthalpies (△H_mic) of gemini surfactants were first measured by the precise titration microcalorimetry. The results showed that △H_micvalues are negative, and there is an exothermal minimum between s=4 and s=6. Furthermore, the CMCs of the surfactants are in good agreement with literature values.

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A New Humidity-Sensitive Material Based on PPBT Prepared with Palladium Complex Catalyst

Hong Mei SUN, Mu Jie YANG, Ming Fang LING

中国化学快报. 2000, 11(12): 1097-1100.

摘要 ( )

可视化

Soluble Poly(propargyl benzoate) (PPBT) with π-conjugated structure was synthesized using a novel bis(triphenylphosphine)-bisacetylide palladium complex catalyst[Pd(PPh₃)₂(C≡CCH₂OOCPh)₂] (PPB). An interdigital gold electrode was covered by screen printing films of doped PPBT (DPPBT) to prepare a resistance-type humidity sensor, which exhibits electrical response towards relative humidity (RH%) variations in the range 11%-96%. PPBT shows promise as a new humidity-sensitive material.

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Kinetic Studies on Forming Iso-nuclear β-type Chelates of Rare Earths with p-Sulphoaminobromophosphonazo

Fei ZHA, Li YUAN, Jin Zhang GAO, Hui CHEN

中国化学快报. 2000, 11(12): 1101-1102.

摘要 ( )

可视化

The kinetic behavior of forming the iso-nuclear β-type chelates of rare earth ions (RE³⁺) with p-sulphoaminobromophosphonazo (BPA-pSN) in ClCH₂ COOH-CH₃ COONa buffer solutions were studied by a spectrophotometric method.

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Improved Cellulose Adsorption Method for the Preparation of Perovskite Oxides with Large Specific Surface Area at Low Temperature

Zong Ping SHAO, Guang Tao LI, Guo Xing XIONG, Wei Shen YANG

中国化学快报. 2000, 11(12): 1103-1106.

摘要 ( )

可视化

Perovskite-type La_1-x Sr_x MO_3-δ (x=0,0.1,0.2, B=Co,Fe,Mn) oxides were prepared by pyrolysis of metal salt-(organic acid)-cellulose compound precursors. Low calcination temperatures, usually lower than 600℃, were needed. The specific surface area of the as-prepared oxides is higher than that prepared by the cellulose adsorption method, and is comparable to that prepared by sol-gel method. The effective organic acid could be EDTA acid, citric acid or DL-hydroxysuccinic acid, among them, EDTA acid is the best one.

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Synthesis of Cubic Mesoporous Silica MCM-48 by Mixed Micellar Templates

Tong Wen WANG, Le Rong DAI

中国化学快报. 2000, 11(12): 1107-1110.

摘要 ( )

可视化

High-quality mesoporous silica MCM-48 were synthesized under basic conditions by using the mixture of cetyltrimethylammonium bromide (CTAB) and alkylamine (C_n NH_2n+3, n=8,10,12,14, respectively) as templates. The effects of the alkylamines with different chain lengths (n=8,10,12,14,16,18, respectively) on the silica structure were investigated.

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Valence of elements in HgBa₂Ca_n-1Cu_nO_2n+2+δ(n=1, 2, 3, 4)

Zhi Jian WU, Si Yuan ZHANG

中国化学快报. 2000, 11(12): 1111-1112.

摘要 ( )

可视化

Valence of elements in HgBa₂Ca_n-1Cu_nO_2n+2+δ(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence for the highest Tc sample. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produce more carriers than argon annealed samples.

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2000年, 第11卷, 第12期　刊出日期：2000-12-20

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2000年, 第11卷, 第12期 刊出日期：2000-12-20

2000年, 第11卷, 第12期　刊出日期：2000-12-20