中国化学快报

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A Facile Synthesis of 0,0-Dialkyl-α-(PhenylCarbamyloxy) Alkyl Phosphonates

Hong Wu HE, Si Quan WANG, Wei Bin CHEN, Zhao Jie LIU

中国化学快报. 1998, 9(05): 415-416.

摘要 ( )

可视化

A series of title compounds were synthesized by the addition reaction of dialkyl-α-hydroxyphosphonates and phenyl isocyanate under base catalysis. All new compounds have been identified by ¹H NMR, ³¹P NMR, IR and elemental analysis.

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Samarium Diiodide-Mediated Reductive Cleavage of Se-Se Bond ofDiacyl Diselenides:A New Method for Synthesis of β-Selenoesters

Yong Min ZHANG, Wen Ying HAO, You HUANG, Jia Jun ZHU

中国化学快报. 1998, 9(05): 417-420.

摘要 ( )

可视化

The reduction of diacyl diselenides by samarium diiodide led to the production of samarium acylselenolates, which reacted with α,β-unsaturated esters or nitriles to give β-selenoesters or selenonitriles under mild and neutral conditions.

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The Chloromethylation Reaction of Substituted Titanocenes( η⁵-C₅H₅)( η⁵-C₅H₄CRR'C₆H₄X)TiCl₂

Zheng Jie HE, You Ming WANG, Shou Shan CHEN

中国化学快报. 1998, 9(05): 421-422.

摘要 ( )

可视化

The chloromethylation reaction of substituted titanocenes (η₅-C₅H₅)(η⁵-C₅H₄CRR' C₆H₄X)TiCl₂ 1 in the presence of polyformaldehyde and dry hydrogen chloride is reported.

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Photoassisted Methoxycarbonylation of Straight-Chain TerminalOlefins under Ambient Conditions

Da Bin GAO, Ming GUO, Xiao Hui ZHANG, Jing Mei YIN, Yong An MA

中国化学快报. 1998, 9(05): 423-425.

摘要 ( )

可视化

Methoxycarbonylation was performed on 1-heptene, 1-octene and 1-dodecene with Co(acac)₂ catalyst in the presence of UV light under ambient conditions.

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Arylation of Allylic Alcohols with Aryl Iodides Catalyzed by a Silica-Bound Bidentate Sulfur Palladium (0) Complex

Ming Zhong CAI, Xian HUANG, Cai Sheng SONG

中国化学快报. 1998, 9(05): 427-430.

摘要 ( )

可视化

Allylic alcohols react with aryl iodides in the presence of tri-n-butylamine and a catalytic amount of a silica-bound bidentate sulfur palladium (0) complex to form 3-arylaldehydes or ketones in good yields.

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The Synthesis of an Optically Active Intermediate of A-Ring for1α,25-Dihydroxy Vitamin D3 Analogs

Yong WU, Mei GUAN

中国化学快报. 1998, 9(05): 431-432.

摘要 ( )

可视化

Synthesis of an optically active intermediate 4b for the A-ring of 1α,25-dihydroxyvitamin D₃ analogs has been achieved in eight steps, starting from readily available, inexpensive D-(+)-xylose.

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Total Synthesis of (±)-Calanolide A and Its Anti-HIV Activity

Chun Mei ZHOU, Lin WANG, Ming Long ZHANG, Zhi Zhong ZHAO, Xing Quan ZHANG, Xiang Hong CHEN, Hong Shan CHEN

中国化学快报. 1998, 9(05): 433-434.

摘要 ( )

可视化

Anti-HIV agent (±)-calanolide A has been synthesized by a four-step approach starting from phloroglucinol, including the Pechmann reaction, Friedel-Crafts acylation, cyclization, chromenylation and Luche reduction.

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Studies on Carbohydrates XXⅧ. Synthesis of Key Intermediates ofOligosaccharides Related to Serratia marcescens O10 Antigen

Ke Qin ZHANG, Jian Min MAO, Hong Min CHEN, Meng Shen CAI

中国化学快报. 1998, 9(05): 435-437.

摘要 ( )

可视化

In the continuation of our study on the Serratia marcescens O-antigen, two disaccharides 8 and 13, corresponding to the key intermediates of oligosaccharides related to the S. marcescens O10 antigen, were synthesized by the trichloroacetate method. Their structures and compositions were characterized by ¹H NMR, ¹³C NMR, 2D NMR and IR, FAB-MS spcctra.

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Synthesis of Bis(4'-hydroxyphenyl)-toluene-2, 4-diurethane for Main Chain Liquid Crystalline Poly(urethane-ester)s

Yan Qing LIAN, Ming Qi LI, Qi Xiang ZHOU, De Shan LIU

中国化学快报. 1998, 9(05): 439-442.

摘要 ( )

可视化

A new methodology was advanced that mesogenic cores appeared after the formation of urethane groups and during the monomer-to-polymer transition. A new diphenol monomer, bis(4'-hydroxy-phenyl)-toluene-2,4-diurethane (BHPTU), was obtained by the reaction of 2,4-tolulene diisocyanate with hydroquinone in dioxane or N,N-dimethyl-acetamide. The reaction process was monitored by FTIR, and the product was investigated by ¹HNMR and elemental analysis (EA). A liquid crystalline poly(urethane-ester) was obtained using the BHPTU monomer.

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Synthesis of L-Aspartic Acid and Lactone Copolymers

Ren Xi ZHUO, Jie CHENG

中国化学快报. 1998, 9(05): 443-445.

摘要 ( )

可视化

Biodegradable poly(Glc-alt-Asp) was synthesized by ring-opening polymerization of the monomer 3-(S)-[(benzyloxycarbonyl)methyl]-morpholine-2,5-dione and subsequent catalytic hydrogenation. Copolymers of the monomer with glycolide, D,L-lactide and L-lactide were also prepared.

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Synthesis of Polynorbornene-Poly (ethylene-co-propylene)Diblock Copolymer

Qing WU, Qing WEN, Ze Jian LU

中国化学快报. 1998, 9(05): 447-450.

摘要 ( )

可视化

Transformation of living ring-opening metathesis polymerization into coordination polymerization by converting the titanacyclobutane group attached to a polynorbomene chain into titanocene alkoxide has been used for the synthesis of polynorbornene-poly(ethylene-co-propylene) block copolymer. Preliminary characterizations of the copolymerization products by solvent extraction and ¹³C NMR spectrum are reported.

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Synthesis on Multifunctional Groups and MultibranchedCompounds Ⅷ. Synthesis of Dendritic Polyestrone

Jian CHEN, Ling Ling WENG, Hu ZHENG

中国化学快报. 1998, 9(05): 451-453.

摘要 ( )

可视化

In this article, using the four-directional core and quaternary carbon branching point, a dendritic polyestrone with twelve estrone units was synthesized by convergent strategy. Its structure was confirmed by IR and NMR spectra.

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Bioisostere of Sulfonyl Moiety-The Synthesis of New ALS Inhibitors N-(Asymmetry Disubstituted Phosphoryl)-N'-(4,6-dimethoxypyrimidin-2-yl) Ureas

Guo Feng ZHAO, Hua Zheng YANG, Yong Hong LI

中国化学快报. 1998, 9(05): 455-458.

摘要 ( )

可视化

In view of the isosterism of the sulfonyl (-S0₂-) and phosphoryl groups [-P(0)(0R)-, R=H, CH₃, C₂H₅, etc], two new types of ureas, N-(N-aryl-O-alkyl phosphoryl)-N'-(4, 6-dimethoxy pyrimidin-2-yl) ureas 2 and N-(N-aryI-N-alkyl phosphoryl)-N'-(4, 6-dimethoxy pyrimidin-2-yl) ureas 3,were synthesized by treating N-(arylaminochlorophosphoryl)-N'-(4,6-dimethoxy pyrimidinyl-2-) ureas 4 with alcohols or amines. Compounds 4 were obtained by reacting dichlorophosphoryl isocyanate with 4,6-dimethoxy-2-aminopyrimidine, and then with aromatic amines. The enzyme tests (in vitro) indicated that compounds 2 and 3 were two novel classes of acetolactate synthase (ALS) inhibitors, which showed that the phosphoryl group, [-P(0)(0R)-], or[-P(0)(NHR)-], was a good bioisostere of the sulfonyl group (-S0₂-) in sulfonylurea.

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Ab Initio Study of the Excited State Decomposition Reactions ofMonothioformic Acid

Xiao Guang XIE, Huai CAO, Xian Jun BI, Shu Shan DAI

中国化学快报. 1998, 9(05): 459-461.

摘要 ( )

可视化

The possible excited state decomposition reactions (dehydrogensulfidation, dehydration, and dehydrogenation) of the four tautomers of monothioformic acid have been investigated by ab initio methods with 6-31G^** basis sets at the CIS level. The activation energies of the four excited state reactions are 42.57,42.49,56.90,47.73 kcal/mol, and are respectively lower than that of the ground states by 24.52,24.98, 27.28,and 21.10 kcal/mol.

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A Study on the Driving Force for Binding of Benzene Derivatives by α-and β-Cyclodextrin

Shuang Hui LUO, Hui Ming JMNG, You Cheng LIU, Qing Xiang GUO

中国化学快报. 1998, 9(05): 463-464.

摘要 ( )

可视化

A three-dimensional diagram shows that the association constants (K_a) for the inclusion of a- and β-CD with substituted benzene are mainly correlated with the molar refraction (R_m) and hydrophobic constant (π_x)of the substituents of guest compounds. It reveals that the inclusion of cyclodextrin with the substituted benzene is dominantly driven by van der Waals forces and hydrophobic interactions.

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Grayanane Diterpenoids from Pieris formosa

Li Quan WANG, Bing Yang DING, Wei Min ZHAO, Guo Wei QIN

中国化学快报. 1998, 9(05): 465-467.

摘要 ( )

可视化

Three grayanane diterpenoids 1-3 were isolated from Pieris formosa. 1 was identified as a new natural product and 2 and 3 as known grayanoside C and grayanotoxin ⅹⅧ on the basis of spectral analysis.

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New Phloroglucinol Glycosides from Hypericum japonicum

Qing Li WU, Sheng Ping WANG, Li Wei WANG, Jun Shan YANG, Pei Gen XIAO

中国化学快报. 1998, 9(05): 469-470.

摘要 ( )

可视化

Two new phloroglucinol glycosides, 2,6-dihydroxy-3,5-dimethyl-l-isobutyrylbenzene-4-0-β-D-glucoside and 2,6-dihydroxy-3,5-dimethyl-l-(2-methylbutyryl) benzene-4-O-β-D-glucoside were isolated from Hypericum japonicum. Their structures were determined by spectroscopic and chemical methods.

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Flow-injection Chemiluminescence Sensor for Hydrogen Peroxidewith Immobilized Reagents

Bao Xin LI, Wei QIN, Zhu Jun ZHANG

中国化学快报. 1998, 9(05): 471-472.

摘要 ( )

可视化

A novel chemiluminescence (CL) sensor for H₂0₂ combined with flow injection analysis is described in this paper. H₂0₂ is sensed by the CL reaction with luminol and Co²⁺ bleeding from the ion exchange column with immobilized reagents by hydrolysis. The calibration graph is linear and falls between the range of 4×l0^-8 to 1×10^-5 mol/L. A complete analysis could be performed in 1 min. The system was reused for over 50 hours.

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The Effect of Cd on the Electrochromic Properties of NiO_xH_y film

Xiao Yan CAO, Wan Lin ZHANG, Guang Yin ZHANG, Wen Hu ZHANG, Yin Nong LIN, Hua Tang YUAN, Zuo Xiang ZHOU, Yun Shi ZHANG

中国化学快报. 1998, 9(05): 473-476.

摘要 ( )

可视化

The effects of 2.8% Cd on the electrochromic properties of NiO_xH_y film were studied. The film was electrodeposited on both the polished Ni plate and conductive ITO glass to study its electrochemical and optical characteristics respectively. It was found that Cd could decrease the working voltage and increase the oxygen evolution voltage as well as the transmittance difference of colored and bleached states of the film. However, it has little effect on the kinetic process.

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A New Model for Calculation of Standard Entropies of Solid Compounds Ⅳ-Calculation of Standard Entropiesof Solid Complex Silicates S

Xun Min YU

中国化学快报. 1998, 9(05): 477-479.

摘要 ( )

可视化

This paper presents a new model for the calculation of the standard entropies of solid complex silicates as follows.S^O₂₉₈=53.630Φ₁+9.91Φ₂-72.81 J/kmol (R=0.9915, Sd:5.39) Sixty complex silicates have been investigated,and good agreement was found between the estimated and experimental entropy values.

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A New Tetranuclear Copper(Ⅰ) Complex of Dithiolate LigandFused with TTF Moiety

Jie DAI, Guo Qing BIAN, Megumu MUNAKATA, Yasuhiro OHNO, Yusaku SUENAGA

中国化学快报. 1998, 9(05): 481-482.

摘要 ( )

可视化

A tetranuclear copper (Ⅰ) complex of the ditholate ligand fused with a TTF moiety has been synthesized and characterized crystallographically. This is the first example of a metal cluster coordinated with the new type ligand. The complex shows interesting redox and radical properties.

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Structure of Complex [Ni₂L₂]( py)₂( H₂O)₂( L=1,3-Di[o-( o-vanillideneimino) phenoxo]-2-propanol Dianion ) with NewNucleating Ligand

Wen Xing ZHANG, Shang Ying LIU, Chang Qin MA, De Hua JLANG

中国化学快报. 1998, 9(05): 483-485.

摘要 ( )

可视化

The title dinuclear complex structure was determined by X-ray diffraction.

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Synthesis of Si- and Ti-MCM-41 Mesostructures via a Novel S⁺X^-I⁺Assembly

Zhao Rong ZHANQ, Ji Shuan SUO, Xiao Ming ZHANG, Shu Ben LI

中国化学快报. 1998, 9(05): 487-490.

摘要 ( )

可视化

Well-defined Si- and Ti-MCM-41 mesoporous molecular sieves were synthesized in high yields through the halogen anion mediated S⁺X^-I⁺ assembly in the presence of cetylpyridinium bromide as template. The spectroscopy characterization of the as-synthesized samples confirmed that Ti (Ⅳ) could be isolated in the lattice positions of the MCM-41 mesostructure by this method.

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Synthesis and Moessbauer Spectra of Four-Coordinated TinCompounds Containing Tin-Copper Bonds

Jin Shan LI, Jing, Kun ZANG

中国化学快报. 1998, 9(05): 491-494.

摘要 ( )

可视化

Seven compounds containing tin-copper bonds, namely [Ph₂P(CH₂)_nPPh₂](CuSnPh₃)₂(n=1-4) and (Ph₂PR)CuSnPh₃ (R=Ph, Bu, Am), have been synthesized. Tin-119 Moessbauer spectra for these compounds were determined. The results have shown that the QS values for these compounds are all zero, the IS values are between 1.32 and 1.38mm/s, and the oxidation state of tin is +4.

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Heat Capacity of Sodium Ditungstate Na₂W₂O₇( s)

Shi Jun LIU, Qi Yuan CHEN, Ping Min ZHANG

中国化学快报. 1998, 9(05): 495-496.

摘要 ( )

可视化

The heat capacity of Na₂W₂O₇(s) has been measured using the drop calorimetry method with a high temperature calorimeter HT1000 in the temperature range of 273-974K. The results can be represented by the equation C_p⁰/J K^-1 mol¹=229.50+8.5052×l0^-2T-3.83373×l0⁶T^-2.

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X-ray Crystal Structure of a Mononuclear Copper (Ⅱ) Complex withUnusual Monodentate O-coordination of Carboxylate Group ofIsonicotinate

Feng Mei NIE, Yan Mei LI, Yu Fen ZHAO, Zhe Ming WANG, Chun Hua YAN

中国化学快报. 1998, 9(05): 497-499.

摘要 ( )

可视化

Reaction of Cu(C10₄)₂·6H₂0 with tripodal ligand tris(2-benzimidazolylmethyl) amine (ntb) and sodium isonicotinate (Iso) yielded a mononuclear complex [Cu(ntb)(Iso)]C10₄·3.5H₂0. The structure has been established by X-ray crystallography. The Cu (·Ⅱ) atom is in a distorted trigonal bipyramidal environment with three benzimidazole N atoms of ntb defining the equatorial plane, one amine N atom of ntb, and one O atom of the carboxylate group of isonicotinate occupying the axial positions.

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Some Unusual Features of Highly Oriented Pyrolytic Graphiteobserved by Electrochemical Scanning Tunneling Microscopy

Bai Lin ZHANG, Yu Fan HE, Er Kang WANG

中国化学快报. 1998, 9(05): 501-504.

摘要 ( )

可视化

Highly oriented pyrolytic graphite (HOPG) is the substrate often used in scanning tunneling microscopy (STM). It is well known that STM images of the basal plane of HOPG show some unusual structural patterns. In this letter, we present in situ STM images of some unusual features on HOPG in solutions, including normal or abnormal chain-like features and hexagonal or oblique superperiodic structures. These features emerge both next to and apart from the step of HOPG.

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Preparation and Characterization of Molybdotungstoniobogermanic Acid

Sheng Xian XU, Guo Qiang HU, Qing Yin WU, Yu Lin SONG

中国化学快报. 1998, 9(05): 505-508.

摘要 ( )

可视化

A new heteropoly complex has been prepared and characterized by chemical analysis, IR spectrum, UV spectrum, X-ray powder diffraction and thermal analysis.

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本期目录

1998年, 第9卷, 第05期　刊出日期：1998-05-20

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本期目录

1998年, 第9卷, 第05期 刊出日期：1998-05-20

1998年, 第9卷, 第05期　刊出日期：1998-05-20