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Chiral Salen Manganese Complex Immobilized on SBA-15:A New Heterogenized Enantioselective Catalyst forthe Epoxidation of Alkenes

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Chinese Chemical Letters 2004年第6期15卷 655-658页

作者： XinMeiZHENG YanXingQI XiaoMingZHANG JiShuanSUO lanzhouinstituteofchemicalphysics ChineseAcademyofSciencesLanzhou730000

Jacobsen's catalyst was immobilized onto SBA-15 by multi-step grafting, and this heterogenized catalyst exhibited comparable catalytic performance with the corresponding homogeneous counterpart for the epoxidation of ... 详细信息

关键词： SBA-15 chiral salen Mn(Ⅲ) complex alkenes asymmetric epoxidation.

A Selective Colorimetric Anion Sensor Based on Di(hydroxymethyl) Di-(2-pyrrolyl)methane-TCBQ System

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Chinese Chemical Letters 2004年第9期15卷 1117-1119页

作者： YongGUO ShiJunSHAO JianXU YanPinSHI ShengXiangJIANG lanzhouinstituteofchemicalphysics ChineseAcademyofSciencesLanzhou730000

A new class of non-covalent charge-transfer complex for anion sensing, consisting of di(hydroxymethyl) di-(2-pyrrolyl) methane and chloranil (TCBQ) is characterized. The new colorimetric anion sensors can generate visual color change against PO43- and HPO42- anions in EtOH/H2O (1:1 v/v) mixture solution. The dipyrromethane-quinone aggregations may be used for higher selective detection of PO43- than other inorganic anions in water solution.

关键词： Dipyrromethane charge-transfer complex anion detection sensor.

Preparation of A New Fiber by Sol-gel Technology in Solid-phase Microextraction (SPME)

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Chinese Chemical Letters 2004年第9期15卷 1127-1130页

作者： LiMingWEI QingYuOU JuBaiLI lanzhouinstituteofchemicalphysics ChineseAcademyofSciencesLanzhou730000

The sol-gel technology is applied for the preparation of solid-phase microextraction (SPME) fiber. The fiber demonstrates high thermal stability, efficient extraction rate and the selectivity for non-polar or low-polar analytes. Efficient SPME-GC-FID analyses of benzene- toluene-ethylbenzene-xylenes (BTEXs) and low-polar halocarbon were achieved by the sol-gel coated DSDA-DDBT-TiO2 fiber. Some parameters of the SPME fiber for the determination of halocarbon in aqueous sample were investigated.

关键词： Solid-phase microextraction sol-gel technology selectivity polyimide (DSDA-DDBT).

Surface Confined Ionic Liquid——A New Stationary Phase for the Separation of Ephedrines in High-performance Liquid Chromatography

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Chinese Chemical Letters 2004年第9期15卷 1060-1062页

作者： ShuJuanLIU FengZHOU XiaoHuaXIAO LiangZHAO XiaLIU ShengXiangJIANG lanzhouinstituteofchemicalphysics ChineseAcademyofSciencesLanzhou730000

In this article, a new and effective stationary phase based on ionic liquid modified silica is first reported and used for the separation of ephedrines in high-performance liquid chromatography (HPLC). The separation results indicate the high efficiency and reproducibility of the stationary phase. The electrostatic interaction, ion-exchange interaction between the solutes and the stationary phase are considered to attribute the effective separation. Moreover, the free silanols on the surface of the silica are effectively masked by the immobilized ionic liquid, a result of which is to decrease the non-specific absorption.

关键词： Ionic liquid ephedrines HPLC.

Two Novel Epimeric Eremophilane Sesquiterpenes from the Flower of Cacalia tangutica

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Chinese Chemical Letters 2005年第6期16卷 774-776页

作者： XiaLIU YanPingSHI KeyLaboratoryforNaturalMedicineofGansuProvince LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000

Two novel epimeric eremophilane sesquiterpenes, 7β-H-3α-angeloyl-9(10)-ene-11, 12-epoxy-8-oxoeremophilane (1) and 7β-H-3α-angeloyl-9(10)-ene-11, 12-epoxy-8-oxoeremophi- lane (2) were isolated from the methanol extract of the flower of Cacalia tangutica (Franch.) Hand-Mazz. Their structures were characterized by 1D-, 2D-NMR (1H-1H COSY, HMQC, HMBC, 1H-1H NOESY) and HRESI-MS techniques.

关键词： Cacalia tangutica Compositae eremophilane sesquiterpene.

A Mild and Efficient Oxidation of Alcohols in Water

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Chinese Chemical Letters 2004年第10期15卷 1149-1152页

作者： ChuanZhiXU LinCHEN ZhenLI WeiSUN ChunGuXIA StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000

A mild and efficient oxidation of alcohols to the corresponding carbonyl compounds using the PhI(OAc)2 (1.1 eq.) with n-Bu4NBr (8 mol %) in water at room temperature is described. This new procedure is very simple and... 详细信息

关键词： Oxidation alcohols n-Bu4NBr PhI(OAc)2 water.

A Novel Terpenoid from Lappula anocarpa

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Chinese Chemical Letters 2004年第6期15卷 664-666页

作者： YuanPengJIN YanPingSHI KeyLaboratoryforNaturalMedicineofGansuProvince LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000

A novel terpenoid, named lappulanocarpine A1 was isolated from the alcoholic extract of the whole plant of Lappula anocarpa. Its structure was characterized by ID-, 2D-NMR and HR-ESIMS.

关键词： Lappula anocarpa Boraginaceae terpenoid lappulanocarpine A.

Synthesis and Characterization of the Chiral Skeleton Cluster [NiRuMo(CO)_5(μ_3-S)(η~5-C_5H_5)(η~5-C_5H_4COCH_3)]

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Chinese Journal of Structural Chemistry 2002年第5期21卷 489-492页

作者：边治国孙杰等 StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsTheChineseAcademyofSciencesLanzhou730000China ShanghaiInstituteofOrganicChemistry TheC

The new chiral cluster [NiRuMo(CO)5(m3-S)(h5-C5H5)(h5-C5H4COCH3)] 3 was synthesized by the reaction of precursor [CoRuMo(CO)8(m3-S)(h5-C5H4COCH3)] 1 with NiCp2 2 in refluxing THF. It was characterized by C/H elemental analysis, IR and 1H NMR. Molecular structure of cluster 3 was determined by single-crystal X-ray analyses. Crystal data: triclinic, space group P with the following crystallographic parameters: a = 7.9606(8), b = 8.5604(9), c = 14.779(2) , a = 93.908(2), b = 105.057(2), g = 101.463(2)? C17H12O6MoNiRuS, Mr = 600.05, Z = 2, V = 945.5(2) 3, Dc = 2.108 g/cm3, m = 2.568 mm-1, (2q )max ≤ 56.48, F(000) = 584,the final R = 0.0380 and wR = 0.0674 for 2995 observed reflections with I > 2.00s(I).

关键词： transition metal chiral cluster crystal structure

An Efficient Synthesis of 2-Oxazolidinones by Palladium-catalyzed Oxidative Carbonylation of β-Aminoalcohols and 2-Aminophenol under Mild Conditions

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Chinese Journal of Chemistry 2005年第5期23卷 643-645页

作者：李福伟彭新高夏春谷胡斌 StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesandGraduateSchooloftheChineseAcademyofSciencesLanzhouGansu73000China

Oxidative carbonylation of β‐aminoalcohols and 2‐aminophenol in Pd(OAc) 2 /I 2 catalytic system to produce the corresponding 2‐oxazolidinones was conducted with high yields and selectivities in short reaction time. Mild reaction conditions, high catalytic turnover frequency value, improved yields and selectivities are the remarkable features exhibited by this process.

关键词： oxidative carbonylation β‐aminoalcohol 2‐aminophenol 2‐oxazolidinone catalytic turnover frequency