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901.
Qian Yong XU Tong Xing WU Xin Fu PAN* Department of Chemistry National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2001,(12)
Although the asymmetric additions of diethylzinc to aldehydes have been extensively studied in the presence of chiral catalyst, most of the chiral ligands tested are b-amino alcohols1. In this report, the synthesis of chiral gamino alcohols 1-4 from the reaction of (+)-camphor and (-)-menthone with 2-lithiomethyl-6-methyl-pyridine or 2-picolly- lithium2, which give a single diasteromer as determined by 1H NMR with high yields (Scheme 1)3, and their application in the enantioselective additio… 相似文献
902.
Yu Liang ZHANG Ming Xing QIAN Ren HE* State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 《中国化学快报》2001,(12)
Transition-metal-catalyzed oligomerzation of ethylene is an important process to provide a-olefins in the C6~C20 range. In recent years, the catalytic behavior of late transition metal complexes containing bi- and tri-dentate ligands for oligomerization of ethylene to a-olefins has attracted much attention. When oligomerization of ethylene catalyzed by nickel diimine and Fe(II), Co(II) 2,6-bis(imino)pyridine catalysts, the oligomers with high average molecular weight were obtained1-5. Eth… 相似文献
903.
Photodynamic therapy (PDT), using red light and photosensitizers (Sens ), is a promising new treatment for tumor. The naturally occurred hypocrellins,including hypocrellin A (HA) and hypocrellin B (HB,1), have been proposed as the potential photosensitizers for PDT. It has been the subject of many investigations to improve the red absorption and water-solubility of natural hypocrellins by the structural modifications1~3. In this paper, a new derivative 2 was synthesized from 1 and charact… 相似文献
904.
Xuan MAO Yuan Qi YIN Yuan Ming ZHANG Shao Hong PENG Bang Ke ZHONG* State Key Laboratory of Oxo Synthesis Selective Oxidation Lanzhou Institute of Chemical Physics The Chinese Academy of Sciences Lanzhou Department of Chemistry J 《中国化学快报》2001,(2)
Selective oxidation is an important unit process in petrochemistry and fine chemical industry. As a thermodynamically profitable reaction, selective oxidation of hydro- carbons usually takes place with a lot of side-reactions and a great deal of reaction heat at high temperature. To prevent the side-reactions and accelerate heat exchanges are two principal aims in catalytic oxidation1. Using the catalytic film not only can remove the target products from the reaction area in time, but also avo… 相似文献
905.
Wei Min WANG Xin Miao LIANG* Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 《中国化学快报》2001,(2)
Agricultural chemicals such as pesticides were extensively applied in the fields. Pesticides effectively protect the crops, only as long as they remain in the root zone of soil. In case a portion of the chemicals leaves root zone and especially leaches through soil pores. They may pollute groundwater and be a serious environmental problem1. This problem has got widespread concern in the world. In soils the fate of organic compounds such as pesticides is governed by hydraulic transport coupled… 相似文献
906.
Yan WANG Hong Fang SUN Hai Fang WANG Yuan Fang LIU* Department of Technical Physics Peking University Beijing 《中国化学快报》2001,(5)
Nicotine, 3-(1-methyl-2-pyrrolidinyl)pyridine, the main alkaloid in tobacco products, has been well known for its addiction effect. Habitual smokers are usually maintaining nicotine concentration constant in their blood at about 10-15 ng/mL1. Therefore the interaction of nicotine and hemoglobin (Hb) is essential to be studied. Our recent study by accelerator mass spectrometry (AMS) has shown that nicotine could form adducts with Hb after in vivo administration, and there is a positive dose r… 相似文献
907.
908.
Hong Yun GUO Yun Fa ZHENG Yong Min ZHANG * Department of Chemistry Zhejiang University at Xixi Campus Hangzhou Department of Chemistry Zhejiang Normal University Jinhua Department of Chemistry Lishui Teachers College Zhejiang 《中国化学快报》2001,(5)
Selenium is an essential element in living organism. It is reported that the selenosulfides have been transported in vivo in glutathione or coenzyme-A1. It is also discovered in low concentration in garlic2. In organic synthesis, selenosulfides are useful intermediates3. Several methods for the formation of sulfur-selenium bond have been reported. For example, the compounds including S-Se bond were prepared by chloroamination of thiols and selenols4; by heating the selenocyanate with thiols5… 相似文献
909.
Preparation and Properties of Oxidized Graphite Anode Doped with Metal Ion for Lithium Ion Batteries
Yu Quan ZOU Qin Min PAN Ling Zhi WANG Shi Bi FANG* Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2001,(8)
During the past years, there have been a lot of interests in the research of carbonaceous material as anode in lithium ion batteries1-3. Among them, natural graphite seems to be the most promising candidate for anode in lithium-ion batteries in terms of economy. Figure 1 The effect of Different Contents Figure 2 The Effect of Reacting Timeof Mixed Acid on Interlayer Distance On Interlayer DistanceHowever the raw natural graphite cannot be used for commercial purposes, because during proc… 相似文献
910.
Jian Chao YUAN Yu Hua ZHANG Shi Jie LU* State Key Laboratory for Oxo Synthesis Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 《中国化学快报》2001,(6)
Alternating copolymerization of (-olefins with carbon monoxide (CO) catalyzed by cationic palladium-chiral ligand complexes is of great interest due to the potential use of the resulting polymer as a new material1. Recently, enantioselective alternating copolymerization of CO with styrene has been reported by us using PdCl_2-CuCl2-chiral phosphine catalyst2. Here, we first report enantioselective alternating copolymerization of CO with propylene (P) using [(DDPPI)Pd(CH3CN)4](BF4)2 as … 相似文献