共查询到20条相似文献,搜索用时 15 毫秒
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微波在有机合成化学中的应用及进展 总被引:27,自引:4,他引:27
简述了微波有机合成的机理和特点,介绍了近年来微波辐射技术在有机合成中的应用,展望了微波促进有机合成化学的发展方向。参考文献30篇。 相似文献
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Satoru Masamune William Choy John S. Petersen Lawrence R. Sita 《Angewandte Chemie (International ed. in English)》1985,24(1):1-30
This account examines double asymmetric induction from theoretical and practical viewpoints. In the context of four major organic reactions-the aldol, Diels-Alder, catalytic hydrogenation, and epoxidation-it is shown that a double asymmetric induction can be analyzed in terms of the single asymmetric reactions of each of the two chiral reactants. A rule which qualitatively relates the results of these single asymmetric reactions with the outcome of the double asymmetric reaction is proposed. A powerful new strategy based on this rule for the predictable creation of new chiral centers is discussed and the use of this strategy for the synthesis of sugars and macrolides is presented. 相似文献
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合成了一种新型的聚合物载体—2-聚苯乙烯磺酰基乙醇,并研究其在固相有机合成中应用,聚苯乙烯亚磺酸钠树脂(1)在相转移催化剂BU4NI和助催化KI的作用下,与氯乙进行砜化反应,得到含羟基功能基的2-聚苯乙烯磺酰基乙醇树脂2。树脂2用Boc保护的氨基酯化,封闭树脂上未反应的羟基,用酸脱保护并用三乙胺中和,再与异(硫)氰酸苯酯反应生成聚合生物支载的脲树脂6树脂6用酸解脱得到海因和硫代海因化合物,用碱处理树脂6是得到取代的脲和硫脲,优化了合成反应的全过程,探讨了树脂在酸性和碱性条件下的解脱方法,结果表明,2-聚苯乙烯磺酰基乙醇树脂易与羧基形成含酯键的连接桥,连接桥在强酸性和碱性条件下均可解脱得到产物。 相似文献
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为了寻找活性更好的抗真菌化合物,基于已有的计算机辅助药物设计结果,保留氟康唑母体结构必需药效团,设计、合成了22个含对甲酚和胸腺嘧啶的氟康唑新衍生物.目标化合物的结构经1H NMR、元素分析和ESI-MS确证,初步体外抗真菌活性试验结果表明,化合物5l对7种真菌都表现出了较好的抗真菌活性(烟曲霉菌除外),化合物5a~5e,5g,5h,7a和7b对不同真菌表现出了一定的抗真菌活性.炔丙基取代氨基侧链结构的引入有利于提高该类目标化合物体外抗真菌活性,值得进一步深入研究. 相似文献
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Several studies have used microwaves as a heat source for carrying out various types of reactions employing circulation reaction vessels. The microwave flow chemical synthesis methodology is most appropriate in the use of microwaves in chemical syntheses. It can attenuate the problem of microwave heating (non‐uniform heating and penetration depth) and maximize the benefits (rapid heating and first temperature adjustments). In this brief review, we examine and explain some of the relevant features of microwave heating with applicative examples of the usage of microwave flow chemistry equipment in carrying out organic syntheses, enzymatic reactions, and (not least) nanoparticle syntheses. 相似文献
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Zhi LIU Qi FANG* Wen Tao YU Guo Qun LIU Wen XU Min Hua JIANG Bin ZHANG Dao Ben ZHU State Key Laboratory of Crystal Materials Shandong University Jinan Institute of Chemistry The Chinese Academy of Science Beijing 《中国化学快报》2002,13(8)
Having more than twenty years?glory, ET series still keep the most promising family in various kinds of organic conductors. Most of ET based molecular conductors consist of organic cationic ET+0.5 radical and certain anionic inorganic component such as the superconductor k-(ET)2Cu[N(CN)2]Cl (TC = 12.8K, 0.3kbar)1. Recently, the first purely organic superconductor b-(ET)2SF5CH2CF2SO3 (TC = 5.2K)2 has been reported, which aroused our interest on this kind of inorganic-free organic c… 相似文献
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Wolfgang Oppolzer 《Angewandte Chemie (International ed. in English)》1984,23(11):876-889
Rapidly accumulating evidence shows the value of asymmetric Diels-Alder and ene reactions for the syntheses of enantiomerically pure molecules. This article presents a systematic and critical treatment of various stereoface-differentiating principles, including very recent spectacular advances. The chiral information is mainly provided by covalently bound auxiliaries, some of which are crystalline, inexpensive, and readily available from naturally occurring monoterpenes, hydroxy acids, amino acids, steroids, and sugars. Non-destructive transfer of chirality leads to the efficient creation of up to four chiral centers with predictable relative and absolute configurations. Regenerative cleavage of the auxilary group from the diastereomerically pure adducts furnishes a range of polyfunctional, optically pure building blocks. Their synthetic potential is illustrated by strategic applications to the syntheses of physiologically interesting, chiral natural products such as prostaglandins, antibiotics, terpenoids, shikimic acid, alkaloids, and kainoids. 相似文献
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介绍近几年来二氯二茂钛 (锆 ) /格氏试剂体系在有机合成中的应用 ,特别是使用该体系发展的新反应及其机理的研究情况 相似文献
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Dr. Rupam Sen Debraj Saha Dr. Subratanath Koner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(19):5979-5986
The role of pH in the formation of metal–organic frameworks (MOFs) has been studied for a series of magnesium‐based carboxylate framework systems. Our investigations have revealed the formation of five different zero‐dimensional (0D) to three‐dimensional (3D) ordered frameworks from the same reaction mixture, merely by varying the pH of the medium. The compounds were synthesized by the hydrothermal method and characterized by single‐crystal X‐ray diffraction. Increase of the pH of the medium led to abstraction of the imine hydrogen from the ligand and a concomitant increase in the OH? ion concentration in the solution, facilitating the construction of higher dimensional framework compounds. A stepwise increase in pH resulted in a stepwise increase in the dimensionality of the network, ultimately leading to the formation of a 3D porous solid. A gas adsorption study of the 3D framework compound confirmed its microporosity with a BET surface area of approximately 450 m2 g?1. Notably, the 3D framework compound catalyzes aldol condensation reactions of various aromatic aldehydes with acetone under heterogeneous conditions. 相似文献
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Péter Bakó Tibor Bakó Katalin Bisztray Áron Szöllősy Kornél Nagy László Tőke 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):247-251
New chiral monoaza-15-crown-5 ethers have been synthesised from 1,2:5,6-di-O-isopropylidene-D-mannitol. The substituent at the nitrogen atom has a major influence on the cation extraction ability of the azacrown. These sugar-based crown ethers show asymmetric induction as chiral phase transfer catalysts in the Michael addition of 2-nitropropane to chalcone (67% ee). 相似文献