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炔基砜和三丁基锡化氢在四(三苯基膦)钯催化下于苯中室温下进行锡氢化反应4 h,经溶剂转换成DMF后,再在CuI助催化剂存在下与炔基溴化物于室温进行Stille偶联反应,以良好产率且立体选择性地合成了( Z)-2-砜基取代的1,3-烯炔。该“一锅”合成法具有起始原料易得、反应条件温和、操作简便、钯催化剂利用率高和产率好等优势。 相似文献
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(E)-1-氯-6,6-二甲基-2-庚烯-4-炔是合成盐酸特比萘芬的关键中间体,N-氯代二异丙胺/三苯基膦与6,6-二甲基-1-庚烯-4-炔-3-醇反应,可以立体选择性地得到反式的该化合物,其反式/顺式异构体的比例达9/1,为特比萘芬提供了可工业放大生产的立体选择性合成方法。 相似文献
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Wen Yan Hao Jian Wen Jiang Ming Zhong Cai 《中国化学快报》2007,18(7):773-776
(E)-a-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2- sulfonyl-substituted 1,3-enynes 3 in high yields. 相似文献
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以对羟基苯甲酸为原料,首次合成(Z)-3-丁烯基-5-羟基苯酞.发现芳环上的甲胺甲酸基中氮原子的诱导作用是关键步骤,使甲胺甲酸基邻位选择性理化,从而在芳环上定向引入甲酸基. 相似文献
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利用6-(4-卤代苯基)-3(2H)-哒嗪酮的银盐(2)与2,3,4,6-四-O-乙酰基-1-溴-1-脱氧-α-D-吡喃葡萄糖(3)发生Koenigs-knorr反应,
合成了3-O-(2,3,4,6-四-O-乙酰基-β-D-吡喃葡萄糖-1-基)-6-(4-卤代苯基)哒嗪(4),4用干燥的氨气在0℃~-5℃下处理脱乙酰基保护基得相应的3-O-(β-D-吡喃葡萄糖-1-基)-6-(4-卤代苯基)哒嗪(5).其结构经元素分析,IR及1H
NMR证实. 相似文献
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(E)-α-Stannylvinyl phenyl(or p-tolyl)sulfones underwent an iododestannylation reaction to afford (E)-α-iodovinyl phenyl(or p-tolyl)sulfones 1, which reacted with (E)-alkenylzirconium(IV) complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd(PPh3)4 catalyst to afford stereoselectively (1Z,3E)-2- phenyl(or p-tolyl)sulfonyl-substituted 1,3-dienes 3 in good yields. 相似文献
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Hydromagnesiation of silylarylacetylenes 1 in diethyl ether gave(E)-β-silylvinyl Grignard reagents 2,whichreacted with trialkylstannyl chlorides 3 to afford stereoselectively(E)-β-silylvinylstannanes 4 in good yields. 相似文献
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The cross-coupling reaction of trans-alkenylboronic acids with a-bromoacetic esters was firstly studied. It was found that using Pd(OAc)2 as catalyst, a bulky electron-rich phospine, (2-dicyclohexylphospino-biphenyl) as ligand, the reaction can be readily accomplished to give specific (E)-b,g-unsaturated esters in high yields. 相似文献
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IntroductionRecentlymuchattentionhasbeendevotedtothesynthesisofα ,β unsaturatednitrilessincetheyareim portantstructuralfeatureofseveralnaturallyoccurringbi ologicallyactivecompounds .1,2 Theintroductionoffluo rineortrifluoromethylgroupintobiologicallyactiv… 相似文献
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Based on the different reactivity of selanyl and bromo groups,(E)-α-bromovinylselenides can undergo sequential cross coupling reactions with nucleophiles in the presence of transition metal complexes to form two carbon-carbon bonds in the same olefinic carbon leading to trisubstituted alkenes stereoselectively in good yields. 相似文献
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2‐Ethoxycarbonyl‐substituted 1,3‐dienes and 1,3‐enynes can be stereoselectively synthesized in one pot under mild conditions, in good yields, by the palladium‐catalyzed hydrostannylation of alkynyl esters, followed by Stille coupling with alkenyl or alkynyl halides, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Zirconium(IV) chloride catalyzed efficient one-pot synthesis of β-amino/β-acetamido carbonyl compounds at room temperature is described. In the presence of ZrCl4, the three-component Mannich-type reaction via a variety of in situ generated aldimines, with various ketones, aromatic aldehydes and aromatic amines in ethanol, led to the formation of β-amino carbonyl compounds and the four-component Mannich-type reaction of aromatic aldehydes with various ketones, acetonitrile and acetyl chloride resulted in the corresponding β-acetamido carbonyl compounds in high to excellent yields. This methodology has also been applied towards the synthesis of dimeric β-amino/β-acetamido carbonyl compounds. 相似文献
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Based on the different reactivity of stannyl and bromo groups, (Z)-α-bromovinylstannanes can undergo the cross-coupling reaction with alkynyl Grignard reagents in the presence of tetrakis(triphenylphosphine)palladium(0) catalyst in THF at room temperature to afford stereoselectively 1,3-enynylstannanes in good yields. 相似文献
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A new approach to the synthesis of α,β-unsaturated ketones from 1,2,3-trimethyl benzimidazolium salt via the condensation reaction with aldehydes followed by the addition reaction of Grignard reagents with quaternary C=N bond was provided. 相似文献