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无碱条件下,二甲基亚砜(DMSO)为溶剂,利用氧化亚铜在空气气氛中催化端基炔偶联,高效合成1,3-丁二炔类化合物,并研究了其反应机理.另外,该体系可放大至克级规模反应,且催化剂氧化亚铜可以回收利用. 相似文献
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《有机化学》2016,(8)
以端基炔、二氯甲烷以及有机胺为原料,以废弃螃蟹壳粉负载Cu I制备的CSPs-Cu I为催化剂,高效、绿色合成炔丙胺类化合物.以螃蟹壳粉为载体负载Cu I不仅解决环境污染、资源浪费等问题,也实现了炔丙胺类化合物高效、绿色合成.催化剂通过傅里叶变换红外光谱(FT-IR)、X射线衍射分析(XRD)、热重分析法(TG)以及原子吸收光谱法(AAS)等进行表征分析.通过考察催化剂载体种类、碱等因素对反应的影响,获得最优的反应条件,制得一系列炔丙胺类化合物.研究结果表明,CSPs-Cu I可以通过过滤、洗涤等简单操作即可进行回收再利用,可重复使用4次产率没有明显降低. 相似文献
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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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1,3-共轭烯炔不仅是有机合成的重要中间体, 许多天然产物和具有生理活性的化合物的核心骨架都含有共轭烯炔单元, 在已有的共轭烯炔的合成方法中钯铜共催化的烯基卤与端炔的Sonogashira 偶联反应占据了统治地位. 炔卤化合物是一种独特有趣的有机分子, 它既能参与类似于端炔的偶联反应, 又具有卤苯的过渡金属氧化加成的性能, 这些特点使炔卤在构建复杂有机分子中起着重要的作用. 我们以Pd(OAc)2为催化剂, K2CO3为碱, 在DMF溶剂中实现了末端烯和炔基溴的交叉偶联反应高区域和立体选择性地合成1,3-共轭烯炔, 考察了催化剂的种类、碱的种类和温度对反应的影响. 研究结果表明: 5 mol% Pd(OAc)2, 2.5 equiv. K2CO3, 在DMF溶剂中, 不需要任何配体和添加剂, 炔基溴与苯乙烯衍生物于80 ℃, 与贫电子烯烃于室温反应2 h可以高产率得到所需产物, 所有化合物的结构用IR, 1H NMR, 13C NMR, MS, 高分辨质谱等方法进行了表征, 该偶联反应合成途径简捷、反应条件温和, 可为共轭烯炔化合物合成提供简便的途径. 相似文献
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《Arabian Journal of Chemistry》2022,15(8):103962
MOF-253·Pd(OAc)2 and MOF-253·CuI were prepared, characterized, and evaluated firstly as heterogeneous co-catalysts, which showed high catalytic activity in Sonogashira coupling reaction of various substituted (hetero)aryl halides with terminal alkynes at 70–120 °C, and afforded the corresponding products in 45–99% yields with high TON (~2722 for Pd). The best result was achieved with an extremely low Pd (0.036 mol%) and Cu (0.397 mol%) loading. Moreover, the catalysts can be reused at least five times without significantly reducing the activity. Besides, Hg(0) and PVP-poisoning experiments confirmed that the present catalysts were efficient and heterogeneous catalysts in this coupling reaction. 相似文献
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The oxidative coupling reactions of terminal alkynes with H‐phosphonates were explored using SiO2−NHC−Cu(II) (5.0 mol%) as catalyst at room temperature under base‐free reaction conditions. The reactions of a variety of terminal alkynes with H‐phosphonates generated the corresponding alkynylphosphonate products in good to excellent yields. In addition, SiO2−NHC−Cu(II) could be recovered and recycled for six consecutive trials without significant loss of its reactivity. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Pavel Drabina Petr Funk Aleš Růžička Jiří Hanusek Miloš Sedlák 《Transition Metal Chemistry》2010,35(3):363-371
The optically pure 6-(4-alkyl-4,5-dihydro-1,3-oxazol-2-yl)pyridine-2-carboxylates have been prepared from 6-methoxycarbonylpyridine-2-carboxylic
acid by a sequence of three reactions with the overall yield of 40–50%. Some of these compounds form stable complexes with
Cu(II) ions in non-aqueous medium. Their polymeric structure was determined in the solid phase by X-ray diffraction analysis.
The Cu(II) complexes were also used as catalysts for addition reactions of terminal alkynes to imines giving substituted propargylamines
with maximum yield 64% and 37% ee. 相似文献
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The reactions of nitrones with terminal alkynes, catalyzed by chiral (i)Pr-trisoxazoline 2a/Cu(ClO4)2.6H2O under air atmosphere, afforded beta-lactams in moderate to good yields with up to 85% ee. The diastereoselectivity depends on the alkyne. Propiolate gives the trans-isomer as a major product, while the other alkynes afford cis-disubstituted lactams predominantly. Copper(II) salt proved to be an efficient catalyst precursor for the first time in the Kinugasa reaction, and this allowed the reaction to be performed under a practical and convenient condition. An appropriate base used in this reaction was essential to control both diastereoselectivity and enantioselectivity. Compared with primary and tertiary amines, secondary amines gave higher enantioselectivities. The reaction scope and limitation as well as the mechanism were also studied. 相似文献
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Simple copper(II) hydroxide Cu(OH)(2) could act as an efficient heterogeneous catalyst for selective oxidative cross-coupling of a broad range of terminal alkynes and amides using air as a sole oxidant, giving the corresponding ynamides in moderate to high yields (56-93% yields). 相似文献
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Chiral tris(oxazoline)/Cu(I) complexes are demonstrated as a type of efficient catalysts for the asymmetric Kinugasa reaction of terminal alkynes with C-arylnitrones, providing a highly enantio- and diastereoselective access to optically active β-lactams. 相似文献
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A new type of activated carbon immobilized copper(Cu/AC) photocatalyst was prepared by a facile impregnation-adsorption method, where Cu2+ is chemically adsorbed by abundant oxygenated functional groups on large-surface-area activated carbon surface. Cu/AC exhibited good activity and selectivity to imine for the hydro-amination of alkynes at 60℃ under visible light irradiation. The reaction is initialized by the activation of alkynes molecules at Cu active sites with the aid of light as evidenced by the solid-state NMR and laser photolysis measurements and the control experiments. This strategy for catalyst design is potentially extended to the immobilization of other metal homogeneous catalysts for various heterogeneous catalytic systems. 相似文献
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Chassaing S Sani Souna Sido A Alix A Kumarraja M Pale P Sommer J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(22):6713-6721
For the first time, copper(I)-exchanged zeolites were developed as catalysts in organic synthesis. These solid materials proved to be versatile and efficient heterogeneous, ligand-free catalytic systems for the Huisgen [3+2] cycloaddition. These cheap and easy-to-prepare catalysts exhibited a wide scope and compatibility with functional groups. They are very simple to use, easy to remove (by filtration), and are recyclable (up to three times without loss of activity). Investigations with deuterated alkynes and deuterated zeolites proved that this Cu(I)-zeolite-catalyzed "click" reaction exhibited a mechanism different from that reported for the Meldal-Sharpless version. 相似文献
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吴兆轩 Heriberto Diaz Velazquez 闵梦蝶 原晔 Hussein A. Younus 陈建 Bibimaryam Mousavi Francis Verpoort 《化学通报》2015,78(3):220-225
近年来,催化CO2合成精细化学品的研究备受关注。本研究在温和条件下利用金属双氮杂环卡宾催化剂实现CO2与末端炔烃的直接羧化反应,并提出合理的催化机理。首先,合成制备了铜基、银基两种金属双氮杂环卡宾催化剂,实验证明银双氮杂环卡宾配合物具有较好催化活性。通过改变环境条件和底物种类,对反应条件及催化剂底物适应性进行了探究,利用核磁共振谱仪表征产物分子结构并计算直接羧化反应的催化产率。结果表明,适宜催化条件为:1.2eq Cs2CO3作为添加剂、1大气压、室温、无水溶剂和1(mmol)%催化剂用量。银基金属催化剂活性较铜基催化剂高并具有广泛的底物适应性,对苯乙炔的催化产率高达93%;对乙炔气体同样具有良好的催化活性。此类催化剂具有优良的催化活性,能催化合成丙炔酸等重要医药中间体,在工业应用上具有极大潜力和广阔前景。 相似文献
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EH Christen RJ Gübeli B Kaufmann L Merkel R Schoenmakers N Budisa M Fussenegger W Weber B Wiltschi 《Organic & biomolecular chemistry》2012,10(33):6629-6632
The Cu(i)-catalyzed cycloaddition of terminal azides and alkynes (click chemistry) represents a highly specific reaction for the functionalization of biomolecules with chemical moieties such as dyes or polymer matrices. In this study we evaluate the use of bicinchoninic acid (BCA) as a ligand for Cu(i) under physiological reaction conditions. We demonstrate that the BCA-Cu(i)-complex represents an efficient catalyst for the conjugation of fluorophores or biotin to alkyne- or azide-functionalized proteins resulting in increased or at least equal reaction yields compared to commonly used catalysts like Cu(i) in complex with TBTA (tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine) or BPAA (bathophenanthroline disulfonic acid). The stabilization of Cu(i) with BCA represents a new strategy for achieving highly efficient bioconjugation reactions under physiological conditions in many application fields. 相似文献