共查询到20条相似文献,搜索用时 15 毫秒
1.
Jalal Albadi 《合成通讯》2013,43(15):2019-2030
In this work, polymer-supported copper(I) iodide catalyst and macroporous polymer-supported azide reagent were used to simplify the synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from α-bromo ketones/amides/esters following green chemistry principles. This new one-pot protocol facilitates the workup of the reaction and provides the products in short times and excellent yields. Heterogeneous catalyst and reagent can be reused at least for five runs without significant yield decreases. 相似文献
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Kaushik Naskar Suvendu Maity Himadri Sekhar Maity Chittaranjan Sinha 《Molecules (Basel, Switzerland)》2021,26(17)
[Cu(CPA)(BDC)]n (CPA = 4-(Chloro-phenyl)-pyridin-4-ylmethylene-amine; BDC = 1,4-benzenedicarboxylate) has been synthesized and structurally characterized by single crystal X-Ray diffraction measurement. The structural studies establish the copper (II) containing 2D sheet with (4,4) square grid structure. The square grid lengths are 10.775 and 10.769 Å. Thermal stability is assessed by TGA, and subsequent PXRD data establish the crystallinity. The surface morphology is evaluated by FE-SEM. The N2 adsorption−desorption analysis demonstrates the mesoporous feature (∼6.95 nm) of the Cu-MOF. This porous grid serves as heterogeneous green catalyst with superficial recyclability and thermal stability and facilitates organic transformations efficiently such as, Click and Knoevenagel reactions in the aqueous methanolic medium. 相似文献
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A task-specific ionic liquid (IL, OPPh2) that bears a phosphinite weak Lewis base group in an imidazolium cation was found to efficiently catalyze the Knoevenagel condensation of arylaldehydes with malononitrile, dimethyl(diethyl)malonate, and ethyl cyanoacetate. This IL plays a dual role as both the reaction media and also catalyst, and it can be easily recovered and reused in several runs. Satisfactory results were obtained with good yields, short reaction time, and simplicity in the experimental procedure. A variety of coumarin derivatives were synthesized in this procedure. 相似文献
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Xin Ying ZHANG Yan Zhen LI Xue Sen FAN Gui Rong QU Xue Yuan HU Jian Ji WANG 《中国化学快报》2006,17(2):150-152
1, 4-Dihydropyridine (DHP) heterocyclic ring is a common feature of various bioactivecompounds such as vasodilator, bronchodilator and antiatherosclerotic, antitumor, andantidiabetic agents1. Due to their important pharmacological activities, many methods… 相似文献
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Basic Ionic Liquid: A Reusable Catalyst for Knoevenagel Condensation in Aqueous Media 总被引:1,自引:0,他引:1
GAO Guo-hua LU Liang ZOU Ting GAO Jin-bao LIU Ye HE Ming-yuan 《高等学校化学研究》2007,23(2):169-172
IntroductionThe Knoevenagel condensation of aldehydes/ketones and activated methylene compounds is one ofthe most common synthetic methods to produce func-tionalized alkenes. Theα,β-unsaturated productsobtained by this method have been widely used as th… 相似文献
6.
Regina Westphal Eclair Venturini Filho Laiza Bruzadelle Loureiro Cludio Francisco Tormena Claudia Pessoa Celina de Jesus Guimares Mariana Palmeira Manso Rodolfo Goetze Fiorot Vinicius Rangel Campos Jackson Antnio Lamounier Camargos Resende Fabrizio Medici Sandro Jos Greco 《Molecules (Basel, Switzerland)》2022,27(22)
In this work a microwave-assisted Knoevenagel/Michael/cyclization multicomponent domino methodology, using ethanol as solvent and the ionic liquid 1-methylimidazolium chloride as catalyst was developed for the synthesis of spiro compounds. The reaction conditions considered ideal were determined from a methodological study varying solvent, catalyst, amount of catalyst, temperature, and heating mode. Finally, the generality of the methodology was evaluated by exploring the scope of the reaction, varying the starting materials (isatin, malononitrile, and barbituric acid). Overall, the twelve spiro compounds were synthesized in good yields (43–98%) and the X-ray structure of compound 1b was obtained. In addition, the in vitro antiproliferative activities of the spirocycles against four types of human cancer cell lines including HCT116 (human colon carcinoma), PC3 (prostate carcinoma), HL60 (promyelocytic leukemia), and SNB19 (astrocytoma) were screened by MTT-based assay. It is noteworthy that spiro compound 1c inhibited the four cell lines tested with the lowest IC50 values: 52.81 µM for HCT116, 74.40 µM for PC3, 101 µM for SNB19, and 49.72 µM for HL60. 相似文献
7.
Abstract A task-specific ionic liquid, [H3N+–CH2–CH2–OH][CH3COO?], was successfully applied as an efficient and reusable catalyst for the one-pot domino to approach to dihydropyrano[3,2-c]chromene derivatives with atom economy in a condensation reaction of 4-hydroxycoumarin, aldehydes, and malononitrile in a combinatorial fashion. The reaction gave excellent yields within short reaction times at room temperature under solvent-free grinding conditions. The products and ionic liquid could be conveniently separated from the reaction mixture, indicating that the whole process was performed as a green chemical transformation. 相似文献
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A novel biochar-based graphitic carbon nitride was prepared through calcination of Zinnia grandiflora petals and urea. To provide acidic and ionic-liquid functionalities on the prepared carbon, the resultant biochar-based graphitic carbon nitride was vinyl functionalized and polymerized with 2-acrylamido-2-methyl-1-propanesulfonic acid, acrylic acid and the as-prepared 1-vinyl-3-butylimidazolium chloride. The final catalytic system that benefits from both acidic (–COOH and –SO3H) and ionic-liquid functionalities was applied as a versatile, metal-free catalyst for promoting some model acid catalyzed reactions such as Knoevenagel condensation and Biginelli reaction in aqueous media under a very mild reaction condition. The results confirmed high activity of the catalyst. Broad substrate scope and recyclability and stability of the catalyst were other merits of the developed protocols. Comparative experiments also indicated that both acidic and ionic-liquid functionalities on the catalyst participated in the catalysis. 相似文献
11.
Yiming Ren 《合成通讯》2013,43(11):1670-1676
Esterification of carboxylic acids and transesterification of β-ketoesters with alcohols have been developed using a catalytic amount of iodine in polyethylene glycol (PEG) ionic liquid (IL 1000) to afford the corresponding esters in good yields. By simple separation of the ionic-liquid phase containing the iodine, the system of I2/IL 1000 can be reused several times. 相似文献
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Abolghasem Davoodnia Amir Khojastehnezhad Mehdi Bakavoli Niloofar Tavakoli‐Hoseini 《中国化学》2011,29(5):978-982
Easily synthesized aldoximes have been converted to the corresponding nitriles under very mild conditions by a simple reaction using two halogen‐free SO3H‐functionalized ionic liquids, 3‐methyl‐1‐(4‐sulfonic acid)butylimi‐ dazolium hydrogen sulfate [MIM(CH2)4SO3H][HSO4] and 1‐(4‐sulfonic acid)butylpyridinium hydrogen sulfate [PY(CH2)4SO3H][HSO4], as catalyst and reaction medium without any additional organic solvent. The method was equally effective for aromatic aldoximes bearing electron‐donating and electron‐withdrawing substituents. Taking into account environmental and economical consideration, the protocol presented here has the merits of environmentally friendly, simple operation, easy work‐up and very good yields. The catalysts could be recycled and reused for several times without noticeably decreasing in their catalytic activities. 相似文献
14.
合成、表征了新型Bronsted-Lewis酸性离子液体1-(3-磺酸)-丙基-3-甲基咪唑氯锌酸盐([HO3S-(CH2)3-mim]Cl-ZnCl2),并将其用于催化松香二聚反应.结果表明,[HO3S-(CH2)3-mim]Cl-ZnCl2(ZnCl2摩尔分数x>0.5)为Bronsted和Lewis双酸性,且以[HO3S-(CH2)3-mim]Cl-ZnCl2 (x=0.64)的催化性能较佳.在松香5.0 g,甲苯15 g,离子液体质量分数5%,反应温度110℃和反应时间4 h的较佳实验条件下,所得产物聚合松香的软化点为118 ℃.此外,该催化剂的使用有利于产物的分离且分离的离子液体催化剂具有良好的重复使用性能. 相似文献
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A basic ionic liquid, [BmIm]OH was used as catalyst in the cyclocondensation of various kinds of vinylmalononitriles with nitroolefins in ethanol at reflux. A series of 2-amino-3-nitrobenzonitriles were obtained in reasonable yields. The straightforward and green protocol was found to be fairly efficient, and the catalyst could be recycled and reused in subsequent reactions with consistent activity. The mechanism of the reaction was discussed.
16.
Majid M. Heravi Masoumeh Zakeri Narges Karimi Mina Saeedi Hossien A. Oskooie Niloofar Tavakoli-Hosieni 《合成通讯》2013,43(13):1998-2006
2,4,5-Trisubstituted imidazoles have been synthesized in excellent yields (85–95%) in the presence of 5 mol% of [(CH2)4SO3HMIM][HSO4] as a Brønsted acidic ionic liquid. 相似文献
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Homogeneouscatalysisoffersmanyadvantagesoverheterogenouscatalysiswithrespecttoactivity ,selectivi ty ,flexibilityofoperation .However ,thecontinuouscat alystconsumption ,catalystremovalfromtheproductsandcatalystdisposalhavestilltobeimproved .Anat tractiveap… 相似文献
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Cyclopropanation of styrene with ethyl diazoacetate catalyzed by Pd(Ⅱ) in ionic liquid [omim][BF4] was investigated.Palladium catalysts can be effectively immobilized in ionic liquid.The catalysts PdCl2 and cyclopalladated complex 2 contained in ionic liquid could be recycled for 6 and 7 times,respectively,without losing the efficiency. 相似文献
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LIANG Da-peng XIN Xin GAO Han DUAN Hai-feng LIN Ying-jie . College of Environment Resources Jilin University Changchun P. R. China . College of Chemistry Changchun 《高等学校化学研究》2009,25(2)
A facile and efficient 1, 4-conjungate addition(Michael addition) reaction of active methylene compounds to α,β-unsaturated compounds, catalyzed by guanidinium lactate ionic liquid(IL9), has been developed. A range of chalcones and nitroalkenes together with active methylene compounds have been converted smoothly to the corresponding products in high yields. 相似文献
20.
An efficient and reusable heterogeneous catalyst with oxime‐derived palladacycle immobilized in an ionic liquid brush has been synthesized and an environmentally‐friendly procedure have been developed for coupling aryl iodides and bromides with acrylic acid. These reactions were conducted in neat water under aerobic conditions with water‐insoluble or even solid aryl halides and they proceeded smoothly and cleanly without any organic co‐solvent or other additives. The ionic liquid brush could be easily recovered and reused at least five times without significant loss of activity. The protocol has the advantages of excellent yields, environmental friendliness, and catalyst recyclability. 相似文献