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1.
Abstract Some novel long-chain nitrones, isoxazolines, and (1H-benzo[d]-imidazol-2-ylthio) derivatives were synthesized. Nitrones, N-{4-[2-(tetradecylthio)acetoxy]benzylidene}aniline oxide, and N-[4-(12-oxo-2,5,8,11-tetraoxadocosan-22-yloxy)benzylidene]aniline oxide were prepared via the reaction of β-phenylhydroxylamine with the corresponding aromatic aldehydes. The isoxazolines were prepared from undec-10-en-1-ol and benzonitrile-N-oxide which was generated in situ. The 1H-benzo[d]-imidazol-2-ylthio derivatives were synthesized via the replacement reaction of ω-bromo esters and 2-mercaptobenzimidazole. 相似文献
2.
Coventry DN Batsanov AS Goeta AE Howard JA Marder TB Perutz RN 《Chemical communications (Cambridge, England)》2005,(16):2172-2174
The selectivity of the iridium boryl complex-catalysed reaction of pyrene and perylene with B2(pin)2 (pin = OCMe2CMe2O) has been employed in the synthesis of D(2h)-symmetry pyrene-2,7-(Bpin)2 and D(4h)-symmetry perylene-2,5,8,11-(Bpin)4 providing direct borylation of positions which are otherwise difficult to derivatise. 相似文献
3.
Dr. Julia Merz Lena Dietrich Dr. Jörn Nitsch Dr. Ivo Krummenacher Prof. Dr. Holger Braunschweig Michael Moos David Mims Prof. Dr. Christoph Lambert Prof. Dr. Todd B. Marder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(52):12050-12059
We synthesized a series of new mono-, di-, tri- and tetra-substituted perylene derivatives with strong bis(para-methoxyphenyl)amine (DPA) donors at the uncommon 2,5,8,11-positions. The properties of our new donor-substituted perylenes were studied in detail to establish a structure-property relationship. Interesting trends and unusual properties are observed for this series of new perylene derivatives, such as a decreasing charge transfer (CT) character with increasing number of DPA moieties and individual reversible oxidations for each DPA moiety. Thus, (DPA)-Per possesses one reversible oxidation while (DPA)4-Per has four. The mono- and di-substituted derivatives display unusually large Stokes shifts not previously reported for perylenes. Furthermore, transient absorption measurements of the new derivatives reveal an excited state with lifetimes of several hundred microseconds, which sensitizes singlet oxygen with quantum yields of up to 0.83. 相似文献
4.
Mohamed Ali Elsayed Khalifa Ezzat Mohamed Zayed Mona Hassan Mohamed Mohamed Hilmy Elnagdi 《Journal of heterocyclic chemistry》1983,20(6):1571-1573
A novel synthesis of pyrazine derivatives from the reaction of α-tosyloximinonitriles with several active methylene enaminonitrile derivatives is reported. The reaction sequence is discussed. 相似文献
5.
A sulfamic acid–catalyzed synthesis of 3-alkylidene indolone derivatives by addition of dialkyl acetylenedicarboxylate to isatin derivatives in the presence of aniline is reported. The reaction sequence consists of an initial Michael addition of aniline to dialkyl acetylenedicarboxylate, followed by aldol-like reaction with isatin, and then elimination of aniline to afford the product. 相似文献
6.
Roubelakis MM Murata Y Komatsu K Orfanopoulos M 《The Journal of organic chemistry》2007,72(18):7042-7045
The synthesis of 10 new open-cage fullerene derivatives with a 16-membered-ring orifice is being reported. These compounds, derived from the regioselective addition reaction of an aromatic hydrazine or hydrazone to isomeric diketone derivatives of C(60), were isolated in moderate to excellent yields. 相似文献
7.
Barluenga J Lonzi G Riesgo L Tomás M López LA 《Journal of the American Chemical Society》2011,133(45):18138-18141
The copper(II)-catalyzed reaction of alkenyldiazo compounds with iodosylbenzene leading to β-oxodiazo derivatives is reported. This process occurs via an unprecedented 1,2-shift of the diazoacetate function. A selection of the synthetic applications of a representative member of this new class of functionalized diazo derivatives in the regioselective synthesis of substituted 1,4-dicarbonyl compounds is also reported. 相似文献
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9.
Facile Synthesis of Some Novel Tetrasubstituted 2,4‐Diaminopyrimidine Derivatives in Aqueous Glucose Solution as a Fully Green Medium and Promoter 下载免费PDF全文
A novel environmentally benign method toward the synthesis of some novel tetrasubstituted 2,4‐diaminopyrimidine derivatives using an aqueous glucose‐mediated one‐pot three‐component reaction of malononitrile with various benzaldehyde and amidine derivatives is reported. Some pyrimidine derivatives possessing α‐amino acid moiety were synthesized by the present protocol for the first time. This protocol offers advantages including facile reaction conditions, using naturally occurring glucose as promoter and water as solvent, simple work‐up, relatively short reaction times, and high yields of the products. 相似文献
10.
高效和可重复使用的Zr-MCM-41催化剂催化Strecker反应合成氨基腈类化合物(英文) 总被引:1,自引:0,他引:1
The synthesis and characterization of Zr-MCM-41 nanoreactors and their catalytic activity in the synthesis of new amino nitrile derivatives by the Strecker reaction in high yields and in short reaction times is reported. 相似文献
11.
Karell Pérez-Labrada Edwin Flórez-LópezEvelyn Paz-Morales Luis D. Miranda Daniel G. Rivera 《Tetrahedron letters》2011,52(14):1635-1638
A two-step practical synthesis of dehydroalanine derivatives from commercially available starting materials is reported. The approach comprises an Ugi four-component reaction using 2-benzoylacetaldehyde, followed by an elimination process of the benzoate group. This protocol provided access to several dehydroalanine derivatives modified with diverse functional groups, which might be useful for further transformations in the construction of more complex molecules. 相似文献
12.
Fatemeh Sheikholeslami-Farahani Zinatossadat Hossaini Faramarz Rostami-Charati 《中国化学快报》2014,25(1):152-154
A straightforward and efficient method for the synthesis of thiopyran derivatives via three-component reaction of alkyl propiolate, benzoylisothiocyanate or its derivatives and α-haloketones in the presence of triphenylphosphine under solvent-free conditions at 70℃ without using any catalyst is reported, The method offers several advantages including high yields of products and an easy work-up procedure. 相似文献
13.
Via one-step copper catalyzed procedures it was possible to synthesize 2,5,8,11-tetrabromo, tetrachloro, and tetracyano derivatives of perylenediimides. Characterization of optical and electrochemical properties of these materials proves substantial enhancement of the electron affinity, with a LUMO level as low as -4.4 eV in the case of the tetracyano perylenediimide. 相似文献
14.
A novel method for the synthesis of gem-dialkoxycarbonylcyclopropane derivatives is reported which involves the reaction of olefins with dibromomalonic esters and Cu in dimethyl sulphoxide. The reaction was applicable to a wide range of olefins and proceeded smoothly at moderate temperature to give the cyclopropane derivatives often in good yields. Cu was converted to Cu(II) bromide during the reaction. The reaction was weakly electrophilic and proceeded non-stereospecifically, and a stepwise mechanism involving addition and elimination appeared favourable for the reaction. In contrast, in the previously reported examples of the cyclopropanation of olefins by organic gem-dihalides and Cu in an aromatic hydrocarbon, Cu was converted to Cu(I) halides and a concerted cycloaddition of carbenoid intermediates appeared favourable. 相似文献
15.
Barluenga J Calleja J Antón MJ Alvarez-Rodrigo L Rodríguez F Fañanás FJ 《Organic letters》2008,10(20):4469-4471
A new, mild, one-pot method for the synthesis of cyclobutabenzenes by the zirconium-promoted cross-coupling reaction of aryllithium compounds and alkenyl bromides is reported. Formation of an arynezirconocene complex and its regioselective coupling with an alkenyl bromide are the key steps of the process. This method allows the regio- and diastereoselective synthesis of functionalized cyclobutabenzene derivatives from simple and easily available starting materials. 相似文献
16.
Pingping Li Jian Sun Xiaohe Xu Zhisheng Mi Yuyan Lin Jingya Cheng Renren Bai Yuanyuan Xie 《Tetrahedron letters》2018,59(27):2640-2643
A ferric nitrate-promoted cross-dehydrogenative coupling reaction of N-hydroxyphthalimide (NHPI) with toluene derivatives is reported. The reaction proceeded smoothly using molecular oxygen as an oxidant, providing an efficient method for the synthesis of N-hydroxyimide esters. Furthermore, a plausible mechanism was proposed. 相似文献
17.
Péter Ábrányi-Balogh András Dancsó Dávid Frigyes Balázs Volk György Keglevich Mátyás Milen 《Tetrahedron》2014
In the present work, a practical synthesis of 1-aryl-β-carboline-3-carbaldehydes as versatile building blocks and their application in Biginelli reaction is reported. The starting material of the four-step synthesis is racemic tryptophan methyl ester. The procedure involves a Pictet–Spengler cyclization, a dehydrogenation, an ester reduction, and an alcohol oxidation step. The β-carboline-3-carbaldehydes were further transformed using a Biginelli reaction into derivatives containing a pharmacologically significant dihydropyrimidine ring at position-3. 相似文献
18.
A gold-catalyzed three-component coupling reaction (A3 reaction) was developed as an efficient approach for the synthesis of challenging 2,4-disubstituted quinoline derivatives. Compared to previously reported Cu/Au bi-catalyst system, this protocol enables achieving A3 reaction only in the presence of triazole-gold catalyst. Notably, 4-alkyl substituted or 2-alkyl substituted quinoline derivatives were obtained with good yields, which highlighted the unique advantage of this new strategy. 相似文献
19.
An efficient total synthesis of flavans from the reactions of salicylaldehyde and acetophenone derivatives is reported. The synthesis involves preparation of chalcones through an aldol reaction followed by reduction of both the double bond and the ketone using NaBH4 and an acetic acid mediated cyclization. Methoxy groups on the aromatic rings did not affect significantly the yields of the procedure. 相似文献
20.
Unnikrishnan Vettukattil Avudaiappan Govindan Kiran James Ajay Anilkumar Sreekumar Krishnapillai 《Journal of heterocyclic chemistry》2021,58(12):2348-2358
The synthesis of highly functionalized piperidine derivatives using amine functionalized maltitol-cored dendritic polymer (MAL-G0) in acetonitrile as the reaction medium is reported. A variety of piperidine derivatives were synthesized and the reaction gave an excellent yield of 89%–95%. The highly functionalized nature of the catalyst provided large number of active sites which resulted in good yield within a short period of time. Maltitol is a carbohydrate polyol system which was chosen here as the core for the synthesis of the dendritic catalyst; it was an effective approach for the preparation of piperidine like medicinal compounds. Maltitol-cored dendritic polymer was effectively synthesized and characterized using GPC, TG, UV–Visible, IR, and NMR techniques and also all the synthesized piperidine derivatives were characterized using LCMS, IR, and NMR techniques. 相似文献