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1.
The novel substituted 2,3-dichloro-1,4-naphthoquinone derivatives were synthesized from the reactions of (1) and related nucleophilles in sodium carbonate (Na2CO3) solution of ethanol, chloroform with Et3N, or potassium carbonate (K2CO3) solution of acetonitrile. The structures of novel compounds were characterized by using microanalysis, Fourier transform–infrared, 1H NMR, 13C NMR, mass spectrometry, and cyclic voltammetry (CV).
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
2.
Design,Synthesis, and Herbicidal Activities of 3‐Aryl‐4‐substituted‐5‐[3‐(trifluoromethyl)phenoxy]‐1,2,4‐triazoles
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In order to find novel bleaching herbicide lead compounds, a series of novel 3‐aryl‐4‐substituted‐5‐[3‐(trifluoromethyl)phenoxy]‐1,2,4‐triazoles were designed and synthesized by the multi‐step reactions. N‐(Arylformamido)phenylthioureas undergo ring closure in the presence of sodium hydroxide to generate 3‐aryl‐4‐substituted‐4H‐[1,2,4]triazol‐5‐thiols 1 , which reacted with methyl sulfate in the presence of K2CO3 to give 3‐aryl‐5‐methylsulfanyl‐4‐substituted‐4H‐[1,2,4]triazoles 2 . The target compounds 4 were synthesized by the oxidation of 2 in the presence of H2O2 and Na2WO4, followed by the substitution with 3‐(trifluoromethyl)phenol in moderate to good yields. Their structures were confirmed by IR, 1H NMR, EI–MS, and elemental analyses. The preliminary bioassay indicated that some of them displayed moderate to good selective herbicidal activity against Brassica campestris L at the concentration of 100 µg/mL. Compounds 4c and 4i possessed 75.0% and 82.6% inhibition against Brassica campestris L at the concentration of 100 µg/mL. However, the target compounds 4 showed weak herbicidal activity against Echinochloa crus‐galli at the concentration of 100 and 10 µg/mL. 相似文献
3.
New bis(thio)substituted, S‐,O‐substituted, and S‐,S‐substituted benzoquinone compounds were synthesized from the reaction of p‐chloranil ( 1 ) with S‐,O‐substituted thiols, dithiols, and monothiols. The 13C NMR spectra and the IR spectra of heterocyclic compounds 3 , 4 and 7 , 8 showed different behavior; that of 3 , 7 showed a carbon signal and a >CO group band for the carbonyl group and that of 4 , 8 showed two carbon signals and split bands for the carbonyl group. The structures of the novel compounds were characterized by microanalysis, FT‐IR, 1H NMR, 13C NMR, MS, and UV–vis spectroscopy. The crystal structure of 2,3,5,6‐tetrakis(4‐fluorobenzylthio)cyclohexa‐2,5‐diene‐1,4‐dione ( 15 ) was determined by the X‐ray diffraction method. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:446–452, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20634 相似文献
4.
A series of new, 2‐substituted 3‐aryl‐8,9,10,11‐tetrahydro‐5‐methyl[1]benzothieno[3′,2′ : 5,6]pyrido[4,3‐d]pyrimidin‐4(3H)‐ones, compounds 5a – q , were designed and synthesized via the aza‐Wittig reaction as the key step. The iminophosphorane 1 reacted with phenyl isocyanate (or 4‐chlorophenyl isocyanate) to the carbodiimide 4 , which was cyclized to 5 upon addition of different amines, EtOH, or phenols in the presence of a catalytic amount of EtONa or K2CO3 (Schemes 1 and 2). The structures of compounds 5 were confirmed by IR, 1H‐ and 13C‐NMR, EI‐MS, elemental analyses, and, in the case of 5l , by single‐crystal X‐ray diffraction (Figure). 相似文献
5.
Tomáš Weidlich Libor Dušek Barbora Vystrčilová Aleš Eisner Petr Švec Aleš Růžička 《应用有机金属化学》2012,26(6):293-300
The potential catalytic activity of selected C,N‐chelated organotin(IV) compounds (e.g. halides and trifluoroacetates) for derivatization of both dimethyl carbonate (DMC) and diethyl carbonate (DEC) was investigated. Some tri‐, di‐ and monoorganotin(IV) species (LCN(n‐Bu)2SnCl (1), LCN(n‐Bu)2SnCl.HCl (1a), LCN(n‐Bu)2SnI (2), LCNPh2SnCl (3), LCNPh2SnI (4), LCN(n‐Bu)SnCl2 (5), LCNSnBr3 (6) and [LCNSn(OC(O)CF3)]2(μ‐O)(μ‐OC(O)CF3)2 (7)) bearing the LCN moiety (LCN = 2‐(N,N‐dimethylaminomethyl)phenyl‐) were assessed as catalysts for reactions of both DMC and DEC with various substituted anilines. The catalytic activities of 4 and 7 for derivatization of DMC with p‐substituted phenols were studied for comparison with the standard base K2CO3/Silcarbon K835 catalyst (catalyst 8). The composition of resulting reaction mixtures was monitored by multinuclear NMR spectroscopy, GC and GC‐MS techniques. In general, catalysts 1, 3 and 7 exhibited the highest catalytic activity for all reactions studied, while some of them yielded selectively carbonates, carbamates, lactam or substituted urea. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
6.
Hong Shi Tao Wu Peng Jiang Xiaodong Jin Hongjun Zhu 《Journal of heterocyclic chemistry》2014,51(Z1):E71-E76
Seven novel fluorescence‐traced 1‐aryl‐2‐substituted‐3‐allyl‐1H‐benzimidazolium bromides ( 5a , 5b , 5c , 5d , 5e , 5f , 5g ) were synthesized by alkylation and quaternization of compounds 1‐aryl‐2‐substituted‐1H‐benzimidazoles ( 4a , 4b , 4c , 4d , 4e , 4f , 4g ) with excess allyl bromide in acetonitrile at refluxing temperature. Their structures were characterized by 1H‐NMR, MS, and elemental analysis. They emit violet‐blue light (λEmmax = 386–438 nm) with fluorescence quantum yields of 0.54 to 0.75 in aqueous solution. 相似文献
7.
Cemil Ibis Sibel Sahınler Ayla Senol Yavuz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):492-502
Abstract Novel thio- and alkoxy-substituted benzoquinone derivatives were synthesized from the reactions of p-chloranil (1) and related nucleophiles in a sodium carbonate (Na2CO3) solution of acetonitrile or in chloroform with Et3N. The structures of novel compounds were characterized by using microanalysis, FTIR, 1H NMR, 13C NMR, MS, CV, and fluorescence spectroscopy. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
8.
Guang‐Fan Han Ming Wang Li‐Zhuang Chen Xiao‐Lei Hu 《Journal of heterocyclic chemistry》2012,49(4):909-912
The Knoevenagel reactions of malononitrile with acetophenone or 4‐substituted acetophenons were carried to give the corresponding 2‐(1‐aryle thylidene)malononitriles, which was further cyclized with sulfur using NaHCO3 as catalysts to generate 2‐amino‐5‐arylthiophene‐3‐carbonitrile 2 . The intermediate enamines 3 were prepared by refluxing of 2 with 5‐substituted‐1,3‐cyclohexanedione using p‐toluenesulfonic acid as catalyst. The title compounds 4‐amino‐3‐aryl ‐7‐substituted‐7,8‐dihydrothieno[2,3‐b]quinolin‐5(6H)‐one were synthesized by cyclization of 3 in the presence of K2CO3 and Cu2Cl2. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1H‐NMR spectra. 相似文献
9.
10.
Starting from ethyl propionylacetate, and ethyl 2‐ethylacetoacetate we prepared 4‐propyl‐7,8‐, 4‐propyl‐6,7‐, 3‐ethyl‐4‐methyl‐7,8‐ and 3‐ethyl‐4‐methyl‐6,7‐dihydroxy‐2H‐chromenones which were allowed to react with the bis‐dihalides or ditosylates of glycols in DMF/Na2CO3 to afford the 6,7‐ and 7,8‐chromenone derivatives of 12‐crown‐4, 15‐crown‐4 and 18‐crown‐6. The products were identified using ir, 13C and 1H nmr, ms and high resolution mass spectroscopy. The cation selectivities of chromenone crown ethers with Li+, Na+ and K+ cations were estimated from the steady state emission fluorescence spectra of free and cation complexed chromenone macrocyclic ethers in acetonitrile. 相似文献
11.
Musa Özil Fatih İslamoğlu Emre Menteşe Bahittin Kahveci 《Helvetica chimica acta》2010,93(10):1967-1974
The novel 4‐amino‐ or 4‐aryl‐substituted 2,4‐dihydro‐5‐[(4‐trifluoromethyl)phenyl]‐3H‐1,2,4‐triazol‐3‐ones 3a – 3g were synthesized by reaction of N‐(ethoxycarbonyl)‐4‐(trifluoromethyl)benzenehydrazonic acid ethyl ester ( 2 ) and primary amines or hydrazine by microwave irradiation. Compounds 3a – 3g were potentiometrically titrated with tetrabutylammonium hydroxide (Bu4NOH) in four nonaqueous solvents, i.e., iPrOH, tBuOH, MeCN, and N,N‐dimethylformamide (DMF). Also half‐neutralization potential values and the corresponding pKa values were determined in all cases. 相似文献
12.
Zhong‐Xia Wang Li‐Zhuang Chen Bei Li Guang‐Fan Han 《Journal of heterocyclic chemistry》2015,52(6):1663-1668
The Gewald reactions of 5‐substituted‐1,3‐cyclohexanedione, malononitrile, and powdered sulfur were carried out to give the corresponding products 2‐amino‐5‐substituted‐7‐oxo‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile derivatives 1 . The intermediate enamines 2 were prepared by reaction of compounds 1 and 5‐substituted‐1,3‐cyclohexanedione with hydrochloric acid as catalyst. The title compounds 11‐amino‐2,8‐substituted‐2,3,8,9‐tetrahydrobenzo[4,5]thieno[2,3‐b]quinolinone 3 were synthesized by cyclization of compounds 2 in the presence of K2CO3 and Cu2Cl2. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1H‐NMR spectra. 相似文献
13.
Dr. Fawang Chen Dr. Xiaofang Li Prof. Dr. Bo Wang Dr. Tiegang Xu Dr. Shi‐Lu Chen Dr. Peng Liu Prof. Dr. Changwen Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(32):9870-9876
CoII‐substituted α‐Keggin‐type 12‐tungstenphosphate [(n‐ C4H9)4N]4H[PW11Co(H2O)O39]‐ (PW11Co) is synthesized and used as a single‐component, solvent‐free catalyst in the cycloaddition reaction of CO2 and epoxides to form cyclic carbonates. The mechanism of the cycloaddition reaction is investigated using DFT calculations, which provides the first computational study of the catalytic cycle of polyoxometalate‐catalyzed CO2 coupling reactions. The reaction occurs through a single‐electron transfer from the doublet CoII catalyst to the epoxide and forms a doublet CoIII–carbon radical intermediate. Subsequent CO2 addition forms the cyclic carbonate product. The existence of radical intermediates is supported by free‐radical termination experiments. Finally, it is exhilarating to observe that the calculated overall reaction barrier (30.5 kcal mol?1) is in good agreement with the real reaction rate (83 h?1) determined in the present experiments (at 150 °C). 相似文献
14.
Synthesis and Characterization of 11‐Amino‐3‐methoxy‐8‐substituted‐12‐aryl‐8,9‐dihydro‐7H‐chromeno[2,3‐b]quinolin‐10(12H)‐one Derivatives
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Guangfan Han Jiawei Du Lizhuang Chen Lijun Zhao 《Journal of heterocyclic chemistry》2014,51(4):1094-1099
A series of 2‐amino‐7‐methoxy‐4‐aryl‐4H‐chromene‐3‐carbonitrile compounds 2 were obtained by condensation of 3‐methoxyphenol with β‐dicyanostyrenes 1 in absolute ethanol containing piperidine. The intermediate enamines 3 were prepared by compounds 2 with 5‐substituted‐1,3‐cyclohexanedione using p‐toluenesuflonic acid (TsOH) as catalyst. The title compounds 11‐amino‐3‐methoxy‐8‐substituted‐12‐aryl‐8,9‐dihydro‐7H‐chromeno[2,3‐b]quinolin‐10(12H)‐one 4 were synthesized by cyclization of the intermediate enamines 3 in THF with K2CO3 /Cu2Cl2 as catalyst. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1H NMR spectra. The crystal structure of compound 4i was determined by single‐crystal X‐ray diffraction analysis. 相似文献
15.
Ekaterina S. Smirnova Anna A. Melekhova Vladislav V. Gurzhiy Stanislav I. Selivanov Dmitrii V. Krupenya Dr. Igor O. Koshevoy Prof. Dr. Sergey P. Tunik 《无机化学与普通化学杂志》2012,638(2):415-422
Reactions of [Cu(NCMe)4]+ with stoichiometric amount of diphosphine R2P–(C6H4)n–PR2, (R = NC4H4, n = 1; R = Ph, n = 1, 2, 3) or tri‐phosphine 1, 3, 5‐(PPh2–C6H4–)3–C6H3 ligands give the corresponding di‐ or trinuclear copper(I) acetonitrile‐phosphine complexes 1 – 5 . Substitution of the labile acetonitrile groups with chelating aromatic diimines – 2, 2′‐bipyridine (bpy), 1, 10‐phenanthroline (phen), 5, 6‐dimethyl‐1, 10‐phenanthroline (dmp), 5, 6‐dibromo‐1, 10‐phenanthroline (phenBr2) – gives the corresponding substituted compounds 6 – 16 . In all complexes 1 – 16 each central CuI atom has tetrahedral configuration completed with two N‐ and two P‐donor groups. The compounds obtained were characterized using elemental analysis, ESI‐MS, X‐ray crystallography, and NMR spectroscopy. All phosphine‐diimine compounds 6 – 16 are photoluminescent at room temperature both in dichloromethane solution and in solid state (λex = 385 nm). In CH2Cl2 solution the maxima of emission bands are found in a range 540–640 nm, and in solid in a similar range 538–620 nm. Emission of 6 – 16 is assigned to the triplet excited state dominated by the charge transfer transitions with contribution of the MLCT character. 相似文献
16.
Guang‐Fan Han Ming Wang Yan Jin Li‐Zhuang Chen 《Journal of heterocyclic chemistry》2014,51(3):648-655
We report on a novel method for the preparation of a new series of benzochromeno[2,3‐b]tetrahydroquinolin‐1‐one derivatives. The title compounds are prepared by the 5‐substituted‐1,3 ‐cyclohexanedione and 3‐amino‐1‐aryl‐1H‐benzo[f]chromene‐2‐carbonitrile or 2‐amino‐4‐aryl‐4H‐benzo[h]chromene‐3‐carbonitrile using dilute HCl, K2CO3, and Cu2Cl2 as catalysts. The method has the advantages of simple operation, high efficiency, and low toxicity. The structures of all compounds are characterized by elemental analysis, IR, MS, and 1H NMR spectra. Two single crystals are characterized by using X‐ray diffraction. 相似文献
17.
A series of novel N-, S-, and O-substituted p-chloranil derivatives were synthesized from the reactions of p-chloranil (1) and related nucleophiles in sodium carbonate (Na2CO3) solution of acetonitrile or in chloroform with Et3N. The structures of novel compounds were characterized by using microanalysis, Fourier transform–infrared, 1H NMR, 13C NMR, and mass spectrometry. 相似文献
18.
Markus Horn Herbert Mayr Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(25):7478-7487
First‐order rate constants kw for the reactions of a series of donor‐substituted triphenylmethylium (tritylium) ions with water in aqueous acetonitrile have been determined photometrically at 20 °C using stopped‐flow and laser‐flash techniques. The rate constants follow the linear free energy relationship log k(20 °C)=s(N+E). The reactivities kw of the methyl‐ and methoxy‐substituted tritylium ions towards water correlate linearly with the corresponding pK values with a Leffler–Hammond coefficient α=δΔG≠/δΔG0 of 0.62. The amino‐substituted compounds react more slowly than expected from the correlation of the less stabilized systems. Quantum chemical calculations of tritylium ions and the corresponding triarylmethanols and 1,1,1‐triarylethanes have been performed at the MP2(FC)/6‐31+G(2d,p)//B3LYP/6‐31G(d,p) level. The calculated gas‐phase hydroxide and methyl anion affinities of the tritylium ions correlate linearly with a slope of unity, indicating that the relative anion affinities do not depend on the nature of the anion. The pK values of the methyl‐ and methoxy‐substituted tritylium ions correlate linearly with the calculated gas‐phase hydroxide affinities, and the slope of this correlation shows that the differences in carbocation stabilities in the gas phase are attenuated to 66 % in solution. Mono‐ and bis(dimethylamino)‐substituted derivatives deviate from this correlation; their pK values are higher than expected from their calculated gas‐phase hydroxide affinities, which is explained by the extraordinary solvation of unsymmetrically amino‐substituted tritylium ions. Complete free‐energy profiles for the solvolyses of substituted trityl benzoates in 90:10 (v/v) acetonitrile/water have been constructed. 相似文献
19.
Sophie Laurent Franois Botteman LuceVander Elst RobertN. Muller 《Helvetica chimica acta》2004,87(5):1077-1089
In our efforts of finding new specific contrast agents of higher relaxivity and selectivity, we have prepared the two new benzyl‐functionalized DTPA (‘diethylenetriamine pentaacetate’) gadolinium complexes (S)‐ 3 and (R,S)‐ 4 , and compared their properties with those of the known regioisomers (S)‐ 2 and (S)‐ 1 . The theoretical fitting of the reduced transverse relaxation rates of the 17O‐nucleus of H2O gave values for the water‐residence time (τM) of 86–143 ns at 310 K, values that are not limiting the proton relaxivity at body temperature. 1H‐NMRD (nuclear magnetic‐relaxation dispersion) Profiles showed that the relaxivity of 1 – 4 (r1=4.3–5.1 s?1 mM ?1 at 20 MHz and 310 K) is higher than for the Gd? DTPA parent compound 5 . Transmetallation assessment demonstrated that all substituted compounds, except for (S)‐ 2 , are more stable than 5 . The highest stability towards Zn2+‐induced transmetallation was achieved with complexes 3, 1 , and 4 (in decreasing order). Apparently, the steric hindrance of the benzyl substituents in positions 5, 4, and 2, respectively, favorably reduces the accessibility of Zn ions. From a synthetic point of view, 4‐substituted DTPA complexes of type 1 are more readily accessible than 5‐substituted compounds of type 3 . Therefore, the former seem to be superior for linking substituted DTPA complexes to macromolecules or specific vectors. 相似文献
20.
Abdelwareth A. O. Sarhan Hassa N. A. H. Elsherif Abdalla M. Mahmoud Osama M. A. Habib 《Journal of heterocyclic chemistry》2008,45(3):897-907