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1.
A novel conversion of 2, 4‐diaryl‐2, 3‐dihydro‐1 H‐1, 5‐benzodiazepins into 2, 4‐diaryl‐3 H‐1, 5‐benzodiazepines by the reaction with m‐chloroperbenzoic acid (MCPBA) was reported.  相似文献   

2.
肖吉昌  陈庆云 《中国化学》2003,21(7):898-903
Heating a mixture of 1, 3-diiodo-1, 1, 3, 3-tetrafluoropropane (2), K2CO3, pyridinium bromides (3) in CH3CN at 65℃ for 10 h gives the corresponding trifluoromethylindolizines.  相似文献   

3.
Three copper(II) coordination polymers (CuCPs), namely, [Cu0.5(1,4‐bib)(SO4)0.5]n ( 1 ), {[Cu(1,3‐bib)2(H2O)] · SO4 · H2O}n ( 2 ), and [Cu(bpz)(SO4)0.5]n ( 3 ), were assembled from the reaction of three N‐donors [1,4‐bib = 1,4‐bis(1H‐imidazol‐4‐yl)benzene, 1,3‐bib = 1,3‐bis(1H‐imidazol‐4‐yl)benzene, and Hbpz = 3‐(2‐pyridyl)pyrazole] with copper sulfate under hydrothermal conditions. Their structures were determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses (EA), IR spectroscopy, powder X‐ray diffraction (PXRD), and thermogravimetric analyses (TGA). Structure analyses reveal that complex 1 is a 3D 6‐connected {412 · 63}‐ pcu net, complex 2 is a fourfold 3D 4‐connected 66‐ dia net, whereas complex 3 is a 1D snake‐like chain, which further expanded into 3D supramolecular architectures with the help of C–H ··· O hydrogen bonds. Moreover, the photocatalytic tests demonstrate that the obtained CuCPs are photocatalysts in the degradation of MB with the efficiency is 86.4 % for 1 , 75.3 % for 2 , and 91.3 % for 3 after 2 h, respectively.  相似文献   

4.
A method for the simultaneous preconcentration of Cu2+,Zn2+ and Fe3+ ions, in some food samples has been reported. The method is based on the adsorption of 3‐(1‐(1‐H‐indol‐3‐yl)‐3‐phenylallyl)‐1H‐indole (IPAI) loaded on Duolite XAD 761. The metal ions adsorbed on the modified solid phase resin are eluted using 6 mL of 4 mol L?1 nitric acid. The influences of the analytical parameters including pH and amount of ligand and solid phase and type and amount of surfactant and sample volume on the metal ions recoveries were investigated. The effects of matrix ions on the retentions of the analytes were also examined. The recoveries of analytes were generally higher than 95% with a RSD lower than 5%. The method has been successfully applied for these metals content evaluation in some real samples.  相似文献   

5.
Dehydrogenation by IBX/p‐TsOH is applied to the conversion of 3‐benzoyl propionates/propionamides to 3‐benzoyl acrylates/acrylamides in moderate to excellent yields. The reaction time for the dehydrogenation of 3‐benzoyl propionamides was remarkably shorter than that for the dehydrogenation of esters.  相似文献   

6.
The 13 C NMR resonances of 19 1‐acyl‐3‐(2‐nitro‐5‐substitutedphenyl)‐4,5‐dihydro‐1H‐pyrazoles, and 19 1‐acyl‐3‐(2‐amino‐5‐substituted)‐4,5‐dihydro‐1H‐pyrazoles, were completely assigned using the concerted application of one‐ and two‐dimensional NMR experiments (DEPT, gs‐HSQC and gs‐HMBC). Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

7.
1 INTRODUCTIONInrecentyears ,triazolo[3,4, b] 1 ,3,4 thiadiazolederivativeshavebeenat tractingmuchattentionfromchemistsandpharmacologistsbecausetheyshowbroadspectraofbiologicalactivities,suchasinsecticidal[1 ] ,antifungal[2 ] ,herbicidal[3] ,an tibacterial[4] ,hypotensiv…  相似文献   

8.
Several 1-alkyl-2-methylazetidin-3-ones were prepared in good yield by the hydride-induced cyclization of the corresponding β-bromo-α,α-dimethoxyketimines, the resulting 3,3-dimethoxyazetidines being hydrolyzed by acid. Imination of these 1,2-disubstituted azetidin-3-ones, followed by alkylation under kinetic control conditions resulted in regioisomeric mixtures of 2,4- and 2,2-dialkylated compounds. Analytical samples of the major 2,4-disubstituted derivatives were obtained after extensive chromatographic separation. The cis stereochemistry of the major 2,4-dialkylated isomer was demonstrated on the basis of NMR data.  相似文献   

9.
In order to investigate the biological activity of novel bis-pyrazole compounds,a series of N-(3-alkyl-5-(N-methylcarbamyl)- 1H-pyrazol-4-yl)-3-alkyl-4-substituted-1H-pyrazole-5-carboxamides were designed and synthesized with ethyl 3-alkyl-1H-pyrazole -5-carboxylate 1 as starting materials.N-Methyl-3-alkyl-4-amino-1H-pyrazole-5-carboxamides 6 were obtained from 1 via 5 steps.3-Alkyl-4-substitued-1H-pyrazole-5-carboxyl chlorides 4a,4b,11a,11b,11c or 12 were also obtained from 1 via several steps.Target compounds 7a-7g were obtained after the reaction of 6 with the above 1H-pyrazole-5-carboxyl chlorides.Preliminary bioassay showed some compounds possessing good inactivation effect against TMV(tobacco mosaic virus).Compound 7a showed higher activity superior to ningnanmycin at a concentration of 5.0×10-4 g/mL and equal activity at 1.0×10-4 g/mL;7b and 7c showed equal activity to virazole both at concentrations of 5.0×10-4 g/mL and 1.0×10-4 g/mL.  相似文献   

10.
A simple and efficient synthesis of novel 2‐heteroaryl‐substituted 1H‐indole‐2‐carboxylates and γ‐carbolines, compounds 1 – 3 , from methyl 2‐(2‐methoxy‐2‐oxoethyl)‐1‐methyl‐1H‐indole‐3‐carboxylate ( 4 ) by the enaminone methodology is presented.  相似文献   

11.
Three kinds of ionic liquids, 1-alkyl-3-methylimidazolium tetrafluoroborate (n=2–4), were prepared and fundamental properties of ionic liquids and those mixed with industrially used organic solvents (PC, GBL and AN) were investigated compared to solid salts, TEMABF4. It was found that degree of ionization of the ionic liquids were almost same as that of TEMABF4 from the conductivity measurement in diluted system of PC. The ionic liquids and the organic solvents intermingle with each other. Some enhancement in conductivity was observed compared to TEMABF4.  相似文献   

12.
三芳基缩二胺与烷基硫脲在二氧六环回流条件下反应, 可生成1-烷基-4,6-二芳基四氢三嗪硫酮化合物3。利用芳香醛, 烷基硫脲和醋酸铵一锅法也能得到3, 而三芳基缩二胺与芳基硫脲反应, 则生成了咪唑啉的硫氰酸盐。室温下,在相转移催化剂TEBA存在时, 3可被高锰酸钾氧化, 得到1-烷基-4,6-二芳基-2(1H)三嗪酮化合物。  相似文献   

13.
The reaction of 1H‐imidazole‐4‐carbohydrazides 1 , which are conveniently accessible by treatment of the corresponding esters with NH2NH2?H2O, with isothiocyanates in refluxing EtOH led to thiosemicarbazides (=hydrazinecarbothioamides) 4 in high yields (Scheme 2). Whereas 4 in boiling aqueous NaOH yielded 2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thiones 5 , the reaction in concentrated H2SO4 at room temperature gave 1,3,4‐thiadiazol‐2‐amines 6 . Similarly, the reaction of 1 with butyl isocyanate led to semicarbazides 7 , which, under basic conditions, undergo cyclization to give 2,4‐dihydro‐3H‐1,2,4‐triazol‐3‐ones 8 (Scheme 3). Treatment of 1 with Ac2O yielded the diacylhydrazine derivatives 9 exclusively, and the alternative isomerization of 1 to imidazol‐2‐ones was not observed (Scheme 4). It is important to note that, in all these transformations, the imidazole N‐oxide residue is retained. Furthermore, it was shown that imidazole N‐oxides bearing a 1,2,4‐triazole‐3‐thione or 1,3,4‐thiadiazol‐2‐amine moiety undergo the S‐transfer reaction to give bis‐heterocyclic 1H‐imidazole‐2‐thiones 11 by treatment with 2,2,4,4‐tetramethylcyclobutane‐1,3‐dithione (Scheme 5).  相似文献   

14.
An efficient one‐pot synthesis of 3‐[(4,5‐dihydro‐1H‐pyrrol‐3‐yl)carbonyl]‐2H‐chromen‐2‐one (=3‐[(4,5‐dihydro‐1H‐pyrrol‐3yl)carbonyl]‐2H‐1‐benzopyran‐2‐one) derivatives 4 by a four‐component reaction of a salicylaldehyde 1 , 4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one, a benzylamine 2 , and a diaroylacetylene (=1,4‐diarylbut‐2‐yne‐1,4‐dione) 3 in EtOH is reported. This new protocol has the advantages of high yields (Table), and convenient operation. The structures of these coumarin (=2H‐1‐benzopyran‐2‐one) derivatives, which are important compounds in organic chemistry, were confirmed spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this reaction is proposed (Scheme 2).  相似文献   

15.
Crystal Structures and Spectroscopic Properties of 2λ3‐Phospha‐1, 3‐dionates and 1, 3‐Dionates of Calcium ‐ Comparative Studies on the 1, 3‐Diphenyl and 1, 3‐Di(tert‐butyl) Derivatives A hydrogen‐metal exchange between dibenzoylphosphane and calcium carbide in tetrahydrofuran (THF) followed by addition of the ligand 1, 3, 5‐trimethyl‐1, 3, 5‐triazinane (TMTA) furnishes the binuclear complex bis[(tmta‐N, N′, N″)calcium bis(dibenzoylphosphanide)] ( 1a ) co‐crystallizing with benzene. Similarly, reaction of bis(2, 2‐dimethylpropionyl)phosphane with bis(thf‐O)calcium bis[bis(trimethylsilyl)amide] in 1, 2‐dimethoxyethane (DME) gives bis(dme‐O, O′)calcium bis[bis(2, 2‐dimethylpropionyl)phosphanide] ( 1b ) in high yield. The carbon analogues 1, 3‐diphenylpropane‐1, 3‐dione (dibenzoylmethane) or 2, 2, 6, 6‐tetramethylheptane‐3, 5‐dione (dipivaloylmethane) and bis(thf‐O)calcium bis[tris(trimethylsilylmethyl)zincate] in DME afford bis(dme‐O, O′)calcium bis(dibenzoylmethanide) ( 2a ) and the binuclear complex (μ‐dme‐O, O′)bis[(dme‐O, O′)calcium bis(dipivaloylmethanide)] ( 2b ), respectively. Dialkylzinc formed during the metalation reaction shows no reactivity towards the 1, 3‐dionates 2a and 2b . Finally, from the reaction of the unsymmetrically substituted ligand 2‐(methoxycarbonyl)cyclopentanone and bis(thf‐O)calcium bis[bis(trimethylsilyl)amide] in toluene, the trinuclear complex 3 is obtained, co‐crystallizing with THF. The β‐ketoester anion bridges solely via the cyclopentanone unit.  相似文献   

16.
The experimental 1H nuclear magnetic resonance (NMR) spectrum of 1H‐pyrazole was recorded in thermotropic nematic liquid crystal N‐(p‐ethoxybenzylidene)‐p‐butylaniline (EBBA) within the temperature range of 299–308 K. Two of three observable dipolar DHH‐couplings appeared to be equal at each temperature because of fast prototropic tautomerism. Analysis of the Saupe orientational order parameters using fixed geometry determined by computations and experimental dipolar couplings results in a situation in which the molecular orientation relative to the magnetic field (and the liquid crystal director) can be described exceptionally by a single parameter. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

17.
通过2-甲基-4-对甲苯基-1-苯甲酰基-2,3-二氢-1H-1,5-苯并二氮杂与由不对称1-苯基-2-偶氮-1,3-丁二酮热解产生的a-羰基烯酮的[2+4]环加成反应制备了标题化合物(C34H30N2O3,Mr=514.62),用X射线衍射测定了其单晶结构。晶体属单斜晶系,空间群为P21/n,a=11.560(1),b=19.058(3),c=13.207(2)A,β=106.82(1)°,V=2785.2(7)A3,Z=4,Dc=1.230g.cm-3,MoKa(λ=0.71073A),μ=0.064mm-1,F(000)=1088,2278个可观测衍子射点,R=0.046,Rw=0.049。分子骨架为由苯环、具有类扭船式构象的七元二氮杂环和略微扭曲的唑酮环构成的三环体系。  相似文献   

18.
NMR spectra of the synthesized azo dyes, 5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones (5a–g), 1,3‐dimethyl‐5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones (6a–g), and 5‐arylazo‐2‐thioxo‐pyrimidine (1H,3H,5H)‐4,6‐diones (7a–g) were studied in (CD3)2SO (three drops of CD3OD were added into solutions of the dyes in two different concentrations). All dyes showed intramolecular hydrogen bonding. Dyes 5a–7a showed bifurcated intramolecular hydrogen bonds. Tautomeric behaviours of some of N‐methylated azo dyes (6a‐g) were studied in two different concentrations. The solvent–substrate proton exchange of dyes 5a–d, 6a and 7a–e was examined in presence of three drops of CD3OD. The dyes which were soluble in (CD3)2SO containing CD3OD showed isotopic splitting (β‐isotope effect) in the 13C NMR spectra. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

19.
Several quinazoline‐2(1H),4(3H)‐dione derivatives were synthesized from pyrimidine‐2(1H),4(3H)‐dione derivative.  相似文献   

20.
The reaction of 1,4,5‐trisubstituted 1H‐imidazole‐3‐oxides 1 with 2,2‐bis(trifluoromethyl)ethene‐1,1‐dicarbonitrile ( 7 , BTF) yielded the corresponding 1,3‐dihydro‐2H‐imidazol‐2‐ones 10 and 2‐(1,3‐dihydro‐2H‐imidazol‐2‐ylidene)malononitriles 11 , respectively, depending on the solvent used. In one example, a 1 : 1 complex, 12 , of the 1H‐imidazole 3‐oxide and hexafluoroacetone hydrate was isolated as a second product. The formation of the products is explained by a stepwise 1,3‐dipolar cycloaddition and subsequent fragmentation. The structures of 11d and 12 were established by X‐ray crystallography.  相似文献   

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