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1.
The direction of the reaction of 4-methoxy-1-benzopyrylium salts and their 1-thia and 1-selena analogs with methylene bases formed from methyl-substituted heterocyclic onium salts is qualitatively determined by the nature of the heteroatom. In contrast to the 4-methoxy-1-benzopyrylium salt, which reacts with a nucleophilic agent primarily in the 2 position with cleavage of the O-C bond, the 4-methoxy-1-benzothiapyrylium salt condenses at the 4 position, whereas the 4-methoxy-1-benzoselenapyrylium salt undergoes oxidative condensation at the 2 position. All of the salts react in the same way with dimethylaniline with oxidative condensation at the 2 position.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 178–181, February, 1977.  相似文献   

2.
[reaction: see text] N-Alkyl-4-boronopyridinium salts are highly effective and reusable catalysts for the dehydrative amide condensation reaction between equimolar mixtures of carboxylic acids and amines. N-Alkylboronopyridinium salts are thermally stabilized in the order N-alkyl-2-boronopyridinium salt < N-alkyl-3-boronopyridinium salt < N-alkyl-4-boronopyridinium salt. Homogeneous catalysts, such as 4-borono-N-methylpyridinium iodide, are more effective in the presence of ionic liquid and can be recovered by extraction with ionic liquid. In contrast, heterogeneous catalysts, such as polystyrene-bound 4-boronopyridinium salts, are effective even in the absence of ionic liquid and can be recovered by filtration.  相似文献   

3.
With urea 1,5-diaryl-3-hydroxy-4-methylsulfonyl-3-pyrrolin-2-ones form the 3-amino derivatives of pyrrolones. In reactions with hydrazine hydrate and ethylenediamine the corresponding salts are formed. With ethylenediamine at 180–185°C the double salt of 3-hydroxy-4-methylsulfonyl-1,5-diphenyl-3-pyrrolin-2-one forms N,N′-di(4-methylsulfonyl-1,5-diphenyl-3-pyrrolin-2-on-3-yl)-ethylenediamine. The reaction with o-phenylenediamine gives 2,3-diaryl-4-methylsulfonylpyrrolo-[2,3-b]quinoxalines. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, 1631–1636, November, 2007.  相似文献   

4.
The reactions of 4-ethoxychromylium salts with some amines were studied. It was shown that o-hydroxyarylpyrazoles and chromone phenylhydrazones, respectively, are formed by the reaction of these salts with hydrazine and phenylhydrazine. The action of primary aromatic amines leads to replacement of the 4-ethoxy group by a 4-arylamino group, while the reaction of the 4-ethoxychromylium salts with N,N-diethylaniline gives 4-ethoxy-4-diethylaminoflavylium salts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1112–1114, August, 1971.  相似文献   

5.
Taraba J  Zak Z 《Inorganic chemistry》2006,45(9):3695-3700
Several salts of bis(chlorosulfonyl)imide HN(SO2Cl)2 (1), namely, two solvates of its potassium salt, KN(SO2Cl)2.(1/2)CH3CN (1K1), KN(SO2Cl)2.(1/6)CH2Cl2 (1K2), and its tetrachlorophosphonium salt, [PCl4][N(SO2Cl)2] (2), were prepared and structurally characterized. The reaction of HN(SO2Cl)2 with Me3N gives the [N(SO2Cl)2]- salt of a novel cation, [N(SO2NMe3)2]+. This cation is analogous to the [HC(SO2NMe3)2]+ cation, but in contrast to the latter, it is fairly stable to hydrolysis. The salt [N(SO2NMe3)2]+[N(SO2Cl)2]- (3) can be converted into salts of other anions by being treated with diluted aqueous solutions of the respective acids, and thus NO3-, Cl-.H2O, SeO3(2-), CH3COO-, HSO4-, (COO)2(2-) salts were prepared. Treatment of 3 with concentrated HNO3 gave the [N(SO2NMe3)2]+ [O2NO-H-ONO2]- salt, and the addition of an HCl-acidified FeCl3 aqueous solution yielded the FeCl4- salt. Methanolysis resulted in the formation of MeOSO3- and [MeOSO2NSO2OMe]- salts. All salts have been characterized by chemical analysis, vibrational spectroscopy, and X-ray structure determinations.  相似文献   

6.
The studies of the condensation of 4-nitrosemicarbazide (4-NSC) with various aldehydes and ketones resulted in the development of an approach to the synthesis of N-nitrosemicarbazones, promising high-energy and biologically active compounds. Subsequent treatment with amines and alkalis led to the synthesis of water-soluble salts of nitrosemicarbazones, as well as the corresponding semicarbazones. The reaction of N,N′-diisopropyl- or N,N′-di-tert-butyl-1,2-ethanediimine with 4-nitrosemicarbazide led to the synthesis of glyoxal bis(nitrosemicarbazone) derivatives. A computer-aided screening using the PASS software showed a probability of high biological activity for the compounds obtained, whereas antiarrhythmic properties of camphor nitrosemicarbazone potassium salt were confirmed in experiments in rats.  相似文献   

7.
Regiospecific introduction of the 2-naphthyl residue into position 4 of the pyridine ring occurs in the reactions of isoquinolinium salts with 4-methylpyridinium salts through the intermolecular transformation of the isoquinoline bicyclic system involving the methyl group of the pyridinium salt. The reaction occurs under the action of methylammonium sulfite in an aqueous medium on heating. This method provides ring transformation not only for isoquinolinium salts but even for unsubstituted isoquinoline.  相似文献   

8.
聚苯砜醚是一种综合性能比较好、可在180℃长期使用的热塑性工程塑料,在国内外受到一定的重视。我们与武汉化工原料厂协作,对4-氯-4′-羟基二苯砜钾盐真空熔融缩聚合成聚苯砜醚的途径进行过一些探索,得到了较好的结果。但是,在实践中发现,由于这一反应速度快,放出的热量大而集中,在真空中聚合热不易导出,随着单体用量  相似文献   

9.
Mutoh Y  Murai T 《Organic letters》2003,5(8):1361-1364
[reaction: see text] A variety of selenoiminium salts were obtained by reacting the corresponding selenoamides with methyl triflate at room temperature for 30 s. All of the salts were stable under air. The structures of the selenoiminium salts were determined by X-ray molecular analysis. An aromatic selenoiminium salt reacted with BuLi (3 equiv) to give two types of ketones. In a reaction with LiAlH(4)/Te, the selenoiminium salts were converted to telluroamides.  相似文献   

10.
4-Aryl-4-phosphono-β-lactams are prepared by acylation of iminium salts with chloroacetyl chloride followed by phosphite addition and ring closure using sodium hydride as a base. Deacylation of the iminium salt is in competition with the desired addition of phosphites to acyliminium salts, which lowers the yield of the reaction.  相似文献   

11.
The reaction of substituted 3-cinnamoyl-4-hydroxycoumarins with pyridinium salts of various bromomethyl ketones gives the corresponding 4-hydroxy-3-pyridylcoumarins. The use of microwave radiation decreases the time required and improves the yield of this reaction. The products obtained do not display solvatochromic properties or photochemical activity.  相似文献   

12.
The Vilsmeier reaction of 3-nitropyrroles which are prepared by the reaction of nitroalkenes with the sodium salt of tosylmethylisocyanide gives 2-formyl-4-nitropyrroles in good yields.  相似文献   

13.
Treatment of imidazo[4, 5-f]quinoline and some of its 3-substitmion products with methyl halides and methyl benzenesulfonate gives as the main reaction products N-methylimidazoquinolinium salts, which can also be synthesized from 5, 6-dimainoquinolines. Methylation at the N atom of the imidazole ring is only a side reaction. Treatment with trimethylphenylammonium hydroxide introduces a methyl radical into the NH group of imidazoquinoline, giving a mixture of 1-and 3-substitution products.  相似文献   

14.
3-Cyclopropyl-3-oxopropionitrile anion obtained by cathodic reduction of 5-cyclopropylisoxazole in an aprotic medium was used as an example to demonstrate that cyano ketone anions show a dual reactivity. The reaction of acetyl chloride with the electrogenerated tetrabutylammonium salt of 3-cyclopropyl-3-oxopropionitrile gave O-acylation products, whereas the reaction with its sodium salt gives C-acylation products. The reactions of these salts with hydroxylamine hydrochloride follow a different route: in the case of the tetrabutylammonium salt, resinification takes place, while in the case of the sodium salt, 5-amino-3-cyclopropylisoxazole is formed. The condensation of this product with 4,4,4-trifluoro-1-(2-thienyl)butane-1,3-dione in glacial AcOH affords 3-cyclopropyl-6-(2-thienyl)-4-(trifluoromethyl)isoxazolo[5,4-b]pyridine in 85% yield. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2110–2114, November, 2007.  相似文献   

15.
The annulation reaction of vinamidinium salt containing nitrofurazanyl moiety at the β‐position gives access to the corresponding pyrazole. At nitration, two nitro groups were installed to the pyrazole ring. The synthesized 3‐(3,5‐dinitropyrazol‐4‐yl)‐4‐nitrofurazan 13 is strong NH acid and a new family energetic salts was prepared by direct neutralization with high nitrogen bases. Compound 13 crystallizes in the monoclinic space group P21/c, and charaterized by high density of 1.979 g/cm3 (at 100 K). J. Heterocyclic Chem., (2012).  相似文献   

16.
二苯胺型重氮树脂是阴图PS版最重要的感光剂[1],关于它的应用已有许多专利[2 5].作为一种预涂感光版,阴图PS版的贮存期要求在一年以上,从而对作为感光剂的重氮树脂的热稳定性有较高的要求,希望其热分解温度尽量高一些并能在潮热气候下性质稳定.一般来说,二苯胺重氮盐的苯环上带取代基时,有利这些性质的改善,如3-甲氧基二苯胺-4-重氮盐树脂就是一个例子,它已获得广泛的应用[6,7].  相似文献   

17.
A quaternary salt of 4-(diethylamino)butan-2-one, methyldiethyl-3-ketobutylammonium methyl sulfate, is used as an alkylating agent to synthesize lepidine and 1-phenyllepidine salts. The method gives good yields, under mild conditions, of lepidine and 1-phenyllepidine perchlorate. An intermediate product is isolated, and a reaction mechanism suggested.  相似文献   

18.
The reactivity of CO(2) with polyamino substrates based on calix[4]arenes and on a difunctional, noncyclic model has been studied. All the compounds react with CO(2) in chloroform to form ammonium carbamate salts. However, the number, topology, and conformational features of the amino-functionalized arms present on the multivalent scaffold have a remarkable influence on the reaction efficiency and on the product composition. Tetraaminocalix[4]arenes 1-3 rapidly and efficiently react with 2 equiv of CO(2), yielding highly stable hydrogen-bonded dimers formed by the self-assembly of two bis-ammonium bis-carbamate intramolecular salts. 1,3-Diaminocalix[4]arene 4 absorbs 1 mol of CO(2), affording less stable zwitterionic ammonium carbamates. Gemini compound 5 reacts with CO(2) in a 1:1 stoichiometry, forming hydrogen-bonded dimers of ammonium carbamate derivatives of moderate stability. For upper rim 1,3-diaminocalix[4]arene 6, in addition to the labile intramolecular salt, the presence of a self-assembled polymer was also detected. These systems were fully characterized in solution by (1)H and (13)C NMR spectroscopy, whereas the corresponding gas-solid reactions were further investigated by QCM measurements. Interestingly, the high affinity and reversibility of CO(2) uptake shown by 1,3-diamino calix[4]arene 4 enabled us to attain a promising QCM device for carbon dioxide sensing.  相似文献   

19.
The reaction of 4-methoxybenzylideneiminium salts with methylamine and dimethylamine on heating results in replacement of the MeO group by an alkylamino-group, whereas the reaction with piperidine affords 3,5-bis-(4-methoxybenzyl)pyridine. N-Methyl-2-(4-methoxyphenyl)pyridinium iodide on treatment with methylamine undergoes dealkylation to the arylpyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1226–1229, September, 1990.  相似文献   

20.
Reaction of 2-thiono-1, 3-thiazan-4-one (I) with phosphorus pentasulfide in dry dioxane gives an 81% yield of the hitherto unknown 2, 4-dithiono-1, 3-thiazane (II), which differs from the starting compound by having reactive groups at positions 4 and 5. The 5-substituted products of condensing II with diazonium salts and dimethylaminobenzaldehyde, and the products of reaction of II with aminoantipyrine and a number of aromatic amines are isolated. The irritating effect of II on the mucous membrane, and its bringing about increased sensitivity to certain cations are noted. Qualitative reactions for detecting II are suggested.For Part I see [9].We thank Professor S. N. Baranov for his interest in our work.  相似文献   

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