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1.
Methods for the synthesis of substituted bis(2,5-dimethyl-3-thienyl)ethenes with 1,3-dioxole- and 1,3-oxazole-2-thione fragments as ethene bridges were developed. These compounds exhibit photochromic properties. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1299–1301, May, 2005.  相似文献   

2.
Two general procedures were developed for the synthesis of chiral N-mono-, N, N′-di-, N, NN″-tri-, and N, N′, N″, N′″-tetraalkylglycolurils based on the reactions of 4,5-dihydroxy-imidazolidin-2-ones or glyoxal with one or two moles of alkylureas, respectively, by acid catalysis. The reactions of N-monoalkyl- and N, N′-dialkylureas with glyoxal proceed regioselectively. The mechanism of these reactions was suggested and partly confirmed by quantum-chemical calculations and experimental data. The enantiomeric separation of some chiral glycolurils by chiral-phase HPLC was carried out for the first time.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 680–692, March, 2005.  相似文献   

3.
Two-step α-ureidoalkylation of ureas with various 4,5-dihydroxyimidazolidin-2-ones gave novel 1,3-dialkyl-4,5-bis(3-alkylureido)-, 1,3-dialkyl-4,5-bis[3-(2-pyrimidyl)ureido]-, or 1,3-dialkyl-4,5-bis(3,3-dialkylureido)imidazolidin-2-ones and ensembles of three imidazolidine rings. The structure of 4,5-bis(2-oxoimidazolidin-1-yl)imidazolidin-2-one was confirmed by X-ray diffraction data. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 140–145, January, 2007.  相似文献   

4.
Metall(II) bis-chelates of 1,3-dithiole-2-thione-4,5-dithiolate (dmit) and 1,2-dithiole-3-thione-4,5-dithiolate (dmt) undergo in CHCl3/CH3CN (ratio 1:24) photooxidation to the metal(III) bis-chelates when irradiated at 313 nm. No side reactions were observed. There is no correlation between the quantum yields of photooxidation and the electrochemical halve-wave potentials. This holds also in comparison to maleonitriledithiolato chelates.  相似文献   

5.
4,5-Dichloro-2-dicyanomethylene-4-cyclopenten-1,3-dione (2) is synthesized by partial Retro-Michael addition of tetracyanoethylene to 4,5-dichloro-4-cyclopentene-1,3-dione. Compound2 is a new electron acceptor, withN-methyl-benzthiazolone-2-hydrazone giving a charge-transfer complex (6). Nucleophilic substitution of2 by pyrrolidine, morpholine and piperidine leads to deeply coloured bisamides7,8. With aromatic amines bisamides are formed too (11), but monosubstitution products can be isolated.N,N-Dimethylaniline reacts with2 by elimination of hydrogen chloride, leading to aN,N-dimethylaminophenyl monosubstitution product of2. The bisamides are green-blue compounds with intense violet colour in solution. The dyes can be classified as pseudooxo croconic acid bisamides, the new type of chromophore is discussed by13C-spectroscopy and quantum chemical calculations (CNDO-CI).
Herrn Prof. Dr.E. Ziegler zum 70. Geburtstag gewidmet.  相似文献   

6.
The reaction of 4-bromo-1,3-diphenyl-2-buten-1-one with thiourea or N,N′-diphenylthiourea gives 2-(2-amino-4-phenyl-4,5-dihydro-1,3-thiazol-4-yl)-and 2-[3,4-diphenyl-2-(phenylimino)-1,3-thiazolidin-4-yl]-1-phenyl-1-ethanone — the products of nucleophilic substitution of the halogen atom and Michael addition at position 3 of the 2-buten-1-one system. A similar reaction with thiosemicarbazide and 1-phenylthiosemicarbazide gives the 4-(2-oxo-2-phenylethyl)-4-phenyl-and 4-(2-oxo-2-phenylethyl)-3,4-diphenyl-1,3-thiazolidin-2-one hydrobromides respectively. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 103–110, January, 2008.  相似文献   

7.
The reactions of 1,3-dialkyl-4,5-dihydroxyimidazolidin-2-ones with alkyl sulfamides have been studied and previously undescribed 1,3-dialkyl-4-(alkylaminosulfonylimino)imidazolidin-2-ones have been obtained. The structure of 1,3-dimethyl-4-(benzenesulfonylimino)imidazolidin-2-one was investigated by X-ray structural analysis. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1159–1166, August, 2007.  相似文献   

8.
Procedures were developed for the synthesis of substituted bis(2,5-dimethyl-3-thienyl)ethenes containing the imidazol-2-one, 1,3-dioxol-2-one, or 1,3-oxazol-2-one fragments as ethene bridges. These compounds were demonstrated to exhibit the photochromic properties. The cyclic forms of some imidazolone and oxazolone photochromes possess high thermal stability. The structure of photochromic 4,5-bis(4-acetyl-2,5-dimethyl-3-thienyl)-3-methyl-2,3-dihydro-1,3-oxazol-2-one was established by X-ray diffraction analysis. The molecule adopts an anti-parallel conformation similar to that of perfluorocyclopentene-bridged dithienylethenes.  相似文献   

9.
Direct fluorination of 1,3-dioxolan-2-one with elemental fluorine was successfully carried out to provide 4-fluoro-1,3-dioxolan-2-one, which was expected as an additive for lithium ion secondary battery. 4-Fluoro-1,3-dioxolan-2-one was also further fluorinated with elemental fluorine to give three isomers of difluoro derivatives by the same methodology. Another topic is the preparation of trifluoromethanesulfonyl fluoride, an intermediate of lithium battery electrolyte, by the reaction of methanesulfonyl fluoride with elemental fluorine. The use of perfluoro-2-methylpentane as a solvent gave satisfactory selectivity of trifluoromethanesulfonyl fluoride.  相似文献   

10.
azo[4,5-e][1,2,4]triazin-6-ones, 4,5-bis(3-thiosemicarbazido(guanidinoamino))imidazolidin-2-ones, and 1,3-dialkyl-4-(guanidinoimino)imidazolidin-2-ones by α-ureidoalkylation of thiosemicarbazide or aminoguanidine were found. A novel conglomerate in the series of imidazolidin-2-one derivatives was detected: 4,5-bis(guanidinoamino)-1,3-dimethylimid-azolidin-2-one dihydrochloride dihydrate. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 836–843, May, 2006.  相似文献   

11.
The interaction of sulfonamides with 4,5-dihydroxyimidazolidin-2-ones was studied for the first time. The earlier unknown 4,4′-sulfonyldiiminobis(1,3-dialkylimidazolidin-2-ones) and 4(5)-aryl(alkyl)-sulfonyliminoimidazolidin-2-ones were synthesized. A probable pathway of the reaction was proposed. 1,3-Diethyl-4,5-dihydroxyimidazolidin-2-one was isolated and described. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1604–1607, August, 1998.  相似文献   

12.
Summary 1,3-Dialkyl-4,5-imidazolidinediones (5) were prepared by the reaction of oxalyl chloride (3) with the corresponding 1,3,5-trialkyl-hexahydro-1,3,5-triazines (4), followed by addition of ethanol, in good to fair yields and fully characterized by MS, IR,1H and13C NMR.
Heterocyclen aus Heterocyclen: 1,3-Dialkyl-4,5-imidazolidindione aus 1,3,5-Trialkyl-hexahydro-1,3,5-triazinen und Oxalylchlorid
Zusammenfassung Durch die Reaktion von Oxalylchlorid (3) mit den entsprechenden 1,3,5-Trialkyl-hexahydro-1,3,5-triazinen (4) und anschließender Ethanolzugabe wurden 1,3-Dialkyl-4,5-imidazolidindione (5) in zufriedenstellenden bis guten Ausbeuten hergestellt. Die Produkte wurden mit spektroskopischen Methoden charakterisiert.
  相似文献   

13.
The 2‐thienyl‐substituted 4,5‐dihydrofuran derivatives 3 – 8 were obtained by the radical cyclization reaction of 1,3‐dicarbonyl compounds 1a – 1f with 2‐thienyl‐substituted conjugated alkenes 2a – 2e by using [Mn(OAc)3] (Tables 15). In this study, reactions of 1,3‐dicarbonyl compounds 1a – 1e with alkenes 2a – 2c gave 4,5‐dihydrofuran derivatives 3 – 5 in high yields (Tables 13). Also the cyclic alkenes 2d and 2e gave the dihydrobenzofuran compounds, i.e., 6 and 7 in good yields (Table 4). Interestingly, the reaction of benzoylacetone (=1‐phenylbutane‐1,3‐dione; 1f ) with some alkenes gave two products due to generation of two stable carbocation intermediates (Table 5).  相似文献   

14.
The paper reviews data on the synthesis of heterocyclic compounds with perfluoroalkyl groups based on the reaction of thiocyanate and isothiocyanate derivatives of perfluoroolefins with mononucleophilic reagents (C-, O-, S-, P-, and N-nucleophiles). It was shown that such derivatives are prospective synthons for the production of 1,3-thiazoles and 1,3-thiazolines. The factors affecting the formation of the heterocyclic system are identified.  相似文献   

15.
We have obtained 5-(2-pyridyl)[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione for the first time by cycloaddition of 2-ethynylpyridine to 4,5-dihydro-1,3-dithioltrithione (isotrithionedithiol). We have studied this thione, 5-(2-pyridyl)- and 5-(4-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thiones by mass spectroscopy and also IR, UV, 1H and 13C NMR spectra. We have determined the crystal and molecular structure of 5-(2-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 429–434, March, 2005.  相似文献   

16.
4,5-Decamethyleneimidazole, 4,5-decamethyleneoxazole, and 4,5-decamethyleneimidazolone-2 were synthesized by reactions of 2-bromocyclododecanone and 2-hydroxycyclododecanone with formamide, ammonium formate, and urea, respectively. Condensation of 2-formylcyclododecanone with hydroxylamine and hydrazine hydrate resulted in 4,5-decamethyleneisoxazole, and 4,5-decamethylenepyrazole, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 891–893, May, 1994.  相似文献   

17.
Abstract

Nous décrivons la synthèse en quatre étapes de nouveaux 1,3-dihydrobenzodiazaphospholes 3 et 6a-c dont la particularité est de posséder un (3) ou deux (6a-c) motifs N-acyl-diazaphospholines. Seuls les ligands 6a-c présentent des propriétés complexantes vis-à-vis des ions alcalino-terreux. observables par spectrométrie IR et UV.

We describe a four step synthesis of new 1,3-dihydrobenzodiazaphospholes 3 and 6a-c which posses one (3) or two (6a-c) N-acyl diazaphospholine moieties. Only the formation of alkaline-earth cation complexes, with 6a-c has been observed by IR and UV spectroscopies.  相似文献   

18.
Ligand Exchange on Bis(1,3-diselenole-2-selone-4,5-diselenolato)cuprate(II) ([Cu(dsis)2]2?) with CuII Four and Five Ring Bis-chelates Containing Unsaturated Vicinal and Geminal Dichalcogeno Ligands. An EPR Study Ligand exchange reactions (“chelate metathesis”) of bis(1,3-diselenole-2-selone-4,5-diselenolato)cuprate(II), ([Cu(dsis)2]2?, with other CuII four- or five-ring chelates of unsaturated dichalcogeno ligands are reported. The small solubility of salts of the title complex in common solvents like acetone or chloroform requires pyridine. Mixed-ligand complexes could be detected for all combinations of two starting complexes studied by means of their go and aoCu (EPR) parameters. Due to the coordinating properties of pyridine and electronic reasons commonly used linear dependences of the g value from the composition of the first coordination sphere (“additivity rules”) are not applicable.  相似文献   

19.
An innovative synthesis of aryl tethered 1,3-dimethylimidazo[4,5-b]pyrazin-2-ones 4 and 6 has been delineated through base catalyzed ring transformation of 6-aryl-4-(piperidin-1-yl)-2H-pyran-2-one-3-carbonitriles 1 and methyl 6-aryl-4-methylsulfanyl-2H-pyran-2-one-3-carboxylates 5 with 7-acetyl-1,3-dimethyllumazine 2 with subsequent ring contraction of the fused pyrimidine to an imidazole ring. An additional product, methyl [6-(1,3-dimethyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyrazin-5-yl)-4-thiophen-2-ylpyran-2-ylidene]acetate 8b, was also isolated from the reaction of 5 and 2, as a minor constituent.  相似文献   

20.
A base-free catalyst system Co(acac)3/BMMImCl was developed for the carbonylation of amines with CO2. 45%\2-81% isolated yields for N,N-dialkylureas and 6%\2-23% isolated yields for N,N-diarylureas were obtained. The catalyst system was recovered and reused without significant loss in activity. In this catalyst system, the base catalyst and chemical dehydrant were efficiently avoided. Different reaction conditions were also discussed and a postulated mechanism was proposed.  相似文献   

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