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1.
1,1,4,4-Tetranitrobutane-2,3-diol reacts with formaldehyde, forming 2,2-dinitropropane-1,3-diol or a cyclic ether — 4,4-dinitro-2,3-dihydroxytetrahydrofuran — as a function of the reaction conditions.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2755–2759, December, 1992.  相似文献   

2.
A two-step synthesis has been proposed to obtain 1,12-difluoro-1,1,3,5,5,8,8,10,12,12-decanitro-3,10-diazadodecane-6,7-diol dinitrate, starting from 1,1,4,4-tetranitrobutane-2,3-diol and N-(methoxymethyl)-2-fluoro-2,2-dinitroethyl-amine, followed by nitration of the Mannich base formed. An x-ray-diffraction investigation of the dinitrate obtained was carried out.Insitute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 671–675, March, 1992.  相似文献   

3.
The bromination of 1,1,4,4-tetranitrobutane-2,3-diol in 60% acetic acid gave 1,4-dibromo-1,1,4,4-tetranitrobutane-2,3-diol in satisfactory yield. The chlorination of 1,1,4,4-tetranitrobutane-2,3-diol under analogous conditions gave 1,4-dichloro-1,1,4,4-tetranitrobutane-2,3-diol as a crystal hydrate. Drying of this latter product in vacuum over phosphorus pentoxide gave 1,4-dichloro-1,1, 4,4-tetranitrobutane-2,3-diol in quantitative yield. The structures of these products were determined by x-ray diffraction structural analysis. The crystal chemical analysis and quantum chemical calculations established an increase in secondary oxygen-halogen interactions in the halodinitromethyl fragment with increasing atomic number of the halogen atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2372–2380, October, 1991.  相似文献   

4.
The synthesis of 1,1,4,4-tetranitrobutane-2,3-diol has been carried out via the reaction of the dinitromethane potassium salt with glyoxal, at pH values of 7–8 after reagent mixing and 5.5 at the end of the reaction, in the temperature range 35–37°C. X-ray crystal structure analysis has been performed on 1,1,4,4-tetranitrobutane-2,3-diol and its diacetate. The conformations of these molecules are stabilized to a significant extent by O...N+-type electrostatic interaction, which was confirmed by quantum-mechanical calculations on 2,2-dinitroethanol as a model molecule.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 830–834, April, 1991.  相似文献   

5.
研究了一种关于meso-四苯基-2,3-二氢卟啉-2,3-二醇的避免使用昂贵且剧毒的四氧化锇的合成方法,整个合成过程中所用试剂廉价易得,反应操作简单.该合成方法可同时得到顺、反两种目标产物异构体.  相似文献   

6.
New procedures were developed for the synthesis of 3,3-bis(hydroxymethyl)oxetane dinitrate (1) by O-nitration of the corresponding glycol (3) or its mononitrate (6), which were prepared by the reactions of 2,2-bis(hydroxymethyl)propane-1,3-diol (pentaerythritol) (2) mono- (4) and dinitrates (5), respectively, with alkali. A new method was devised for the synthesis of compounds 4 and 5 by the reaction of tetraol 2 with concentrated HNO3 in dichloroethane. The structures of compounds 1 and 6 were established by X-ray diffraction analysis.  相似文献   

7.
A synthetic approach to novel derivatives of dihalonitroethenes, methyl and ethyl 2,3-dibromo-3-nitroacrylates, was developed and their structures were investigated. X-ray single crystal analysis demonstrated that ethyl 2,3-dibromo-3-nitroacrylate had Z-configuration. The steric strain in this molecule is released mainly due to withdrawal of the ester group from the C=C double bond plane.  相似文献   

8.
A new method for the synthesis of 2,3-diamino-1,4-dimethoxyanthraquinone from quinizarin has been developed. Heterocyclic analogs of 5,12-naphthacenequinone have been synthesized based on this o-diamine-4,11-dimethoxyanthra[2,3-d]imidazole-5,10-dione, 4,11-dimethoxyanthra[2,3-d][1,2,3]triazole-5,10-dione, and 5,12-dimethoxynaphtho[2,3-g]quinoxaline-6,11-dione. On the 70th Birthday of Professor E. Lukevics. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No.1, 96–102, January 2007.  相似文献   

9.
Ikuko Ueda 《Tetrahedron letters》2006,47(48):8535-8537
Reaction of 2,3-dibromo-1-methylindole with tert-butyllithium at −78 °C followed by treatment with tropylium ion gave 2-bromo-3-cycloheptatrienyl-1-methylindole in a moderate yield, indicating that 2-bromo-3-lithio-1-methylindole would be involved as an intermediate instead of 3-bromo-2-lithio-1-methylindole. The structure of 2-bromo-3-cycloheptatrienyl-1-methylindole was unequivocally determined by a single X-ray analysis. 2,3-Diiodo-1-methylindole also gave a 3-lithio derivative exclusively.  相似文献   

10.
Peng Wu 《合成通讯》2013,43(1):70-84
A series of novel 1,4-benzoxazine-2,3-dicarboximides starting from maleic anhydride and substituted aromatic amines were synthesized.  相似文献   

11.
The interaction of 5-aryl-4-quinoxaline-2,3-dihydro-2,3-furandiones with mesitylamine and methyl(phenyl) hydrazine results in the formation of 1-substituted 5-aryl-4-quinoxalinyl-2,3-dihydro-2,3-pyrrolediones. The crystal and molecular structure of the 1-mesityl-5-phenyl derivative was investigated by X-ray diffraction.Original Russian Text Copyright © 2004 by Z. G. Aliev, N. Yu. Lisovenko, L. O. Atovmyan, and A. N. MaslivetzTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 553–557, May–June 2004.  相似文献   

12.
《Tetrahedron letters》1988,29(15):1833-1836
The two title compounds (1,2) have been prepared and some Diels-Alder reactions investigated.  相似文献   

13.
By treating with phosphorus pentoxide the 4,5-dichloroisothiazole-3-carboxamide 4,5-dichloro-3-cyanoisothiazole was synthesized whose reactions with piperidine, phenyl-and benzylthiols occurred with replacement of the chlorine atom in the position 5 by the residue of the corresponding nucleophile. Reactions with sodium thiobytylate and also with sodium methylate in methanol led to the formation both of the products of chlorine substitution by BuS or MeO groups respectively and of addition products of methanol to the cyano group. The reaction of butanethiol with cyanoisothiazole in 2-propanol in the presence of sodium 2-propylate was more selective and resulted in the replacement of the chlorine atom in the position 5 by the residue of the butanethiol.  相似文献   

14.
A series of fully aromatic, thermotropic polyesters based on 1,1′-binaphthyl-4,4′-diol, BND, was prepared by the melt polycondensation method and characterized for their thermotropic behavior by a variety of experimental techniques. The homopolymer of BND with terephthalic acid formed a nematic melt at 353°C. In contrast, the polyester from BND and 2,6-naphthalenedicarboxylic acid had a melting transition, Tm, above 400°C, so it was not possible with the equipment available to determine whether it formed a nematic melt. All of the copolymers of BND formed nematic melts at much lower Tm values than those of its respective homopolymers, as expected, because of the copolymerization effect of the added monomer. Moreover, all of the copolymers had higher glass transition temperatures, Tg, than those of other liquid crystalline polyesters and higher thermal stabilities. © 1994 John Wiley & Sons, Inc.  相似文献   

15.
An X-ray structural investigation of 6-chloro- 2,3-trimethylene-4- phe nylquinoli ne obtained by the reaction of 2-amino-5-chlorobenzophenone with cyclopentanone was carried out. At 20 °C, a = 23.750,b = 9,242, c = 14.018 A, = 112,68° space group (21c,Z = 8, 2647 reflections,R = 0.047 He five-membered ring has an envelope conformation Conjugation between the quinohne fragment and the phenyl substituent is significantly distorted dm to the rotation of the latter by -62.9°Translated fromIzvestiya Akademii Nauk. Seriva Khimicheskaya, No. 7, pp. 1800–1802, July, 1996.  相似文献   

16.
1-Unsubstituted 4,5-diphenyl-2,3-dihydro-2,3-pyrroledione interacts with ethoxycarbonyl-methylenetriphenylphosphorane regioselectively to give 4,5-diphenyl-Z-2-ethoxycarbonyl-methylene-2,3-dihydro-3-pyrrolone. The crystal and molecular structure of the latter was studied by X-ray analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1556–1558, August, 1995.  相似文献   

17.
梁长海  刘倩  李闯  陈霄 《分子催化》2013,27(4):316-322
采用化学还原法合成Pd纳米立方体,并将其作为晶种,进一步合成大尺寸的纳米Pd立方体以及具有不同{100}和{111}晶面比例的纳米Pd多面体.将形貌和尺寸可控的纳米Pd溶胶应用于1,4-丁炔二醇催化加氢的反应中,反应结果表明,纳米Pd的催化性能取决于其尺寸和形貌.{111}晶面的催化活性高于{100}晶面,PVP稳定的Pd胶体对1,4-丁烯二醇均具有较高选择性,具有适当{100}和{111}晶面比例的纳米Pd多面体对1,4-丁烯二醇的选择性可达96%.  相似文献   

18.
A versatile new approach for the synthesis in three steps of 2-substituted-2,3-dihydro[1,4]dioxino[2,3-b]pyridines B via a Smiles rearrangement using easily available reagents is described. A study illustrating the influence of experimental conditions on the progress of the reaction is reported.  相似文献   

19.
The first simple cyclic silyl peroxide, namely 1,1,4,4,-tetramethyl-1,4-disila-2,3-dioxane (1), was prepared by classical synthetic methodology from its corresponding cyclic disilazane and the urea complex of hydrogen peroxide.  相似文献   

20.
Allylmetallation of isoquinolines, quinoline, and quinoxaline with allylic derivatives of zinc was examined for the first time. A convenient procedure was discovered and developed for the synthesis of 1,4-ethano-2,3-dihydroisoquinolines based on the reactions of isoquinolines with allylic derivatives of zinc. This multistage process involves double allylmetallation of the heterocyclic ring followed by cyclization through intramolecular carbometallation of the C=C bond. The structures of three key derivatives of 1,4-ethano-2,3-dihydroisoquinoline were established by X-ray diffraction analysis. The reactions of quinoxaline with allyl- and methallylzinc bromide proceeded stereospecifically to form trans-2,3-diallylated 1,2,3,4-tetrahydroquinoxalines. Heating of quinoline with methallylzinc bromide in THF afforded 4-methallylquinoline in nearly quantitative yield. The initially formed 1,4-metallation product underwent aromatization through elimination of HZnBr.  相似文献   

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