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1.
Bromination, acylation, nitration, and metallation of imidazole and pyrrole derivatives containing the difluoromethylene fragment at the N atom were studied. 1-(1,1,2,2-Tetrafluoroethyl)pyrrole, 1-(1,1,2,2-tetrafluoroethyl)imidazole, and 1-(2-chloro-1,1,2-trifluoroethyl)imidazole were used as substrates. 1-Alkyl-3-(1,1,2,2-tetrafluoroethyl)- and 1-alkyl-3-(2-chloro-1,1,2-trifluoroethyl)imidazolium iodides were obtained. These can be used as intermediates for preparation of new ionic liquids of the imidazole series and 1-alkyl-3-polyfluoroethylimidazole-2-thiones.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 781–787, March, 2005.  相似文献   

2.
It was shown by electron absorption spectroscopy and X-ray diffraction analysis that steric strains in photochromic 2-(N-acyl-N-arylaminomethylene) benzo[b]thiophen-3(2H)-one molecules ortho-substituted in the N-phenyl ring increase the quantum yield of the N→O photoinduced rearrangement in accord with an increase in the steric constant of the ortho-substituent.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2151–2155, October, 2004.  相似文献   

3.
A synthesis is reported for (4R,5R)-and (4S,5S)-4-hydroxymethyl-5-(4-nitrophenyl)oxazolidin-2-ones and (1′R,4R)-and (1′S,4S)-4-[hydroxy(4-nitrophenyl)methyl]oxazolidin-2-ones from (1R,2R)-and (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediols. The effect of the experimental conditions on the formation of these compounds was studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1562–1570, October, 2007.  相似文献   

4.
Carbonylation of (E)-2-(4-halobenzylidene)-p-menthan-3-ones, catalyzed by PdCl2(PPh3)2, gave a distereometric mixure of 4-[(1R,4R)- and (1R,4S)-3-oxo-p-menthan-2-ylidenemethyl]benzoic acids, whose reaction with phenols gave 1R,4R diastereomers of the corresponding esters.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 659–664.Original Russian Text Copyright © 2005 by Drushlyak, Kutulya, Pivnenko, Vashchenko.  相似文献   

5.
2-Polyfluoroalkylchromene-4(4H)-thiones, synthesized from 2-polyfluoroalkylchromones and P2S5, react with aniline, phenylhydrazines, and hydroxylamine at the C(4) atom and afford corresponding anils, phenylhydrazones, and oximes of chromones. On heating in alcohol in the presence of concentrated HCl, chromone phenylhydrazones and oximes undergo ring closure to form 3-(2-hydroxyaryl)-1-phenyl-5-polyfluoroalkylpyrazoles and 5-hydroxy-3-(2-hydroxyaryl)-5-polyfluoroalkyl-Δ2-isoxazolines.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2188–2195, October, 2004.  相似文献   

6.
Oxidation of amalgamated magnesium metal with 3,6-di-tert-butyl-o-benzoquinone (1) in different aprotic organic solvents afforded magnesium catecholate and bis-o-semiquinolate complexes. The catecholate derivatives of magnesium CatMgL2 (Cat is the 3,6-di-tert-butyl-o-benzoquinone dianion, L = THF or Py) were synthesized in high yields in pyridine and tetrahydrofuran, respectively. The reactions in diethyl ether or dimethoxyethane produced hexacoordinated metal bis-o-semiquinolates SQ2MgLn (SQ is the 3,6-di-tert-butyl-o-benzoquinone radical anion, L = Et2O, n = 2; L = DME, n = 1). The reaction with the use of toluene as the solvent gave a magnesium bis-o-semiquinolate complex containing the coordinated unreduced o-quinone molecule. The molecular structures of the [CatMgPy2]2 and SQ2Mg·DME complexes were established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 92–98, January, 2007.  相似文献   

7.
Summary. The three-component condensation of aldehyde, N,N′-dimethylbarbituric acid and alkyl or aryl isocyanide afforded the corresponding furo[2,3-d]pyrimidine-2,4(1H,3H)-diones in 1-butyl-3-methylimidazolium bromide as an ionic liquid in high yields at room temperature within several minutes.  相似文献   

8.
Reaction of 2,2-dimethyltetrahydro-2H-pyran-4-one with aqueous methanamine, followed by reduction of the Schiff base thus obtained with sodium tetrahydridoborate gave N,2,2-trimethyltetrahydro-2H-pyran-4-amine which was subjected to cyanoethylation with acrylonitrile. The resulting 3-(2,2-dimethyltetrahydro-2H-pyran-4-ylmethylamino)propanenitrile was reduced with lithium tetrahydridoaluminate to N-(2,2-dimethyltetrahydro-2H-pyran-4-yl)-N-methylpropane-1,3-diamine, and some chemical transformations of the latter were studied.  相似文献   

9.
New sterically hindered functionalized o-quinones were synthesized by the 1,4-nucleophilic addition of secondary cyclic amines to 3,6-di(tert-butyl)-o-benzoquinone. The ability of these o-quinones to form o-semiquinone complexes with transition and main-group metals was studied by ESR spectroscopy in solution. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1786–1793, September, 2007.  相似文献   

10.
In the study of reactions of N-alkyl- and N-aryltrihalogenoacetamides with PCl5, it was demonstrated for the first time that 3-alkyl(aryl)-2,2,2,4 tetrachloro-4-trihalomethyl-1,3,2-λ5-oxazaphosphetanes are intermediates in the synthesis of trihaloacetimidoyl chlorides. According to quantum-chemical calculations, acyclic N-tetrachlorophosphoranes, which are the primary products in the reactions of trihaloacetamides with PCl5, undergo rapid cyclization into the corresponding phosphorates and subsequent 1,3-chlorotropic migration gives rise to oxazaphosphetanes with the five-coordinate P atom.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 739-744, March, 2005.  相似文献   

11.
N-Bromo and N-chlorosuccinimides add to 1-phenyltricyclo[4.1.0.02,7]heptane in CH2Cl2 with cleavage of the C(1)-C(7) bond to give isomeric 1 : 1 Markownikoff-type endo, anti-adducts of the norpinane structure in a ∼3 :7 ratio corresponding to N and O alkylation of succinimide.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No.2, pp. 457–460, February, 2005  相似文献   

12.
ESR spectroscopy was used to study a series of mono- and binuclear o-semiquinone metal complexes, viz., derivatives of sterically hindered di-o-quinone 1,2-bis(2,5-di-tert-butylcyclohexadiene-1,5-dion-3,4-yl)ethane (1). Hindered rotation was found in the o-semiquinone moiety of the generated complexes. Magnetochemical measurements for polymeric bis(o-semiquinolate)copper(II) based on di-o-quinone 1 showed two antiferromagnetic channels of interaction between the paramagnetic centers. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1580–1584, July, 2005.  相似文献   

13.
A new compound (5R, 10R)-3,8-dihydroxy-5,10-diethoxy-5,10-dihydrochromeno[5,4,3-cde]chromene monohydrate was obtained from 3,4-dihydroxybenzaldehyde in aerobic basic aqueous ethanol solution in the presence of manganese chloride and triethylamine and crystallized in orthorhombic P212121 space group (denoted as 1). When 1 was recrystallized from aqueous methanol, it was transformed to another crystal (2) with the same composition but in P21/n space group. The drastic difference in the extensive hydrogen bond network makes 1 a 3D and 2 a 2D infinite supramolecular structure, respectively.  相似文献   

14.
3-Substituted 1H,5H-naphtho[1,8-ef][1,3]dithiocines (R = H, Me, Ph, t-Bu) were oxidized with m-chloroperoxybenzoic acid to the corresponding 2-oxides having trans configuration (R ≠ H). According to the 1H and 13C NMR data (including NOESY experiments), the disubstituted compounds at room temperature exist in a boat conformation with equatorial orientation of the substituent on C3 and oxygen atom on S2. The compound with no substituent on C3 gives rise to a mixture of boat conformers with axial and equatorial sulfoxide oxygen atoms at a ratio of 83:17.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1109–1112.Original Russian Text Copyright © 2005 by Kikilo, Khairutdinov, Shtyrlin, Klochkov, Klimovitskii.  相似文献   

15.
3,3,3-Trifluoro-N′-(3-trifluoromethylphenyl)-1,2-propanediamine (5) was synthesized by the reaction of 2-diazo-1,1,1-trifluoro-3-nitropropane or 3,3,3-trifluoro-1-nitropropene with 3-aminobenzotrifluoride followed by the reduction of the nitro group. The Michael 1,4-addition of diamine 5 to acrylic acid occurs only at the N(1) atom and affords N-mono-or N,N-dicarboxyethyl derivatives 6 and 7, depending on the reactant ratio. Protolytic equilibria 5–7 in aqueous solutions were studied by pH-potentiometry and UV spectroscopy. Only the aliphatic amino group can be protonated in an aqueous solution, while the aromatic amino group remains unprotonated even in 12 M HCl. The stability constants of transition metal (Cu2+, Ni2+, Zn2+) complexes with ligands 5–7 were determined by pH-potentiometric titration. The stability of the complexes and selectivity of the ligands toward Cu2+ ions increase with an increase in the number of N-carboxyethyl groups. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2465–2469, November, 2005.  相似文献   

16.
Addition of ethyl-, propyl-, and n-butylmercaptans to 1-O-allyl-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose in the presence of benzoyl peroxide catalyst was studied for the first time. The products were 1-O-(3-ethylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose, 1-O-(3-propylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose, and 1-O-(3-butylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose. Deacetylation of 1-O-(3-ethylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose produced 1-O-(3-ethylthiopropyl)-β-D-galactopyranose. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 209–211, May–June, 2007.  相似文献   

17.
A method is developed for the preparation of 4-(vic-triazol-1-yl)indoles that involves replacement of the ortho-NO2 group in E-2,4,6-trinitrostilbenes by an azido group, condensation of E-2-azido-4,6-dinitrostilbenes with acetylacetone, replacement of the second ortho-NO2 group in the resulting stilbenes by N3, and subsequent thermolysis of the azide into the target indole. The reactions of E-2-azido-4,6-dinitrostilbenes with cyclohexane-1,3-dione gave E-2-amino-4,6-dinitrostilbenes, which can be used for selective transformation of the ortho-NO2 group into an amino group in E-2,4,6-trinitrostilbenes. 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. 1293–1296, May, 2005.  相似文献   

18.
Summary The properties of the inner and the external aqueous phases, were studied in w/o/w multiple emulsions with light microscopic image analysis and differential scanning calorimetry (DSC). The importance of multiple emulsions lies in the presence of these aqueous phases, making them available for sustained, controlled drug delivery systems. Differentiation of these two aqueous phases, studying the effect of manufacturing technology on droplet structure, quantitative determination of phase volumes and any changes occurring during storage are essential when planning w/o/w emulsions. The present study uses microscopic observations combined with DSC measurements in order to identify the formed structure, at developmental stage in case of different components, preparation methods, and stirring rates. These tools are beneficial during manufacturing as in process controls, or to ensure product quality.  相似文献   

19.
An ab initio (6-31G**) study of binary associates of aniline and n-propylamine with nitrobenzene and m-cresol has been carried out. The structures corresponding to the total energy minimum of the system have been found for the associates, and their geometrical and energy characteristics have been determined. Basic types of intermolecular interactions have been established, and their effects on the reactivity of the amino group have been investigated.Original Russian Text Copyright © 2004 by I. A. Novakov, V. V. Korolkov, A. I. Pavlyuchko, B. S. Orlinson, and L. A. GribovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 595–601, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

20.
Several α,ω-bifunctional derivatives of E,E,E-geranylgeraniol were prepared via convergent synthesis starting with geraniol (8), which was converted in three steps into the tetrahydropyranyl ether of 8-chlorogeraniol (9) and 8-hydroxygeranylphenylsulfone (10). Combination of synthons 9 and 10 with subsequent reductive removal of the phenylsulfonyl group produced the tetrahydropyranyl ether of ω-hydroxygeranylgeraniol (5), hydrolysis of which gave exclusively trans-ω-hydroxygeranylgeraniol (1). Derivatives 5–7 of geranylgeraniol were synthesized using standard methods. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 231–234, May–June, 2007.  相似文献   

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