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1.
We have synthesized complex compounds of Co(2+) chloride with hydrochlorides of N-(1,2,4-triazol-5-yl)benzamidine and N-(tetrazol-5-yl)benzamidine. According to magnetochemistry and electron spectroscopy data, the ligands are coordinated in a bidentate fashion with the N atom of the amidine group and the N atom of the heterocycle with formation of the tetrahedral chromophore CoN2Cl2.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2311–2315, October, 1992.  相似文献   

2.
Data on the application of the allylic derivatives of boron for the synthesis of piperidine, indolizine, pyrrolizidine, and indole alkaloids are reviewed.A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow. N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1015–1027, August, 1999.  相似文献   

3.
The basic characteristics of fluorosulfation of fluoroalkylhalides (effect of the structure of the polyfluoroalkyl, nature of the halogen, acid catalysis, etc.) with halogen fluorosulfates and peroxydisulfuryl difluoride were investigated. A mechanism was proposed for formation of fluorosulfonic acid fluoroalkyl esters based on the experimental and quantum chemical data.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1718–1732, August, 1992.  相似文献   

4.
Institute of Petrochemical Processes, Azerbaidzhan Academy of Sciences, 370025 Baku; N. N. Semenova Institute of Chemical Physics, Russian Academy of Sciences, 117334 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1230–1231, May, 1992.  相似文献   

5.
The factors determining the regioselectivily of nucleophilic addition to pyridinium and quinolinium cations are examined. Published data of the last IS years are summarized.N. D. Zelinski Institute of Organic Chemistry, Russian Academy of Sciences, Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 774–815, June, 1995. Original article submitted April 25, 1995.  相似文献   

6.
A method was developed for the production of derivatives of 4-trifluoromethyl-7-hydroxycoumarin with electron-withdrawing groups (CN, CF3CO) at position 3. The structure of 3-cyano-4-trifluoromethyl-7-acetoxycoumarin was proved by x-ray crystallographic investigation. The effect of the substituents on the geometry of the molecule is discussed.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, 117813 Moscow. Institute of Biochemistry, Academy of Sciences of Armenia, 375044 Erevan. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1371–1375, June, 1992.  相似文献   

7.
Some differences were observed in the solid- and liquid-phase benzylic oxidation of 2-(hydroxy- or dialkylamino)-methyl-4,6-di-tert-butylphenols. Oxidation of these semi-hindered phenols with lead tetraacetate gave a new compound: 3,5-di-tert-butyl-ortho-benzoquinone diacylal.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Institute of Synthetic Polymeric Materials, Russian Academy of Sciences, 117393 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2380–2384, October, 1992.  相似文献   

8.
4-Methyl-5-(2,2,2-trichloroethyl) derivatives of 2-thiazolethione and 2-amino-3-hydroxythiazolium chloride were synthesized from 3-thiocyanato-5,5,5-trichloro-2-pentanone. The structures of these derivatives were determined using spectral data and x-ray diffraction structural analysis.For Communication 7, see [1]N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117813. A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences Moscow 117813. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 832–838, June, 1998.  相似文献   

9.
The effect of the position and nature of substituents on the recyclization of substituted furoxans has been established.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences (RAN), Moscow 117913, Russia Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences (RAN), Chernogolovka 142432, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 202–209, February, 1999.  相似文献   

10.
A study has been made of the electrochemical fluorosulfation of perfluoro-2-alkenes in the presence of halogens, leading to the formation of fluoroaliphatic vicinal fluorosulfatohalides. The reaction proceeds as a conjugate radical addition of peroxydisulfuryl difluoride and the halogen at the double bond of the olefin; the ratio of the resulting regioisomers is determined by steric factors.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, Moscow 117813. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 1005–1011, April, 1992.  相似文献   

11.
Based on CNDO/2 (spd basis) quantum chemical calculations of the proton affinity, we propose a model describing the nature of the interaction between the proton and the molecule of phosphoryl compounds in the monocation X3POH+. We have established that in the series of phosphoryl compounds, the change in the proton affinity is subject to two effects: the shift in electron density from the base to the proton, and the ionic interaction between the proton complexing agent and the phosphorus atom and substituents; and in the latter case we observe electrostatic repulsion for the substituents R, OR, NR2 and attraction for F.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2579–2583, November, 1992.  相似文献   

12.
Phenomena associated with stereochemical nonrigidity of five-coordinate phosphorus fluorides (Berry pseudorotation and restricted rotation of different functional groups about the bond with the central phosphorus atom) have been analyzed. The main cause of restricted rotation isp d bonding of unsharedp-electron pairs of substituents with vacantd-orbitals of the phosphorus. Additional stabilization of the molecule occurs when it is possible to form an H...F hydrogen bond between the liquid and an axial fluorine atom in the phosphorane. The relationship between pseudorotation and restricted rotation is considered.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1784–1793, August, 1992.  相似文献   

13.
The15N NMR chemical shifts for the analogous diamagnetic adduct of 3,5-dipropyl-4-ethylpyrazole with cadmium dibromide were measured to obtain reference data for estimating the isotropic paramagnetic NMR shifts of nitrogen in paramagnetic adducts of alkylpyrazoles with transition metal salts. The13C and1H NMR spectra were obtained for the same adduct in conditions of frozen protometallotropic rearrangement of the hydrogen in the NH group and the temperature-dependent NMR spectra of isotopes of Cd were made.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, Moscow 117813. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 756–761, June, 1998.  相似文献   

14.
New heterogeneous catalysts based on the complexes of platinum with tin(II) citrate were prepared. The catalysts exhibit high selectivity in the hydrogenation of allylbenzene to propylbenzene without increasing the rate of isomerization of the C=C bond. The activity of the complexes depends on the conditions and decreases with increase in the Sn:Pt ratio.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. St. Petersburg Technological Institute. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1287–1290, June, 1992.  相似文献   

15.
The kinetic acidity of 2,6-di-tert-butyl-4-hydroxyphenoxyl in tetrahydrofuran has been estimated by means of ESR. It is shown that ion pairs are formed in the process of proton transfer from the radical to triethylamine.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2512–2516, November, 1992.  相似文献   

16.
The oxidation of substituted aminonitrotriazole oxides to the corresponding dinitro derivatives of triazole and azotriazole oxides has been studied. Communication 1, see ref. [1]. N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow, Russia; e-mail: cheminst@mail.psu.ru. Institute of Chemical Physics at Chernogolovka, Russian Academy of Sciences, 124432 Chernogolovka, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1356–1362, October, 1999.  相似文献   

17.
The structure of 1-methylmorpholinium 6-methyl-4-phenyl-3-cyano-5-ethoxycarbonyl-1,4-dihydro-2-pyridineselenolate was studied using x-ray diffraction analysis. It was found that the 1,4-dihydropyridine ring has a boat conformation, and the plane of the pseudoaxial phenyl substituent is perpendicular to the bottom of this boat. In the anion, the C–Se bond length, which is 1.882(2) Å, indicates that the negative charge is formally located on the Se atom. The anions and cations of the salt in the crystal are linked by intermolecular hydrogen bonds.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, Moscow 117813, Russia. T. G. Shevchenko Lugansk State Pedagogical Institute, Lugansk 348011, Ukraine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 785–789, June, 1998.  相似文献   

18.
The kinetics of nitrosation of ascorbic acid by nitrite in unbuffered aqueous solutions was measured in the pH range from 6.7 to 4.0 at 25°C. The reaction order with respect to the proton is reliably lower than 2, especially in a more acidic solution. This means that under the studied conditions unprotonated nitrous acid may be involved directly in nitrosation of ascorbic acid.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1540–1544, July, 1992.  相似文献   

19.
Deformations of Na, Ca, and Ba vermiculites upon sorption of water vapor have been determined by a dilatometric method. Sequential stages in the hydration of interlayer exchange cations have been identified. The experimental results have been compared with data obtained in studies using adsorptive, calorimetric, and x-ray methods.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Institute of Colloid Chemistry and the Chemistry of Water, Academy of Sciences of the Ukraine, Kiev. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 34–39, January, 1992.  相似文献   

20.
A study was carried out on electrophilic addition and hydrolytic dissociation of 2,4,6-tris[di(tert-butoxycarbonyl)methylene]hexahydro-1,3,5-triazine. Chloro, bromo, and methyl derivatives of tris[di(tert-butoxycarbonyl)methyl]-1,3,5-triazine were synthesized for the first time as well as 2,4,6-tris-(tert-butoxycarbonylmethyl)-1,3,5-triazine. For Communication 1, see ref. [1]. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow and Institute of Chemical Physics, Russian Academy of Sciences at Chernogolovka, 142432 Chernogolovka, Moscow Oblast. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1404–1407, October, 1998.  相似文献   

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