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1.
2.
A. V. Makarycheva-Mikhailova S. I. Selivanov N. A. Bokach V. Yu. Kukushkin P. F. Kelly A. J. L Pombeiro 《Russian Chemical Bulletin》2004,53(8):1681-1685
Reactions of the platinum(IV) nitrile complexes [PtCl4(RCN)2] (R = Me, CH2Ph, Ph) with 1,2- and 1,4-PhS(=NH)C6H4SPh in CH2Cl2 afforded addition products of sulfimides and coordinated nitriles, viz., the [PtCl4{NH=C(R)N=S(Ph)(C6H4SPh)}2] complexes. The latter were isolated in 75—90% yields and characterized by elemental analysis, positive-ion FAB mass spectrometry, IR spectroscopy, and 1H and 13C1H NMR spectroscopy. The temperature dependence of the 1H NMR spectra of the model [PtCl4{NH=C(R)N=SPh2}2] complexes (R = Me, Et) in CD2Cl2 studied in a temperature range from +40 to -70 °C demonstrated that E—Z isomerization of the ligands is a dynamic process in a range from +40 to -10 °C. The activation free energy of this process was calculated.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1618–1622, August, 2004. 相似文献
3.
I. A. Gluzdikov M. S. Egorov S. I. Selivanov G. L. Starova A. G. Shavva 《Russian Journal of Organic Chemistry》2006,42(11):1675-1682
Stereoselectivity of reaction with Raney nickel of D-homoestra-1,3,5(10),8,14-pentaenes containing one or two methyl groups in position 16 was investigated. The reaction direction is governed by the orientation of the substituent at C17a. The signals in the 1H and 13C NMR spectra of four synthesized compounds were completely assigned. Criteria for evaluation of the character of rings junction in analogs of D-homoequilenine were suggested. 16,16-Dimethyl-3-methoxy-D-homo-13α-estra-1,3,5(10),6,8-pentaen-17a-one was subjected to X-ray diffraction analysis. 相似文献
4.
K. Laihia A. Valkonen E. Kolehmainen R. Suontamo M. Nissinen V. Nikiforov S. Selivanov 《Journal of Molecular Structure》2005,754(1-3):77-84
The 1H and 13C NMR chemical shifts for six toxaphene congeners: 2-exo,3-endo,6-exo,8,9,10-hexachloro- (1), 2-exo,3-endo,5-exo,9,9,10,10-heptachloro- (2), 2-exo,3-endo,6-exo,8,9,10,10-heptachloro- (3), 2-exo,3-endo,5-exo,6-endo,8,9,10-heptachloro- (4), 2-exo,3-endo,5-exo,6-endo,8,9,9,10-octachlorobornane (5) and 2,5-endo,6-exo,8,9,9,10,10-octachloro-2-bornene (6) are reported. Their chemical shift assignments have been obtained by means of Pulsed Field Gradient (PFG) Double Quantum Filtered (DQF) 1H,1H correlation spectroscopy (COSY), PFG 1H,13C Heteronuclear Multiple Quantum Coherence (HMQC) and PFG 1H,13C Heteronuclear Multiple Bond Correlation (HMBC) experiments. A single crystal X-ray structural analysis was made for compounds 1, 3, 4 and 6. The prevalences of two octachlorobornene rotamers (6a,6b) were elucidated by ab initio MO method and single point DFT/GIAO calculations for 13C chemical shifts. Theoretical calculations proved that the single crystal structure of 6 corresponds its most stable conformer in solution. 相似文献
5.
V. V. Razin M. E. Yakovlev K. V. Shataev S. I. Selivanov 《Russian Journal of Organic Chemistry》2004,40(7):1027-1032
A three-step procedure has been developed for the synthesis of 3,5-disubstituted methyl pyridazine-4-carboxylates from accessible 2,3-disubstituted 2-cyclopropenecarboxylates. In the first step, cyclopropene derivatives react with diazomethane to give adducts having 2,3-diazabicyclo[3.1.1]hex-2-ene structure. The regio- and stereoselectivity of the cycloaddition has been determined. The second step is isomerization of the bicyclic adducts into 1,4-dihydropyridazine derivatives by the action of sodium methoxide. Finally, oxidation with potassium permanganate yields the target pyridazine-4-carboxylates. 相似文献
6.
V. I. Saloutin M. I. Kodess A. N. Fomin S. I. Selivanov B. A. Ershov K. I. Pashkevich 《Russian Chemical Bulletin》1988,37(2):318-321
Conclusions By1H and19F NMR spectroscopy it was shown that reaction of fluoroalkyl -ketoesters with methylhydrazine in deuteromethanol at –30 to 30C involves intermediate formation of the -ketoester salts with methylhydrazine and 3,5-dioxypyrazolidines which successively split off methanol and H2O with formation of 3-oxypyrazolines and pyrazol-5-ones, respectively.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 399–402, February, 1988. 相似文献
7.
O. A. Ignatenko M. A. Kuznetsov S. I. Selivanov 《Russian Journal of Organic Chemistry》2007,43(7):1042-1047
Oxidation of N-aminophthalimide with lead tetraacetate in the presence of 2-[(E)-2-arylethenyl]-5-phenyl-1,3,4-oxadiazoles gives the corresponding 2-(3-aryl-1-phthalimidoaziridin-2-yl)-5-phenyl-1,3,4-oxadiazoles. From 2-phenyl-5-[(1E,3E)-4-phenylbuta-1,3-dien-1-yl]-1,3,4-oxadiazole only the addition product at both C=C bonds was obtained, while in the reaction with 2,5-bis[(E)-2-phenylethenyl]-1,3,4-oxadiazole both mono- and bis-adducts were isolated. 相似文献
8.
N. I. Selivanov L. G. Samsonova T. A. Solodova T. N. Kopylova E. N. Tel’minov 《Optics and Spectroscopy》2013,114(3):373-378
The spectral and luminescent properties of acridine in SiO2 films synthesized by the sol-gel method using acid hydrolysis of tetraethoxysilane are studied. It is shown that acridine in films exists in protonated form. Ammonia-gas-sensing properties of films doped with acridine are studied by the fluorescence response (decrease in the intensity) of the protonated form. The possibility of multiple use of a sample without a noticeable decrease in its sensitivity is demonstrated. It is shown that the fluorescence response to a maximal permissible concentration of ammonia in the gas mixture with argon is 6–8%. 相似文献
9.
A reaction of aliphatic 1,2-hydroxylamino oximes bearing the hydroxylamino group at the secondary carbon atom with aromatic and heteroaromatic aldehydes in acetic acid leads to the corresponding 1-hydroxy-2-aryl(hetaryl)-4,5-dialkylimidazoles in high yields. α-Aryl(hetaryl)-nitrones initially formed by the condensation of 1,2-hydroxylamino oximes with aldehydes are quantitatively converted to the corresponding imidazoles. 相似文献
10.
S. N. Morozkina A. F. Fidarov S. I. Selivanov A. G. Shavva 《Russian Journal of Organic Chemistry》2014,50(10):1520-1526
New 8α-analogs of steroidal estrogens containing a fluorine atom in the 2-position have been synthesized with the goal of obtaining modified derivatives with improved biological characteristics. Some of the synthesized compounds have been found to display improved ratio of the osteoprotective and uterotropic effects. 2-Fluoro-16,16-dimethyl-d-homo-8α-estrone and its methyl ether exhibit hypocholesterolemic and cardioprotective activity and no uterotropic effect. 相似文献