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1.
Amelichev SA Aysin RR Konstantinova LS Obruchnikova NV Rakitin OA Rees CW 《Organic letters》2005,7(25):5725-5727
[chemical reaction: see text]. Treatment of N-substituted 2,5-dimethylpyrroles 2 with an equilibrated mixture of disulfur dichloride and DABCO in chloroform at 0 degrees C gives pentathiepinopyrroles 3 in moderate yields; further reaction of 3 with the same mixture at room temperature leads, in an extensive reaction cascade, to bis(dithiolo)pyrroles 4 in high yield; 2 can be converted into 4 in a one-pot operation under unusually mild conditions. 相似文献
2.
Lidia S. Konstantinova Natalia V. Obruchnikova Yulia V. Nelyubina Oleg A. Rakitin 《Tetrahedron》2010,66(24):4330-634
The treatment of 5H-1,2,3-dithiazole-5-thiones 1 in chloroform under reflux and 5H-1,2,3-dithiazol-5-ones 2 in THF at room temperature with primary aliphatic amines and benzylamine afforded 1,2,5-thiadiazole-3(2H)-thiones 3 and 1,2,5-thiadiazol-3(2H)-ones 6, respectively. The structure of dithiazolone 3f was confirmed by X-ray diffraction analysis. The reaction of dithiazolone 2e bearing an electron-donating methyl group in the 4-position gave 2-oxoacetamide 7e in high yield. The reaction of thiones 1 with secondary aliphatic amines in DMSO yielded 2-iminothioacetamides 8 in moderate yields together with elemental sulfur. Interestingly, the treatment of dithiazolones 2 with secondary amines under the same conditions afforded 2-oxoacetamides 9—the products of the hydrolysis of corresponding imino derivatives 10, which was isolated as 10b. A general mechanism was proposed for the formation of the products. 相似文献
3.
N. V. Obruchnikova R. A. Novikov S. G. Zlotin P. V. Dorovatovskii V. N. Khrustalev O. A. Rakitin 《Russian Chemical Bulletin》2018,67(11):2044-2048
The oxidation of hexane-2,3,4,5-tetraone tetraoxime with dinitrogen tetroxide was studied in different solvents. The primary furoxan ring closure was found to occur involving either two central or two terminal oxime groups to form 4,7-dimethyl[1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxide and the previously unknown 4,4′-dimethyl-[3,3′-bi(1,2,5-oxadiazole)] 5,5′-dioxide. The structure of the latter compound was established by X-ray diffraction. 相似文献
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V. A. Ogurtsov O. A. Rakitin Yu. A. Strelenko N. V. Obruchnikova L. I. Khmel'nitskii 《Russian Chemical Bulletin》1993,42(4):706-708
Interaction of aromatic nitrile oxides with bis-trimethylsilylthiodiimide results in 2-amino-4-aryl-1,2,3,5-oxathiadiazoles, the first representatives of a new class of heterocyclic compounds.For Part 2, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 742–743, April, 1993. 相似文献
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Nikita S. Gudim Ekaterina A. Knyazeva Ludmila V. Mikhalchenko Ivan S. Golovanov Vadim V. Popov Natalia V. Obruchnikova Oleg A. Rakitin 《Molecules (Basel, Switzerland)》2021,26(16)
This paper presents an improved synthesis of 4,7-dibromobenzo[d][1,2,3]thiadiazole from commercially available reagents. According to quantum-mechanical calculations, benzo[d][1,2,3]thiadiazole (isoBTD) has higher values of ELUMO and energy band gap (Eg), which indicates high electron conductivity, occurring due to the high stability of the molecule in the excited state. We studied the cross-coupling reactions of this dibromide and found that the highest yields of π-spacer–acceptor–π-spacer type compounds were obtained by means of the Stille reaction. Therefore, 6 new structures of this type have been synthesized. A detailed study of the optical and electrochemical properties of the obtained π-spacer–acceptor–π-spacer type compounds in comparison with isomeric structures based on benzo[c][1,2,5]thiadiazole (BTD) showed a red shift of absorption maxima with lower absorptive and luminescent capacity. However, the addition of the 2,2′-bithiophene fragment as a π-spacer resulted in an unexpected increase of the extinction coefficient in the UV/vis spectra along with a blue shift of both absorption maxima for the isoBTD-based compound as compared to the BTD-based compound. Thus, a thorough selection of components in the designing of appropriate compounds with benzo[d][1,2,3]thiadiazole as an internal acceptor can lead to promising photovoltaic materials. 相似文献
8.
Amelichev SA Konstantinova LS Obruchnikova NV Rakitin OA Rees CW 《Organic letters》2006,8(20):4529-4532
Fused aromatic and heterocyclic 1,2,3,4,5-pentathiepins react with triphenylphosphine and alkynes bearing electron-withdrawing groups to give the corresponding 1,4-dithiins in high yields. Unsymmetrical alkynes add regioselectively to afford products in agreement with the electron distribution in a proposed reaction intermediate. A mechanism for these reactions is proposed. 相似文献
9.
Lidia S. Konstantinova Ekaterina A. Knyazeva Natalia V. Obruchnikova Nadezhda V. Vasilieva Irina G. Irtegova Yulia V. Nelyubina Irina Yu. Bagryanskaya Leonid A. Shundrin Zhanna Yu. Sosnovskaya Andrey V. Zibarev Oleg A. Rakitin 《Tetrahedron》2014
A new general procedure for the selective synthesis of 1,2,5-thiadiazole 2-oxides (including fused derivatives) 8a,b,c,g,h from the reaction of vic-glyoximes with S2Cl2 and pyridine in acetonitrile was elaborated together with general procedure for the synthesis of 1,2,5-thiadiazoles 7a–i, 10, 12, and 14 from the same starting materials and reagents. Molecular structures of 3,4-dimethyl-1,2,5-thiadiazole 2-oxide 8a and [1,2,5]thiadiazolo[3,4-b]quinoxaline 10 were confirmed by single-crystal X-ray diffraction. Electrochemical properties of 1,2,5-thiadiazole 2-oxides 8 were studied by cyclic voltammetry and different behavior was observed for monocyclic and benzo-fused derivatives. With compounds 8g and 17, previously unknown deoxygenation of 2,1,3-benzothiadiazole 1-oxides was discovered by electrochemical reduction, and resulted 2,1,3-benzothiadiazoles 7g and 19 were detected in the forms of their radical anions by EPR spectroscopy combined with DFT calculations. 相似文献
10.
K. E. German M. S. Grigoriev C. Den Auwer A. Ya. Maruk Ya. A. Obruchnikova 《Russian Journal of Inorganic Chemistry》2013,58(6):691-694
The crystal structure was determined and the physicochemical properties were studied for tetrapropylammonium pertechnetate and perrhenate. Pr4NMO4 (M = Tc, Re) are isostructural and crystallize as colorless prismatic crystals in the orthorhombic system, space group Pna21, Z = 4. For M = Tc at 25°C, a = 13.22(4) Å, b = 12.35(3) Å, c = 10.13(4) Å; for M = Re at ?120°C, a = 13.169(2) Å, b = 12.311(2) Å, c = 10.107(1) Å. The Re-O distances are 1.677(12), 1.704(5), 1.719(4), and 1.739(11) Å. Each anion in this structure has four neighboring cations with Re…N distances of 5.06–5.34 Å. The solubility product of Pr4NTCO4 is (6.19 ± 0.50) × 10?5 mol2/L2. The Gibbs energy of dissolution of [(C3H7)4N]TcO4 in dilute aqueous solutions is 24.0 ± 0.5 kJ/mol. The association constant K 1 for (Pr4N+)…(TcO 4 ? ) in water and aqueous solutions is 10.8 ± 0.7 L/mol. The solubility of Pr4NTcO4 increases with the solution acidity, similarly to the solubility of Bu4NTcO4. Upon precipitation of Pr4NTcO4 from model solutions containing (2.0–7.5) × 10?2 mol/L Tc in 3–4 M HNO3, (2.0–7.5) × 10?8 mol/L 239PuO2(NO3)2, and 5.7 mCi/L 106Ru(NO)(NO3)3, the technetium decontamination factors from 239Pu and 106Ru were (0.5–1.5) × 102 and (6.0–7.5) × 102, respectively. 相似文献