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21.
B. A. Trofimov A. G. Mal’kina O. A. Shemyakina R. N. Kudyakova L. V. Sokolyanskaya L. M. Sinegovskaya A. I. Albanov V. I. Smirnov O. N. Kazheva A. N. Chekhlov O. A. D’yachenko 《Russian Journal of Organic Chemistry》2005,41(6):884-890
4-Hydroxy-4-methyl-2-pentynonitrile reacts with aniline, N-methylaniline, and 2-naphthylamine under mild conditions (20–80°C) to afford the corresponding 4-arylamino-2-(2-imino-5,5-dimethyl-2,5-dihydro-4-furylimino)-5,5-dimethyl-2,5-dihydrofurans in one preparative step. According to the X-ray diffraction data, both imino groups in the products have syn configuration with respect to the ring oxygen atom.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 903–909.Original Russian Text Copyright © 2005 by Trofimov, Mal’kina, Shemyakina, Kudyakova, Sokolyanskaya, Sinegovskaya, Albanov, Smirnov, Kazheva, Chekhlov, D’yachenko. 相似文献
22.
T. E. Glotova M. Yu. Dvorko N. N. Chipanina A. I. Albanov L. V. Sherstyannikova O. N. Kazheva A. N. Chekhlov O. A. D’yachenko 《Russian Journal of Organic Chemistry》2008,44(1):114-119
Thiocarbonohydrazones derived from aromatic aldehydes reacted with 4-phenylbut-3-yn-2-one in aqueous acetic acid (20°C, 2 h) to produce previously unknown N″-[(E-s-cis)-arylmethylidene]-N″′-[(Z-s-trans)-1-methyl-3-phenylprop-2-yn-1-ylidene]thiocarbonohydrazides with high chemo-, regio-, and stereoselectivity. The steric structure of N″-[(E-s-cis)-benzylidene]-N″′-[(Z-s-trans)-1-methyl-3-phenylprop-2-yn-1-ylidene]thiocarbonohydrazide in crystal and in solution was studied by X-ray analysis and IR and NMR spectroscopy. 相似文献
23.
T. E. Glotova M. Yu. Dvorko A. I. Albanov O. N. Kazheva G. V. Shilov O. A. D’yachenko 《Russian Journal of Organic Chemistry》2008,44(10):1532-1537
3-Phenylamino-5-phenylimino-1,2,4-dithiazole reacted with 1-acyl-2-phenylacetylenes in ethanol or toluene on heating (78–80°C, 1 h) in chemo- and regioselective fashion to give previously unknown N-[5-acyl-3,4-diphenyl-1,3-thiazol-2(3H)-ylidene]-N′-phenylthioureas (yield 57–60%). The structure of N-[5-benzoyl-3,4-diphenyl-1,3-thiazol-2(3H)-ylidene]-N′-phenylthiourea was proved by X-ray analysis. 相似文献
24.
Nina K. Gusarova Svetlana F. Malysheva Olga N. Kazheva Oleg A. Dyachenko 《Tetrahedron letters》2010,51(14):1840-6987
Secondary phosphines, elemental selenium, and the natural alkaloids, lupinine and anabasine, interact in a three-component-type reaction under mild conditions (70 °C, 1-1.5 h, EtOH) without the formation of any by-products to give diselenophosphinates of the above-mentioned alkaloids (in almost quantitative yields) with the retention of their intrinsic optical activity. Thus, the developed synthesis represents an atom-economic route to new selenophosphorus derivatives of alkaloids. 相似文献
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26.
N. A. Kondratova O. N. Kazheva G. G. Aleksandrov O. A. D’yachenko V. F. Traven 《Russian Chemical Bulletin》2009,58(9):1908-1914
2,3-Dihydrofuro[3,2- c]coumarin-3-one reacts with aromatic amines in two pathways, depending on the solvent. The reactions in ethanol afford its enamines, while the use of acetic acid favors the formation of enamines of the 2,3-dihydrofuro[3,2-c]coumarin-3-one dimer. Electronic absorption spectroscopy in different solvents revealed that the enamines obtained can undergo tautomeric transformations. The product of a reaction of 2,3-dihydrofuro-[3,2-c]coumarin-3-one with 4-bromoaniline exists in the enamine form (X-ray diffraction data). 相似文献
27.
O. G. Khudina Ya. V. Burgart E. V. Shchegol’kov V. I. Saloutin O. N. Kazheva A. N. Chekhlov O. A. D’yachenko 《Russian Journal of Organic Chemistry》2009,45(6):801-809
Steric structure of fluorinated 2-arylhydrazono-3-oxo esters was studied by 1H, 19F, and 13C NMR spectroscopy and X-ray analysis. It was found that these compounds in the crystalline state and in solutions in acetone-d 6, DMSO-d 6, and CDCl3 exist as Z isomers with the ester fragment involved in intramolecular hydrogen bond with the hydrazone NH proton. Exceptions are alkyl 2-arylhydrazono-4,4-difluoro-3-oxobutanoates which exist in acetone-d 6 as mixtures of Z and E isomers, the former prevailing. Unlike fluorinated analogs, ethyl 2-(4-methylphenyl)hydrazono-3-oxobutanoate in crystal has the structure of E isomer in which intramolecular hydrogen bond is formed between the NH proton and acetyl carbonyl group. The same compound in acetone-d 6, DMSO-d 6, and CDCl3 gives rise to a mixture of Z and E isomers, the latter prevailing. 相似文献
28.
V. F. Traven I. V. Ivanov V. S. Lebedev T. A. Chibisova B. G. Milevskii N. P. Solov’eva V. I. Polshakov G. G. Alexandrov O. N. Kazheva O. A. Dyachenko 《Russian Chemical Bulletin》2010,59(8):1605-1611
According to 1? and 13? NMR data, enamines of 3-formyl-4-hydroxycoumarin exist in the keto enamine tautomeric form and undergo Z/E-isomerization around the C=C bond in CDCl3, DMSO-d6, and CD3OD at room temperature. The activation energies of ?/Z-isomerization were measured experimentally and calculated by the B3LYP/6-311++G(d,p) method. An X-ray diffraction study showed that 3-(benzyliminomethyl)chromane-2,4-dione in the crystalline state exists as a mixture of two keto enamine isomers. 相似文献
29.
Olga N. Kazheva Grigorii G. Alexandrov Andrey V. Kravchenko Igor B. Sivaev Vladimir I. Bregadze 《Journal of organometallic chemistry》2006,691(20):4225-4233
New radical cation salts (TMTSF)2[3,3′-Co(1,2-C2B9H11)2] (1), (TTF)[3,3′-Co(1,2-C2B9H11)2] (2) and (ET)[3,3′-Co(1,2-C2B9H11)2] (3) were synthesized and their crystal structures and electrical conductivities were determined. Compound 1 has layered structure with conducting stacks of the TMTSF cations, whereas compounds 2 and 3 contain separated pairs of fulvalenium cations. Conductivity of crystals 1 at room temperature was found to be 15 Ohm−1 cm−1, that is the maximum value found for fulvalenium metallacarborane salts. 相似文献
30.
In this paper, we present some new properties of the Mitra‐Wan forestry model written as a discrete‐time optimal control problem. For this problem, the set of stationary states is characterized. For the optimal long‐run management, we consider the following optimality criteria: average optimality, good control policies, bias optimality, and overtaking optimality. We establish relationships between these criteria and show that the value of average optimal policies is constant and equals the value in the optimal stationary state. 相似文献