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排序方式: 共有163条查询结果,搜索用时 15 毫秒
1.
V. F. Mironov A. V. Bogdanov A. V. Nemtarev A. A. Shtyrlina E. N. Varaksina V. K. Cherkasov A. B. Dobrynin D. B. Krivolapov R. Z. Musin I. A. Litvinov A. I. Konovalov 《Russian Chemical Bulletin》2007,56(9):1900-1910
The reactions of 3,5-di(tert-butyl)-1,2-benzoquinone with aryl-and alkylacetylenes in the presence of phosphorus trichloride afford 4-aryl(alkyl)-8-tert-butyl-2,6-dichloro-2-oxo-2H-benzo[e][1,2]oxaphosphinines as the major ipso-substitution products of the tert-butyl group by the chlorine atom. 4-Aryl(alkyl)-6,8-di(tert-butyl)-2,5-dichloro-2-oxo-and 4-aryl(alkyl)-6-tert-butyl-2,8-dichloro-2-oxo-2H-benzo[e][1,2]oxaphosphinines were obtained as the minor products. The structures of the stable representatives of this series were
confirmed by X-ray diffraction.
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1836–1845, September, 2007. 相似文献
2.
Yu. Yu. Kotorova A. T. Gubaidullin V. F. Mironov L. M. Burnaeva A. B. Dobrynin R. Z. Musin I. A. Litvinov I. V. Konovalova 《Russian Journal of General Chemistry》2006,76(3):437-446
The reaction of hexafluoroacetone with 2-alkoxy-6(7)-chloro-1,3,2-benzodioxaphosphorin-4-ones yielded 7-and 8-chloro-substituted 2-alkoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-1,3,2λ5-benzodioxaphosphepines. Their steric structure was studied by single-crystal X-ray diffraction. The effect of fluorinated substituents on the crystal packing of the benzophosphepines was demonstrated. Hydrolysis of these compounds gave the corresponding 4-and 5-chloro-substituted 2-(2-hydroxyphenyl)-2-oxo-1,1-bis(trifluoromethyl)-ethanols; the structure of 2-(2-hydroxy-5-chlorophenyl)-2-oxo-1,1-bis(trifluoromethyl)ethanol was also proved by single-crystal X-ray diffraction. 相似文献
3.
Michael A. Pudovik Lyudmila Kibardina Alexey Trifonov Alexey Dobrynin Sergei Katsyuba Alexander Burilov 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):120-126
New O-phosphorylated pyridoxal derivatives have been synthesized through the reaction of azomethines with РV acid chlorides. 2-Chloro-2-thioxo-5,5-dimethyl-1,3,2-dioxaphosphinanes and diethylchlorothiophosphate have been employed as phosphorylating agents. Regardless of the nature of the phosphorylating agent, the reaction is regioselective at phenolic hydroxyl group. The structure of final products is determined by the nature of the substituent at the nitrogen atom. If R is alkyl or cycloalkyl group, the products of the reaction represent phosphorylated pyridoxal imines, whereas phosphorylated furopyridines are formed in the case R is aryl substituent. 相似文献
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7.
A. V. Bogdanov V. F. Mironov A. B. Dobrynin O. I. Gnezdilov 《Russian Journal of Organic Chemistry》2013,49(11):1623-1627
Regioselective bromination of 4-phenyl-2,7-dichloro-2H-chryseno[6,5-e][1,2]phosphinine 2-oxide proceeded in the position 3 with the formation of 3-bromo-4-phenyl-2,7-dichloro-2H-chryseno[6,5-e][1,2] phosphinine 2-oxide; the structure of its 2-tert-butylamino derivative was established by XRD analysis and correlation spectroscopy. 相似文献
8.
Electrostatic assembly of multilayered thin films through sequential adsorption of polyions in layer-by-layer fashion utilizes the strong electrostatic attraction between oppositely charged molecules. We perform molecular dynamics simulations of multilayers of flexible polyelectrolytes around a charged spherical particle. Our simulations establish that the charge reversal after each deposition step is a crucial factor for the steady layer growth. The multilayers appear to be nonequilibrium structures. 相似文献
9.
N. A. Dobrynin 《Journal of Mathematical Sciences》2000,102(6):4566-4580
We consider dimensions of various homogeneous components in free partially commutative Lie (p-)superalgebras and offer a computational
algorithm for finding them.
Translated from Itogi Nauki i Tekhniki, Seriya Sovremennaya Matematika i Ee Prilozheniya. Tematicheskie Obzory. Vol. 74, Algebra-15,
2000. 相似文献
10.
Mironov V. F. Borisova Yu. Yu. Burnaeva L. M. Gubaidullin A. T. Dobrynin A. B. Litvinov I. A. Musin R. Z. Konovalova I. V. 《Russian Chemical Bulletin》2010,59(4):820-827
Phosphorylation of 2-hydroxyphenyl 2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl ketone with dichloro(phenyl)phosphine
gave 5-oxo-2-phenyl-4,4-bis(trifluoromethyl)-4,5-di-hydro-1,3,2-benzodioxaphosphepine. Heating of the latter initiated an
intramolecular interaction of the P atom with the carbonyl group. Hydrolysis of the intermediate product yielded 3-hydroxy-2-oxo-2-phenyl-3-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]-2,3-di-hydro-1,2λ5-benzo[d]oxaphosphole. The reaction was highly stereoselective (PRCS/PSCR). The reaction of the starting phosphepine with chloral proceeded highly stereoselectively (PRCSCS/PSCRCR) to give a 5-carbaphosphatrane derivative containing a four-membered ring, namely, 1-phenyl-3-trichloromethyl-10,10-bis(trifluoromethyl)-6,7-benzo-2,4,8,9-tetraoxa-1λ5-phosphatricyclo[3.3.2.01,5]decene. The trigonal bipyramid of the 5-carbaphosphatrane derivative is made up of the equatorial O atoms and the apical
C atoms. 相似文献