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11.
G. V. Grishina S. A. Abdulganeeva V. M. Potapov I. A. Ivanova A. A. Espenbetov Yu. T. Struchkov I. A. Grishina A. I. Lutsenko 《Chemistry of Heterocyclic Compounds》1985,21(12):1362-1368
The Michael addition of acrylonitrile to the pyrrolidine enamine of 1-(S--phenyl-ethyl)-4-piperidone proceeds with the formation of. a 1:1 mixture of l-(S--phenyl ethyl)-3-(2-cyanoethyl)-4-piperidone diastereomers. A diastereomer isolated in pure form was shown by x-ray diffraction structural analysis to have S-configuration of the new chiral center at C(3) of the piperidone ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp, 1656–1662, December, 1985. 相似文献
12.
, , , . .
Dedicated to Professors K. Tandori and L. Leindler on the occasion of their anniversaries
This work was completed in support of the Russian Foundation of Fundamental Research (Project # 96-01-00094) and of the International Scientific Foundation (Grant # NCI-300). 相似文献
Dedicated to Professors K. Tandori and L. Leindler on the occasion of their anniversaries
This work was completed in support of the Russian Foundation of Fundamental Research (Project # 96-01-00094) and of the International Scientific Foundation (Grant # NCI-300). 相似文献
13.
M. N. Kotov V. F. Masterov V. V. Potapov A. V. Prichodko O. V. Smertin N. M. Shybanova 《International Journal of Infrared and Millimeter Waves》1993,14(8):1679-1687
Experimental investigations of superconductivity effects in single-phase and multiphase Bi2Sr2CaCu2O8 single-crystals have been carried out at 142 GHz frequency by means of the standing wave profile method [1]. Josephson harmonic generation has been observed to be responsible for the appearence of additional peaks on the standing wave profile of the open dielectric resonator loaded with a properly orientated multiphase high-Tc superconductor specimen. This leads to the conclusion that most of the Josephson junctions in multiphase crystals are located in certain crystallographic planes. The investigations of temperature dependencies showed that sharp resonant peaks of conductivity observed earlier [2] at 60 GHz could also be observed at 142 GHz. 相似文献
14.
The review summarizes the results of studies in the field of development of efficient proceduresfor the synthesis of dialkyl chalcogenides, dialkyl dichalcogenides, vinyl and ethynyl chalcogenides, andselenium-, tellurium-, and silicon-containing heterocyclic compounds on the basis of elemental seleniumand tellurium. 相似文献
15.
A. Z. Yankelevich A. M. Sergeev S. V. Rykov V. K. Potapov G. A. Nikiforov 《Russian Chemical Bulletin》1986,35(12):2457-2461
Conclusions It has been established by kinetic and spectral methods that the cyclohexadiene carbene generated in the photolysis of 2,6-di-tert-butyl-1,4-benzoquinone diazide in benzene predominantly in the singlet state reacts with benzene to form a norcaradiene derivative, which isomerizes thermally to 4-phenylcyclohexadiene-2,5-one. The latter is converted thermally to 2,6-di-tert-butyl-4-phenylphenol.Translated from Izvestiya Akadeinii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2680–2685, December, 1986. 相似文献
16.
L. G. Kuz'mina Yu. T. Struchkov V. V. Dunina O. A. Zalevskaya V. M. Potapov 《Russian Chemical Bulletin》1986,35(8):1639-1645
Conclusions By x-ray crystallographic analysis of (+)-D-[(SC,RN)-N-methyl-N-isopropyl-o-methyl-benzylaminato-2C,N]-(acetylacetonato-O,O)palladium(II) it was established that with the S configuration of the asymmetric carbon center the adjacent nitrogen atom is fixed in the R configuration during coordination with the metal. Attractive interaction was detected between the H atom of one of the Me groups of theN-isopropyl substituent and the palladium atom. It was shown that it has a stabilizing effect on the ortho-palladized metal ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1807–1813, August, 1986. 相似文献
17.
R. R. Akhmerov M. I. Kamenskii A. S. Potapov A. E. Rodkina B. N. Sadovskii 《Journal of Mathematical Sciences》1984,24(6):674-719
In the paper we present a survey of the investigations on the theory of equations of neutral type, i.e., equations for which the value of the derivative at the present moment depends explicitly on the prehistory of the behavior of the derivative. The paper consists of eleven sections.Translated from Itogi Nauki i Tekhniki, Seriya Matematicheskii Analiz, Vol. 19, pp. 55–126, 1982. 相似文献
18.
M. G. Voronkov S. N. Adamovich V. A. Potapov V. I. Rakhlin B. Z. Shterenberg R. G. Mirskov S. V. Amosova 《Russian Chemical Bulletin》1987,36(8):1723-1724
Conclusions Transetherification of methylvinyldialkoxyslianes by diols (HOCH2CH2)2M (M=O, S, Se, and Te) gave 2-methyl-2-vinyl-1,3-dioxa-6-chalcogena-2-silacyclooctanes CH3 (CH2=CH)Si(OCH2· CH2)2M. The IR, NMR, and mass spectra of these compounds were studied.29Si NMR spectroscopy indicated that there is a transannular interaction in such heterocycles only in the case of M=Te.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1859–1861, August, 1987. 相似文献
19.
I. G. Il'ina N. B. Kazennova E. V. Yurasova V. M. Potapov 《Chemistry of Heterocyclic Compounds》1973,9(4):485-487
A number of difficult-to-obtain heterocyclic compounds — tetrahydroquinolino- and quinolinopyrazines — were synthesized from o-dinitrotetrahydroquinolines. The UV spectra of the synthesized compounds were studied.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 525–527, April, 1973. 相似文献
20.
Yu.A. Ustynyuk P.I. Zakharov A.A. Azizov V.K. Potapov I.M. Pribytkova 《Journal of organometallic chemistry》1975,88(1):37-64
Dissociative ionisation of organometallic cyclopentadiene derivatives containing one, two or three M(CH3)3 groups (M Si, Ge, Sn) has been studied.Among the monometallated compounds, C5H5Si(CH3)2Cl, C5H5Si(CH3)2OCH3 and (C5H5)4Sb have also been investigated. To verify fragmentation patterns, the spectra of deuterated compounds such as C5D5Si(CH3)3, C5D5Sn(CH3)3, C5D4Si2(CH3)6 and C5D3Si3)9 have been measured. Dissociative ionisation of h1-cyclopentadienyl derivatives has been shown to differ essentially from that of h5-compounds. 相似文献