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A. V. Prosyanik A. I. Mishchenko O. V. Zelenskaya A. Forni I. Moretti G. Torre S. Brükner L. Malpezzi V. R. Kostyanovsky R. G. Kostyanovsky 《Russian Chemical Bulletin》1998,47(7):1359-1364
The1H NMR spectra ofO-derivatives of 1-hydroxy-2,2-bis(trifluoromethyl)aziridine containing such substituents as EtO2CCH2, (R/S)-RO2CCH(Me) (R=Me, Pri, or But), (R/S)-H2NC(O)CH(Me), and (R)-H2NC(O)CH(Me) were analyzed. Both of the diastereomerically pure amides of the latter type were isolated. The validity of the1H NMR criteria, which were suggested for the determination of absolute configurations of diastereomers ofN-alkoxyaziridines, was confirmed by X-ray diffraction study of the (R,R)-amide. 相似文献
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G.V. Shustov S.N. Denisenko I.I. Chervin N.L. Asfandiarov R.G. Kostyanovsky 《Tetrahedron》1985,41(23):5719-5731
The twisting of 5- and 6-membered rings in bicyclic cis-diaziridines—1,5-diazabicyclo [3.1.0]hexanes 12–17 and l,6-diazabicyclo[4.1.0]heptane 18—is a rapid process in the time scale of 1H- and 13C-NMR even at -80°. According to the 1H- and 13C-NMR spectra, 1,5-diazabicyclo [3.1.0]hexanes 12,13,15a,15b and 16a,16b do, exist mostly in the boat form ; only the introduction of endo substituents into position 3 or 6 leads to the population of the chair, as is the case with 14 and 17. 2,4-Dialkyl substituted 1,5-diaza- and 1,3,5-triazabicyclo[3.1.0]hexanes are formed via a transition cyclization state similar in its geometry to the initial chair-shaped N-chlorodi(tri)azanes. 相似文献
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Remir G. Kostyanovsky Vladimir F. Rudchenko Oleg A. Dyachenko Ivan I. Chervin Aleksandr B. Zolotoi Lev O. Atovmyan 《Tetrahedron》1979,35(2):213-224
trans-Stereospecificity of the amidation of 1-alkoxyisoxazolidine-3,3-dicarboxylic ester (1) has been elucidated. Alkaline hydrolysis of monester 4 yielded the salt 6 which after its ion exchange in the form of S(?) and R-(+)-phenylethylammonium salts was completely separated into the enantiomeric salts (+10 and ?10). Esterification and amidation of these salts afforded antipodes 2 S-( +12) and 2 R-( ?12) containing only a nitrogen asymmetric center. Optical purities of the products were established on the basis of their NMR spectra with shift-reagent. Molecular and crystal structure as well as an absolute configuration of +10 were detected by means of X-ray analysis. 相似文献
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K. F. Koehler H. Zaddach A. D. Kuntsevich V. N. Voznesenskii I. I. Chervin R. G. Kostyanovsky 《Russian Chemical Bulletin》1993,42(10):1757-1759
The1H and13C NMR spectral parameters of α-, β-, and y-lewisites1–5 were obtained and a new isomer,cis,trans,trans-γ-lewisite5, was isolated and identified on the basis of chemical shifts, relative intensities of the signals, and the intra-chain (3
J
hh
,3
J
ch
) and interchain (3
J
casch
) coupling constants.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1833–1835, October, 1993. 相似文献
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