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J. Karolak-Wojciechowska R. CzylkowskiZ. Karczmarzyk M.H. PaluchowskaB. Rys E. SznelerM.J. Mokrosz 《Journal of Molecular Structure》2002,612(1):39-47
The X-ray crystal structures of series of 1-aryl-1,4-dihydro-3(2H)-isoquinolinones (1-7) have been determined. Lactame heterocyclic ring possesses more or less deformed boat conformation in all examined structures. The aryl substituent adopts the equatorial position in the structures 1-3 and the axial one in 5-7. In the structure of 4, due to extremely flattened heterocyclic ring, aryl substituent location can be named as bisectional. In all solved structures the molecules are joined into the dimers via two N-H?O hydrogen bonds. At the same time, 1H NMR studies in DMSO-d6 solutions were accomplished and profound analysis of 2J, 3J, and 5J coupling constants have shown that in isoquinolinone system the heterocyclic ring adopts the boat conformation in all investigated compounds. The stereochemical orientations of the phenyl ring at C1 do not depend on the nature of the substituent but, exclusively, on the mode of substitution. However, three forms of undulated laktam heterocyclic ring conformation in respect of 1-aryl substituent positions were confirmed by calculation (conformational analysis). 相似文献
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Jerzy Lange Elzbieta Pytlewska Jan Plenkiewicz Tomasz Kulinski Janina Karolak-Wojciechowska Slawomir Rump 《Journal of heterocyclic chemistry》1997,34(2):389-396
Ethoxycarbonylalkylidene derivatives 2 and 6 of the title hydrazones were obtained in the reaction with ethyl pyruvate or ethyl aroylformate and ethyl acetoacetate, respectively, in methanol. Both compounds were mixtures of geometric isomers with high predominance of one of them. Nmr spectroscopy revealed an unexpected magnetic non-equivalence of the CH2 protons in the ester ethyl group of the major isomer of 6 . On heating (?200°) in an inert medium or on refluxing in ethanolic sodium ethoxide 2 cyclized to the corresponding pyridazino[6,1-c]-triazines 4 , whereas 6 formed pyrazolylpyridazines 7 . The structure of the latter was unambigously established by X-ray analysis. Alkylation of 4a with benzyl bromide in the presence of tetrabutylammonium bromide occurred selectively on the pyridazine N atom. 相似文献
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Olczak-Kobza M. Czylkowski R. Karolak-Wojciechowska J. 《Journal of Thermal Analysis and Calorimetry》2003,74(3):895-904
Mixed complexes of the type: Zn(Hsal)2(Him)2, Zn(Hsal)2(Him)5, Zn(Hsal)2(4-MeHim)2 and Zn(Hsal)2(1,2-diMeim)2 (where Hsal=OHC6H4COO-, Him=imidazole, 4-MeHim=4-methylimidazole, 1,2-diMeim=1,2-dimethylimidazole) have been synthesized. The application of chemical, thermal and X-ray methods has enabled us to analyze
the complexes and their sinters. The gaseous products of pyrolysis of Zn(Hsal)2(Him)2 and Zn(Hsal)2(4-MeHim)2 have been investigated. Thermal decomposition pathways have been postulated for synthesized complexes. The molecular structures
of the Zn(Hsal)2(Him)2 and Zn(Hsal)2(1,2-diMeim)2 have been solved. 相似文献
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W. Kwiatkowski J. Karolak-Wojciechowska M. W. Wieczorek 《Journal of chemical crystallography》1988,18(5):517-523
C20H22O4,M
r
=326.39, triclinic,P¯1,a=10.365(2),b=11.383(2),c=8.461(1) Å, =103.60(1),=104.44(1), =105.23(1)°,Z=2, (CuK)=1.54178 Å;R=0.0633 for 1940 reflections. The results of the X-ray analysis have shown that the ethyl carboxylate substituent is oriented. The geometry of the main skeleton of the molecule has not revealed any significant differences in the present compound and in the case of the epimeric molecule. 相似文献
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