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Earlier1 it was reported that 4-aryl-4,5-dihydrothiophene-1,1-dioxides (I) are converted in aqueous and alcohol solution of bases to isomeric 3-aryl-2,5-dihydrothiophene dioxides (II) and 3-aryl-4,5-dihydrothiophene-1,1-dioxides (III) (Fig. 1).In the presence of electron-donor substituents in the p-position of the phenyl ring, IIb, c compounds are practically irreversibly isomerised to III b, c. For unsubstituted phenyldihydrothiophene-1,1-dioxides IIa and IIIa the reaction proceeds riversibly but equilibrium is shifted towards isomer IIIa indicating its high thermodynamic stability. It is known2 that 2,5-dihydrothiophene-1,1 -dioxide is more stable than 4,5-dihydrothiophene-1,1-dioxide. Consequently, the observed stability increase of 3-aryl-4,5-dihydrothiophene-1,1-dioxides (IIIa–c) is due to interaction of the substituent C6H4X with the sulfonyl group. This paper investigates the nature of this interaction. 相似文献
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A. P. Polishchuk I. Yu. Polishchuk G. V. Klimusheva A. V. Gridyakina A. B. Bordyug L. G. Grineva 《Crystallography Reports》2005,50(3):415-418
The crystal structure of N,N′-di(2-carboxyethyl)-4,4′-dipyridylium diperchlorate, C16H18Cl2N2O12, is determined using X-ray diffraction analysis at 293 K. The crystals are orthorhombic, a = 20.084(4) Å, b = 8.687(2) Å, c = 11.725(2) Å, space group Pna21, and Z = 4; 1688 reflections measured; and R = 0.056 and R w = 0.059 for 1244 reflections with I > 3σ(I). It is found that, in the absence of charge transfer or short intramolecular O?N contacts, the nucleus of the dication adopts a twist conformation (the angle of rotation between the planes of the pyridine rings is equal to 23°). 相似文献
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T. É. Bezmenova G. V. Klimusheva V. I. Kulishov S. M. Lukashov G. G. Rodé G. M. Soroka V. P. Tantsyura 《Chemistry of Heterocyclic Compounds》1977,13(8):848-851
The peculiarities of the intramolecular interaction in unsaturated five-membered cyclic sulfones as a function of their structures were studied on the basis of an analysis of the electronic absorption spectra of single crystals of isomeric -aryldihydrothiophene 1,1-dioxides at 4.2°K, the IR spectra of the molecules at 298°K, and the results of x-ray diffraction analysis of 3-phenyl-4,5-dihydrothiophene 1,1-dioxide. In addition to the inductive effect, conjugation of the SO2 group with the -electron system of 3-phenyl-4,5-dihydrothiophene 1,1-dioxide, which is manifested most appreciably in the excited electronic state, was observed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1056–1059, August, 1977. 相似文献
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The consequences of spin-orbit coupling in p-dihalogenobenzenes for solvent-induced shifts or S1 ← S0 spectral transitions, and for changes of S1-state vibrational frequencies compared with the S0 state, are assigned to mixing low-energy triplet states into the singlet-state system. 相似文献
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G. V. Klimusheva 《Theoretical and Experimental Chemistry》1967,2(1):29-33
Interpretations are given for the electronic absorption spectra of crystals of alkylbenzenes and benzene itself; these are based on molecular models that include somewhat out-of-plane positions for the carbon atoms in the benzene ring. The relation of stability and specific properties to structure for aromatic hydrocarbons is discussed. 相似文献
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Klimusheva G Bugaychuk S Garbovskiy Y Kolesnyk O Mirnaya T Ishchenko A 《Optics letters》2006,31(2):235-237
Recordings of dynamic holograms with microsecond relaxation times under the action of nanosecond laser pulses are obtained in composites on the base of a novel class of liquid crystals (LCs) in ionic metal-alkanoates. Holographic parameters and relaxation characteristics are measured for doped lyotropic ionic LC, for sandwichlike cells (consisting of a dye layer and a layer of the lyotropic ionic LC), and for colored ionic smectic glasses. The structure of the materials is investigated by use of the small-angle x-ray technique. The mechanism of resonance nonlinearity in photosensitive centers and mechanisms of the grating erasure connected with a charge transport in the ionic conductive LC matrix are discussed. 相似文献