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The photochemical chlorination of 2-trichloromethyl-1,3-dioxolane proceeds only at the carbon atoms in the 4 and 5 positions. The structures of the resulting 2-trichloromethyl-4-chloro-and 2-trichloromethyl-4,5-dichloro-1,3-dioxolanes were proved by means of the IR spectra and chemical transformations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1611–1613, December, 1973.  相似文献   

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The reaction of hexamethyldisiloxane with 2-ethoxy-1,3-dioxolane is described. It is shown that cleavage of the endo- and exocyclic carbon-oxygen bonds of the ortho ester occurs under mild conditions (16–20C) in the presence of acidic catalysts with the formation of 2-(trimethylsiloxy)ethyl formate, the subsequent transformation of which leads to ethyl formate, trimethylethoxysilane, and 1,2-bis(trimethylsiloxy)ethane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1607–1611, December, 1989.  相似文献   

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A convenient approach for the preparation of (4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane is described. The target compound via two steps is synthesized from diethyl-2,3-O-isobutylidene-D-tartrate, through ammonolysis and reduction.  相似文献   

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Chloral cyanomethylhemiacetal is converted to 2-trichloromethyl-4-imino-1,3-dioxolane under the influence of hydrogen chloride or pyridine. Acetone cyanohydrin reacts with chloral to give 2-trichloromethyl-4-imino-5,5-dimethyl-1,3-dioxolane, the hydrochloride of which in water gives 2-trichloromethyl-4-oxo-5,5-dimethyl-1,3-dioxolane.  相似文献   

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Copolymerization of 2-vinyl-1,3-dioxane with styrene and 1,3-dioxolane was carried out in methylene chloride at 0°C with triethyloxonium tetrafluoroborate as an initiator. Random copolymers were obtained from both of these monomer pairs, but attempted copolymerization of 2-vinyl-1,3-dioxane with 3,3-bis(chloromethyl)oxetane under similar conditions resulted in the homopolymer of the latter monomer. There were three structural units of 2-vinyl-1,3-dioxane in these copolymers as in its homopolymer: the “ester” unit, which was formed by vinyl addition with hydride shift followed by ring-opening rearrangement, the “vinyl” unit produced by ring-opening reaction, and the unit with a pendant 1,3-dioxane ring formed by simple vinyl addition. The fractions of the ester and vinyl units to the total 2-vinyl-1,3-dioxane units in the copolymer of 2-vinyl-1,3-dioxane with styrene decreased with decreasing 2-vinyl-1,3-dioxane content. On the contrary, the fraction of the vinyl unit in the copolymer of 2-vinyl-1,3-dioxane with 1,3-dioxolane increased slightly with decreasing 2-vinyl-1,3-dioxane content, while that of the ester unit decreased. The reactivities of the propagating species are discussed on the basis of these results.  相似文献   

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Conclusion The addition of 2-trichloromethyl-l,3-dioxolane to vinyltrimethylsilane upon initiation by a system consisting of Fe(CO)5 and a nucleophilic cocatalyst proceeds to cleavage of a C-Cl bond in the trichloromethyl group with the formation of an adduct containing the dioxolanyl ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2351–2353, October, 1986.  相似文献   

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Conclusions Vinyltrimethylsilane in radical reactions with a cyclic acetal gives 2- and 4-substituted 1,3-dioxolanes together with telomers of linear structure. Increasing the concentration of the monomer and reducing the reaction temperature favors an increase in the proportion of cyclic telomers.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1616–1620, July, 1986.  相似文献   

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Speeds of sound of the ternary mixtures cyclohexane+1,3-dioxolane+2-butanol and n-hexane+1,3-dioxolane+2-butanol have been measured at the temperatures of 298.15 and 313.15 K. Isentropic compressibilities and excess isentropic compressibilities have been calculated from experimental data. We have also compared the experimental isentropic compressibilities with calculated values from the free length theory and the collision factor theory. Experimental results show positive values of excess isentropic compressibilities in almost the whole composition range for the ternary mixture containing cyclohexane, meanwhile they are negative for the mixture containing n-hexane. Such different behaviour of these systems is related to the large free volume shown by n-hexane. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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