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1.
1. | Carbonyls of iron and manganese initiate addition of CHCl3. and CCl4, at the C-Cl bond to , -dichloroallyl acetate. The adduct-radicals formed [CCl2CH(R)CH2OCOCH3 (R= CHCl2, CCl3)] are stabilized mainly by H atom abstraction (from CHCl3 or the medium) with formation of the compounds HCCl2CH(R)CH2OCOCH3. The system Fe(CO)5+ nucleophilic coinitiator assists the transfer of chlorine by the adduct-radical. |
2. | Under peroxide initiation only C6H5CH3 and CHCl3 add to ,-dichloroallyl acetate, which reacts by C-H bond cleavage in the chain transfer stage. |
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Conclusions The reaction of CCl4 and CHCl3 with CCl2=CHR, where R=(CH2)3H (I) and (CH2)3Cl (II), gives compounds of type HCCl2CH(CCl3)R, and the adducts HCCl2CH(CCl)2CH2CH2CH2Cl (V) from (I) and HCCl2CH·(CCl3)CH2CH2CHCl2 (VIII) from (II).From CCl4 and CC12=CHCH2CH2CH=CH2, besides the usual addition product CCl2=CHCH2CH2CHClCH2· CCl3, is formed 1,1-dichloro-2-(trichIoromethyl)-5-(chloromethyl)cyclopentane due to stabilization of the CCl2CH(CCl3)R radical by intramolecular addition to the CH=CH2 group and the subsequent cleavage of chlorine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1569–1574, July, 1975. 相似文献
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An important problem of molecular biophysics is the influence of pH and ionic strength of a solution on chemical structures and charge of biologically active substances. By means of pH titration and Raman spectroscopy methods, the influence of solution acidity on structural changes of actinocin derivatives was investigated, analogues to antitumor antibiotic actinomycin D. It has been shown that these ligands have different values of cation charges in neutral solutions. From analysis of Raman spectra, it was concluded that protonation of nitrogen atom and amino group of the phenoxazone ring starts only at pH < 3.5. It was shown that protonation of actinocin derivative with two amide groups (diaminoactinocin) occurred in two steps. Corresponding protonation constants for diaminoactinocin (log k 1 = 6.9 ± 0.5 and log k 2 = 5.3 ± 0.1) and for partially protonated actinocin derivative with three methylene groups in the side chains (log k = 5.3 ± 0.1) were obtained. Characteristic frequencies of Raman spectra for the basic functional C=O, C2–NH2, C–C=C, and –N=C groups of phenoxazone chromophore of actinocin derivatives in protonated and nonprotonated states were determined. The different affinities of binding of variously charged ligands to DNA have also been demonstrated. 相似文献
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The possibility of preparing highly dispersed mixed zirconium-aluminum oxides by precipitation of zirconium hydroxide on γ-Al2O3 was studied. 相似文献
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N. V. Kruglova 《Russian Chemical Bulletin》1967,16(5):1132-1133
Conclusions The anhydrides of phenyl- and p-tolylboronic acid react with dicyclohexyl peroxydicarbonate at 60–65° in solution with the formation of aryl radicals. Tribenzylborine behaves in a similar manner. The transformation products of the aryl and benzyl radicals were identified.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1163–1164, May, 1967. 相似文献
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