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931.
I. A. Zyryanova L. V. Baikalova O. A. Tarasova A. V. Afonin V. A. Kukhareva M. A. Maksimova B. A. Trofimov 《Russian Journal of General Chemistry》2005,75(8):1283-1289
With respect to Co2+, Ni2+, Zn2+,Cd2+, Cu2+, Pd2+, and Sn4+ salts, 1-isopropenyl-substituted imidazole, 2-methylimidazole, and pyrazole behave as monodentate ligands with only one coordination center on the N1 and N2 atoms, respectively; 1-isopropenylpyrazole under complex-formation conditions is dealkylated to form pyrazole complexes. The reaction with HCl leaves the unsaturated substituent in 1-isopropenylimidazole intact and yields corresponding hydrochlorides by the N3 atom of the heterocycle. The least basic 1-isopropenylpyrazole takes up HCl also by the double bond of the alkenyl group. 相似文献
932.
Betaines are formed in good yields in the reaction of N-heteroaromatic compounds with 2-dicyanomethyleneindane-1,3-dione oxide and its 4- and 5-halo derivatives in dioxane. The corresponding oxides were obtained by oxidation of 2-dicyanomethyleneindane-1,3-dione and its 4- and 5-substituted derivatives with hydrogen peroxide in dioxane. Data from the IR spectra of the compounds are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 889–892, July, 1978. 相似文献
933.
934.
Russian Chemical Bulletin - 相似文献
935.
936.
937.
The photo-reaction of phenol (1) with chloroform in the presence of diethylamine gave salicylaldehyde (2) and 4-hydroxybenzaldehyde (3) in fair yield. Dihydroxybenzenes, sensitive to alkali, under similar conditions without the base gave corresponding aldehydes and a cyclohexa-2,5-dienone (15). The photo-reaction was also applied to diethylaniline (18), indoline (21) and N-methylindoline (24). In carbon tetrachloride instead of chloroform in an alcohol solution the same type of reaction took place to give esters. The mechanism involving the coupling of a phenoxy radical or a radical cation with dichloromethyl radical and not involving dichlorocarbene is proposed. 相似文献
938.
939.
940.
I. I. Chuev S. M. Aldoshin O. A. Kozina A. D. Dubonosov E. N. Shepelenko V. A. Bren' V. I. Minkin 《Russian Chemical Bulletin》1992,41(12):2230-2233
X-ray structural analysis was used to determine the molecular and crystal structure of 2-(N-benzyl-N-phenylhydrazinoethylidene)-3-(2H)-benzo[b]thiophenone. The crystals are monoclinic, the space group isC2/c,a=16.022(6),b=11.202(3),c=22.111(4) Å, =81.08(3)°, and andZ=8. It was shown that the ability of hydrazones of a similar class to exhibit photochromic properties is a function of the steric stresses in the molecules and their confirmation.Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2805–2809, December, 1992. 相似文献