R 30 Reaction of 3-(polyfluoroacyl)chromones with hydrazines: new regioselective synthesis of RF-containing pyrazoles [Electronic resource] / V. Ya. Sosnovskikh, R. A. Irgashev, V. S. Moshkin, M. I. Kodess // Russian Chemical Bulletin (Translation of Izvestiya Akademii Nauk, Seriya Khimicheskaya). - 2008. - Vol. 57, № 10. - P2146-2155 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Reactions of 3-(polyfluoroacyl)chromones with hydrazine, methyl-and phenylhydrazines proceed by the mechanism of nucleophilic 1,4-addition with subsequent pyrone ring opening and heterocyclization at the polyfluoroacyl group to 4-(2-hydroxyaroyl)-3-polyfluoro-alkylpyrazoles or at the aroyl group to 4-polyfluoroalkyl-2,4-dihydrochromeno[4,3-c]pyrazol-4-ols. Regiochemistry of the products was established based on the data of 2D-experiments HSQC, HMBC, and NOESY and X-ray diffraction study \\\\Expert2\\nbo\\Russian Chemical Bulletin\\2008, 57 (10), 2146.pdf |