R 59 Ring-chain isomerism of ethyl 7-polyfluoroalkyl-7-hydroxy-4,7-dihydro[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylates [] / M. V. Pryadeina, Ya. V. Burgart, V. I. Saloutin, O. N. Chupakhin // Mendeleev Communications. - 2008. - Vol. 18, № 5. - С. 276-277. - Bibliogr. : p.277 (10 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Cyclisation of ethyl 2-ethoxymethylidene-3-oxo-3-polyfluoroalkylpropionates with 3-amino-1H-[1,2,4]triazole gives ethyl 7-polyfluoroalkyl-7-hydroxy-4,7-dihydro[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylates that are subject to ring–chain isomerisation in solution, depending on the solvent and the length of the polyfluoroalkyl substituent, to yield ethyl 3-polyfluoroalkyl-3-oxo-2-{([1,2,4]triazol-3-yl)aminomethylidene}propionates via heterocyclic ring opening at the C(7)–N(8) bond \\\\Expert2\\nbo\\Mendeleev Communications\\2008, v.18, p.276.pdf |