G 65 Goryaeva, M. V. Synthesis of pyrimido[1,2-alfa]benzimidazoles from ethyl 2-ethoxymethylidene-3-oxo-3-(polyfluoroalkyl)propionates [Electronic resource] / M. V. Goryaeva, Ya. V. Burgart, V. I. Saloutin // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2010. - Vol. 46, № 3. - P432-438 : рис., табл. - Bibliogr. : p. 438 (22 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): BENZIMIDAZOLES -- ETHYL -- PROPIONATES Аннотация: Cyclization of ethyl 2-ethoxymethylidene-3-oxo-3-polyfluoroalkylpropionates with benzimidazol-2-amine in boiling 1,4-dioxane followed two concurrent pathways with participation of fluoroacyl and ethoxycarbonyl fragments and formation of, respectively, ethyl 4-hydroxy-4-polyfluoroalkyl-1,4-dihydropyrimido-[1,2-alfa]benzimidazole-3-carboxylates and 3-polyfluoroacylpyrimido[1,2-alfa]benzimidazol-4-ols. Dihydropyrimido[1,2-alfabenzimidazole derivatives undergo dehydration to give ethyl 4-(polyfluoroalkyl)pyrimido[1,2-alfa]benzimidazole-3-carboxylates, whereas the hydroxy group in 3-polyfluoroacylpyrimido[1,2-a]benzimidazol-4-ols is capable of being replaced by the amino group of the second benzimidazole molecule with formation of 4-(1H-benzimidazol-2-ylamino)-3-polyfluoroacylpyrimido[1,2-alfa]benzimidazoles. \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2010, 46 (3), 432-438.pdf |