Q 32 Quaternization of pyrido[2,3-b]pyrazines: 1H and 13C NMR Study [Electronic resource] / O. N. Chupakhin, V. N. Charushin, A. I. Chernyshev, S. E. Esipov // Magnetic Resonance in Chemistry. - 1985. - Vol. 23, № 6. - С. 437-441. - Bibliogr. : p. 441 (20 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): N-METHYLPYRIDO[2,3-B]PYRAZINIUM SALTS -- PYRIDO[2,3-b]PYRAZINES Аннотация: The structure of N-methylpyrido[2,3-b]pyrazinium salts has been examined by 1H and 13C NMR. 6-Dimethylamino- and 6-morpholino-pyrido[2,3-b]pyrazines were shown to undergo quaternization by methyl iodide at N-4 of the pyrazine ring, whereas the pyridine ring N-5 was the N-alkylation site in the reaction of unsubstituted pyrido[2,3-b]pyrazine with methyl iodide under the same conditions. The effects of quaternization on the 1H and 13C chemical shifts and the nJ(CH) values are discussed. \\\\expert2\\nbo\\Magnetic Resonance in Chemistry\\1985, v.23, N 6, p.437.pdf |