Вид документа : Статья из журнала Шифр издания : 54/S 10 Автор(ы) : Kozhevnikov D. N., Kovalev I. S., Prokhorov A. M., Rusinov V. L., Chupakhin O. N. Заглавие : S-N(H) reactions of pyrazine N-oxides and 1,2,4-triazine 4-oxides with CH-active compounds [Electronic resource] Место публикации : Russian Chemical Bulletin (Translation of Izvestiya Akademii Nauk, Seriya Khimicheskaya). - 2003. - Vol. 52, № 7. - С. 1588-1594 Систем. требования: http://www.springerlink.com/content/m32010303x433843/fulltext.pdf Примечания : 27.10.2011 г. ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Nucleophilic substitution of hydrogen in pyrazine N-oxides under the action of CH-active compounds requires activation with acylating agents. This activation facilitates aromatization of intermediate H adducts via elimination of the acid residue to form substituted pyrazines. More electrophilic 1,2,4-triazine 4-oxides react with carbanions derived from CH-active compounds without additional activation according to a scheme, which has previously been unknown for azine N-oxides. This scheme involves aromatization of H adducts through elimination of water by the E1cb mechanism. The reaction products occur in DMSO-d6 solutions predominantly as 6-methylene-1,6-dihydropyrazines and 5-methylene-4,5-dihydro-1,2,4-triazines.??nucleophilic substitution of hydrogen - 1,2,4-triazine 4-oxide - pyrazine 1-oxide - carbanion - CH-active compounds?? Держатели документа: Центральная научная библиотека УрО РАН Доп.точки доступа: Kozhevnikov, D. N.; Kovalev, I. S.; Prokhorov, A. M.; Rusinov, V. L.; Chupakhin, O. N.