Efficient synthesis and spectroscopic analysis of 8-nitro spiro C-3-annulated 2-benzazepines and their N-oxides

Nitroderivatives 9a-g have been prepared with great C-8 regioselectivity by allowing the corresponding 1,2,4,5-tetrahydrospiro[3H-2-benzazepine-3,1′-cycloalkanes] 8a-g to react with potassium nitrate and concentrated H2SO4. The oxidative reaction of a nitrogen-carbon bond in spirobenzazepines 8 and 9 was performed with H2O2 and catalytic amounts of sodium tungstate at room temperature affording nitrones 10a-d in moderate to high yields. Stereochemical assignments for all the 2-benzazepine derivatives obtained were derived from a full analysis of the 1H NMR spectroscopic data and an X-ray crystallographic analysis of 1,5dimethyl-8-nitro-1,2,4,5-tetrahydrospiro[3H-2-benzazepine-3, 1′-cyclohexane] 9c. These data indicate that the 2-benzazepines 8-11 in solution present the azepine ring preferably in the chair conformation, with the methyl substituent at C-5 disposed equatorially.

Авторы
Varlamov A. 1 , Kouznetsov V.2 , Zubkov F. 1 , Chernyshev A. 1 , Alexandrov G. 1 , Palma A.2 , Vargas L.2 , Salas S.2
Журнал
Номер выпуска
6
Язык
Английский
Страницы
849-854
Статус
Опубликовано
Год
2001
Организации
  • 1 Department of Organic Chemistry, Russ. Peoples Friendship University, Moscow 117923, Russian Federation
  • 2 Laboratory Fine Organic Synthesis, School of Chemistry, Industrial University of Santander, A.A. 678, Bucaramanga, Colombia
Ключевые слова
2-Benzazepines; Homoallylamines; Nitrones; Regioselective nitration
Дата создания
19.10.2018
Дата изменения
13.08.2021
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/366/
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