Аннотация
1. N-Methylpyrazoles, which have both electron-donor and electron-acceptor substituents in the 3 or (and) 5 positions, undergo oxidative iodination by I2-HIO3 mixture. Here the halogen atom can be inserted successively in the 4 position and then in either the free 5 or 3 position. 2. N-Methylpyrazole-4-carboxylic acids and 4-aldehydes under the conditions of this reaction undergo substitutive iodination and form either the 4-iodo or polyiodo derivatives. 3. The presence of moderately strong electron-acceptor substituents (I, COOCH3) in the 4 position of the pyrazole ring does not exclude the possibility of oxidative iodination in its other positions. Strong acceptor groups (NO2) in the 4 position prevent the reaction.
Язык оригинала | Английский |
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Страницы (с-по) | 778-784 |
Число страниц | 7 |
Журнал | Bulletin of the Academy of Sciences of the USSR Division of Chemical Science |
Том | 29 |
Номер выпуска | 5 |
DOI | |
Состояние | Опубликовано - 1 мая 1980 |
Опубликовано для внешнего пользования | Да |
ASJC Scopus subject areas
- Chemistry(all)