反应详情

To a solution of 5-amino-4-methyl-1-[(E)-2-ethoxyvinyl]pyrazole (10.6 g) in tetrahydrofuran (212 ml) was added 4N hydrochloric acid, and the mixture was refluxed for 3 hours. The reaction mixture was adjusted to pH 8 under ice-cooling, thereto was added ethyl acetate (100 ml). The separated organic layer was dried over magnesium sulfate and evaporated in vacuo to give 7-methyl-1H-imidazo[1,2-b]pyrazole (6.92 g) as crystals. IR (Nujol) : 3100, 1620, 1500 cm-1

1. temperaturethe mixture was refluxed for 3 hours
2. temperaturecooling
3. dry with materialThe separated organic layer was dried over magnesium sulfate
4. customevaporated in vacuo