反应详情

Diisopropylamine (16.2 g) was dissolved in tetrahydrofuran (133 ml), and 1.6N n-butyl lithium (100 ml) was dropwise added thereto under ice-cooling. The reaction mixture was stirred at the same temperature for 10 min, and a solution of 2,4-dichloroacetophenone (25.2 g) in tetrahydrofuran (133 ml) was dropwise added under cooling in a dry ice-acetone bath. Hexamethylphosphoramide (26.7 ml) was added little by little. The mixture was stirred at the same temperature for 5 min, and chlorotrimethylsilane (20.3 ml) was dropwise added, which was followed by stirring at room temperature for 30 min. The reaction mixture was partitioned between ice-cooled n-hexane and ice-cooled water. The organic layer was washed twice with ice-cooling water and then once with saturated brine, dried over sodium sulfate and concentrated under reduced pressure to dryness to give a crude product (37.5 g) of the objective compound as a pale-yellow oil.

1. temperatureunder ice-cooling
2. temperatureunder cooling in a dry ice-acetone bath
3. stirringThe mixture was stirred at the same temperature for 5 min
4. stirringby stirring at room temperature for 30 min
5. customThe reaction mixture was partitioned between ice-
6. temperaturecooled n-hexane and ice-
7. temperaturecooled water
8. washThe organic layer was washed twice with ice-
9. temperaturecooling water
10. dry with materialonce with saturated brine, dried over sodium sulfate
11. concentrationconcentrated under reduced pressure to dryness