反应详情

温度

40 °C

10 ml of chloroform are added to 8 g of 3-aminochromone in 200 ml of toluene and the mixture is warmed to 40° C. After cooling to 20° C., 10 ml of N,N-diisopropylethylamine are added with stirring, followed by the addition of 4.8 ml of bromoacetyl chloride in 20 ml of toluene at 10° C. in the course of 5 minutes. When the addition is complete, the reaction mixture is stirred for 1 hour at room temperature. The crystalline precipitate which has formed is collected by suction, washed with water and recrystallised from ethanol/petroleum ether, yielding 11.8 g of 2-bromo-N-(4-oxo-1-benzopyran-3-yl)-acetamide with a melting point of 198° C.

1. temperatureAfter cooling to 20° C.
2. additionWhen the addition
3. stirringthe reaction mixture is stirred for 1 hour at room temperature
4. customThe crystalline precipitate which has formed
5. customis collected by suction
6. washwashed with water
7. customrecrystallised from ethanol/petroleum ether