反応 #9666

反応方程式

N-(3,5-difluorophenyl) thiourea

bromine

→

5,7-difluoro-1,3-benzothiazol-2-amine

収率 90.7%

溶媒

DCE

DCE

反応条件

後処理

1. 1
   温度The mixture was heated
2. 2
   温度at reflux for 2.5 h
3. 3
   その他the precipitate formed
4. 4
   ろ過was collected by filtration
5. 5
   洗浄washed with DCE
6. 6
   ろ過filtered
7. 7
   その他dried in a vacuum oven

実験手順

To a suspension of N-(3,5-difluorophenyl) thiourea (3.40 g, 18.07 mmol) in DCE (95 mL) was added a solution of bromine in DCE (5 mL) below 30° C. The mixture was heated at reflux for 2.5 h, then cooled to 10° C., and the precipitate formed was collected by filtration and washed with DCE. The solid was stirred with water (200 mL), basified by treatment with conc. ammonium hydroxide, filtered, and dried in a vacuum oven to afford 5,7-difluoro-1,3-benzothiazol-2-amine (3.05 g, 90%). ret. time 2.18; m/z 187.1 (NH+); 1H NMR (400 MHz, DMSO-d6) δ 6.92 (m, 1H), 7.00 (m, 2H), 7.92 (s, 2H).

出典