反应 #9667

反应方程式

HCl

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

isoamyl nitrite

→

2-chloro-5,7-difluoro-1,3-benzothiazole

收率 48.0%

溶剂

—

tri(ethylene glycol) dimethyl ether

acetonitrile

acetonitrile

反应条件

后处理

1. 1
   workup.STIRRINGThe reaction mixture was stirred at rt for 10 minutes
2. 2
   温度heated at 50° C. for 2.5 h
3. 3
   温度The reaction mixture was cooled to rt
4. 4
   萃取The solution was extracted with EtOAc
5. 5
   洗涤The organic layer was washed with HCl (1.0 M), water and brine
6. 6
   过滤filtered
7. 7
   浓缩concentrated
8. 8
   其他The residue was purified by flash chromatography (Biotage Flash 40M)

实验过程

To a solution containing copper chloride (H) (0.89 g, 6.64 mmol) and tri(ethylene glycol) dimethyl ether (6 mL) in acetonitrile (60 mL) was added isoamyl nitrite (0.97 g, 8.30 mmol) and the reaction mixture was stirred at rt for 30 minutes. To this suspension was added dropwise a solution of 5,7-difluoro-1,3-benzothiazol-2-amine (1.03 g, 5.53 mmol) in tri(ethylene glycol) dimethyl ether (20 mL) and acetonitrile (30 mL). The reaction mixture was stirred at rt for 10 minutes and heated at 50° C. for 2.5 h. The reaction mixture was cooled to rt, and then poured cautiously into cold aqueous 6 M HCl (400 mL). The solution was extracted with EtOAc. The organic layer was washed with HCl (1.0 M), water and brine, filtered, and concentrated. The residue was purified by flash chromatography (Biotage Flash 40M) using 5% ethyl acetate in hexane to afford 2-chloro-5,7-difluoro-1,3-benzothiazole (0.55 g, 48%). 1H NMR (400 MHz, CD2Cl2) 7.02 (m, 1H), 7.52 (m, 1H).

来源