反応 #10497

反応方程式

7-Bromo-3-hydroxy-4H-benzo[1,4]thiazine-2-carboxylic acid ethyl ester

→

(6-bromo-benzothiazol-2-yl)-acetic acid ethyl ester

溶媒

acetic acid

反応条件

後処理

1. 1
   温度cooled to room temperature
2. 2
   ろ過Zinc was filtered off
3. 3
   洗浄rinsed with 20 mL EtOAc
4. 4
   濃縮The combined filtrate was concentrated to yellow crystals
5. 5
   その他purified by column chromatography (silica gel, 20:90 EtOAc:hexane)

実験手順

7-Bromo-3-hydroxy-4H-benzo[1,4]thiazine-2-carboxylic acid ethyl ester (2.47 g, 7.8 mmol) was dissolved in 50 mL of acetic acid and heated to 110° C. under nitrogen. Zinc powder (7.5 g, 114.7 mmol) was added in portions at room temperature over 80 minutes. The mixture was stirred at 110° C. for additional 2 hours and cooled to room temperature. Zinc was filtered off and rinsed with 20 mL EtOAc. The combined filtrate was concentrated to yellow crystals and purified by column chromatography (silica gel, 20:90 EtOAc:hexane) to give (6-bromo-benzothiazol-2-yl)-acetic acid ethyl ester.

出典