反応 #47332

反応方程式

3-(3-chloro-2-fluoro-phenoxy)-but-2-enoic acid ethyl ester

N-bromosuccinimide

benzoyl peroxide

→

4-bromo-3-(3-chloro-2-fluoro-phenoxy)-but-2-enoic acid ethyl ester

収率 86.4%

溶媒

carbon tetrachloride

反応条件

後処理

1. 1
   温度The reaction was then warmed
2. 2
   温度to reflux for 5 h
3. 3
   その他At this time, the reaction was removed from the freezer
4. 4
   その他The resulting precipitate was removed by filtration
5. 5
   濃縮The filtrate was concentrated in vacuo
6. 6
   その他Purification by Analogix flash chromatography (40 g, 1-10% ethyl acetate/hexanes)

実験手順

A solution of 3-(3-chloro-2-fluoro-phenoxy)-but-2-enoic acid ethyl ester (1.41 g, 5.45 mmol) in carbon tetrachloride (30 mL) was treated with N-bromosuccinimide (1.07 g, 6.01 mmol) and benzoyl peroxide (0.15 g). The reaction was then warmed to reflux for 5 h. At this time, the reaction was cooled to 25° C. and then placed in the freezer over the weekend. At this time, the reaction was removed from the freezer and allowed to thaw. The resulting precipitate was removed by filtration. The filtrate was concentrated in vacuo. Purification by Analogix flash chromatography (40 g, 1-10% ethyl acetate/hexanes) afforded impure 4-bromo-3-(3-chloro-2-fluoro-phenoxy)-but-2-enoic acid ethyl ester (1.59 g, 86%) as a white solid. The material was used without further purification.

出典