반응 #47274

반응 방정식

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

N-bromosuccinimide

water

→

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

수율 113.0%

용매

dichloromethane

반응 조건

후처리

1. 1
   온도the resulting solution heated
2. 2
   온도to reflux for 23 h
3. 3
   workup.ADDITIONwas added
4. 4
   기타The mixture was separated
5. 5
   세척the organic phase washed with a 20% sodium chloride solution (19 L)
6. 6
   기타The solution was evaporated

실험 절차

To a solution of (E)-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester (1880 g, 7.82 mol) in dichloromethane (18.6 L) was added N-bromosuccinimide (1490 g, 8.29 mol) and 2,2′-azobis(2,4-dimethylvaleronitrile) (47 g, 0.188 mol) and the resulting solution heated to reflux for 23 h. The light yellow solution was cooled to room temperature and transferred to an extractor before water (19 L) was added. The biphasic mixture was stirred at room temperature for 1 h. The mixture was separated and the organic phase washed with a 20% sodium chloride solution (19 L). The solution was evaporated to give (E)-4-bromo-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester (87.8% pure by HPLC, 2824 g, 99%) as a red oil.

출처