تفاعل #47274

معادلة التفاعل

(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

المردود 113.0%

المذيبات

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةthe resulting solution heated
2. 2
   درجة الحرارةto reflux for 23 h
3. 3
   workup.ADDITIONwas added
4. 4
   أخرىThe mixture was separated
5. 5
   غسيلthe organic phase washed with a 20% sodium chloride solution (19 L)
6. 6
   أخرىThe solution was evaporated

الإجراء التجريبي

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.

المصدر