تفاعل #47344

معادلة التفاعل

3-(4-methoxy-phenoxy)-but-2-enoic acid ethyl ester

N-bromosuccinimide

benzoyl peroxide

→

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

المردود 78.4%

المذيبات

carbon tetrachloride

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe reaction was then heated
2. 2
   درجة الحرارةto reflux for 5 h
3. 3
   أخرىAt this time, the reaction was removed from the freezer
4. 4
   أخرىThe resulting precipitate was removed by filtration
5. 5
   غسيلwas rinsed with carbon tetrachloride (5 mL)
6. 6
   تركيزThe filtrate was concentrated in vacuo
7. 7
   أخرىPurification by Analogix flash chromatography (40 g, 1-4% ethyl acetate/hexanes)

الإجراء التجريبي

A solution of 3-(4-methoxy-phenoxy)-but-2-enoic acid ethyl ester (0.98 g, 4.17 mmol) in carbon tetrachloride (23.2 mL) was treated with N-bromosuccinimide (0.81 g, 4.59 mmol) and benzoyl peroxide (81 mg, 0.33 mmol). The reaction was then heated to reflux for 5 h. At this time, the reaction was cooled to 25° C. and then was 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 and was rinsed with carbon tetrachloride (5 mL). The filtrate was concentrated in vacuo. Purification by Analogix flash chromatography (40 g, 1-4% ethyl acetate/hexanes) afforded impure 4-bromo-3-(4-methoxy-phenoxy)-but-2-enoic acid ethyl ester (1.03 g, 78%) as a pale, yellow oil. The material was used without further purification.

المصدر