Reaktion #47533

Reaktionsgleichung

3-chloro-but-2-enoic acid ethyl ester

Potassium t-butoxide

3-bromo-phenol

→

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

Ausbeute 39.0%

Lösungsmittel

tetrahydrofuran

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction mixture was heated
2. 2
   Temperaturto reflux for 0.75 h
3. 3
   TemperaturThe reaction mixture was refluxed for an additional 3 h
4. 4
   EinengenAfter this time, the mixture was concentrated in vacuo
5. 5
   workup.ADDITIONthe residue was diluted with water
6. 6
   Extraktionextracted with diethyl ether
7. 7
   WaschenThe organic layer was then washed with 5% aqueous sodium hydroxide solution
8. 8
   Trocknendried over sodium sulfate
9. 9
   Einengenconcentrated in vacuo

Vorschrift

Potassium t-butoxide (10.5 g, 0.094 mol) was added to a stirred solution of 3-bromo-phenol (8.18 g, 0.047 mol) in tetrahydrofuran (30 mL) at 23° C. under nitrogen and the reaction mixture was heated to reflux for 0.75 h. The reaction mixture was cooled to 23° C. and a solution of 3-chloro-but-2-enoic acid ethyl ester (prepared as in Example 191, 7.00 g, 0.047 mol) in tetrahydrofuran (40 mL) was added to the reaction mixture. The reaction mixture was refluxed for an additional 3 h. After this time, the mixture was concentrated in vacuo and the residue was diluted with water and extracted with diethyl ether. The organic layer was then washed with 5% aqueous sodium hydroxide solution followed by a saturated aqueous sodium chloride solution, dried over sodium sulfate and concentrated in vacuo to afford (E)-3-(3-bromo-phenoxy)-but-2-enoic acid ethyl ester (5.20 g, 39%) as a yellow oil.

Quelle