反应详情

To 9.5 g of ethyl[[6,7-dichloro-2-(1-hydroxypropyl)benzo[b]thien-5-yl]oxy]acetate in 210 ml of ethanol is added 180 ml of 6N sodium hydroxide solution and the mixture is stirred at 100° for 30 mins. The cooled mixture is concentrated in vacuo to give a white slurry which is diluted with 400 ml of ice water and 300 ml of ethyl ether. With stirring and efficient cooling, the mixture is acidified with 6N hydrochloric acid. The acidic mixture is extracted with ethyl ether. The ether extracts are washed, dried over anhydrous magnesium sulfate and evaporated to dryness. Recrystallization of the residue from ethyl ether and hexane gives 7.5 g of [[6,7-dichloro-2-(1-hydroxypropyl)benzo[b]thien-5-yl]oxy]acetic acid, mp 156°-158°.

1. concentrationThe cooled mixture is concentrated in vacuo
2. customto give a white slurry which
3. stirringWith stirring
4. extractionThe acidic mixture is extracted with ethyl ether
5. washThe ether extracts are washed
6. dry with materialdried over anhydrous magnesium sulfate
7. customevaporated to dryness
8. customRecrystallization of the residue from ethyl ether and hexane