反应详情

To a mixed solution of 12.0 parts of sodium hydroxide, 40 parts of water and 60 parts of methanol was added dropwise under reflux 31.0 parts of ethyl 3,3-dimethyl-4,6,6,6-tetrachlorohexanoate and, after the dropwise addition had been completed, the mixture was stirred at that temperature for 2 hours. The reaction mixture was then distilled under reduced pressure to remove the methanol, and the residue was neutralized with hydrochloric acid and extracted with diethyl ether. From this ether layer was obtained 19.2 parts of 3,3-dimethyl-4-(2',2'-dichlorovinyl)-4-butanolide (yield 92%) which had the following properties.

1. additionafter the dropwise addition
2. distillationThe reaction mixture was then distilled under reduced pressure
3. customto remove the methanol
4. extractionextracted with diethyl ether