反应详情

35.5 g (0.1275 mol) of 3-fluoro-4′-methanesulphonylbenzophenone, prepared in Example 10, are added in portions to a solution of 15.7 g (0.140 mol) of potassium t-butoxide in 100 ml of t-butanol. The mixture is stirred and 32 ml (0.191 mol) of ethyl succinate are added dropwise at a rapid rate. The mixture is subsequently refluxed for 30 minutes and cooled, water and 1 N hydrochloric acid are added to bring the pH to 1 and the mixture is then extracted with t-butyl methyl ether. The organic phase is treated with 2% sodium hydroxide solution and the mixture is decanted. The aqueous phase is acidified with 1 N hydrochloric acid and then extracted with t-butyl methyl ether. The organic phase is dried over magnesium sulphate and evaporated under vacuum to give 39.2 g of 3-ethoxycarbonyl-4-(3-fluorophenyl)-4-(4-methanesulphonylphenyl)-3-butenoic acid in the form of a thick oil, which is used as such in the next step.

1. temperatureThe mixture is subsequently refluxed for 30 minutes
2. temperaturecooled
3. extractionthe mixture is then extracted with t-butyl methyl ether
4. additionThe organic phase is treated with 2% sodium hydroxide solution
5. customthe mixture is decanted
6. extractionextracted with t-butyl methyl ether
7. dry with materialThe organic phase is dried over magnesium sulphate
8. customevaporated under vacuum