[C:1]([C:4]1[C:9]([O:10][CH2:11][CH2:12][CH2:13][C:14]([O:16][CH2:17][CH3:18])=[O:15])=[C:8]([CH2:19][CH2:20][CH3:21])[C:7]([S:22]C(=O)N(C)C)=[CH:6][CH:5]=1)(=[O:3])[CH3:2].[OH-].[K+].S(=O)(=O)(O)O>C(O)C>[C:1]([C:4]1[C:9]([O:10][CH2:11][CH2:12][CH2:13][C:14]([O:16][CH2:17][CH3:18])=[O:15])=[C:8]([CH2:19][CH2:20][CH3:21])[C:7]([SH:22])=[CH:6][CH:5]=1)(=[O:3])[CH3:2]Ethyl 4-(6-acetyl-3-(N,N-dimethylcarbamoylthio)-2-propylphenoxy)butyrate (10.6 g) and potassium hydroxide (4.5 g) in ethanol (100 ml) were heated with stirring under refluxing for 1.5 hours. Ice water and conc. sulfuric acid were added thereto (pH 1), and then the mixture was subjected to extraction. The organic layer was washed with water and aqueous solution of sodium chloride, followed by being dried over sodium sulfate and then concentrated under a reduced pressure. To the resultant residue was added a mixture of ethanol (30 ml) and conc. sulfuric acid (0.5 ml), and the mixture was heated with stirring and refluxing for 1.5 hours. Ice water was added thereto and the mixture was extracted with ethyl acetate. The organic layer was washed with water and thereafter was dried over sodium sulfate, followed by being concentrated under a reduced pressure. Ethyl 4-(6-acetyl-3-mercapto-2-propylphenoxy)butyrate (7.8 g, 89.7%) was obtained as brown oil.
Wird geladen…
