Water → 3-(3,4-Dimethoxy-phenyl)-propynoic acid

反応式

[OH-].[K+].O.C([O:6][C:7](=[O:22])[CH:8](Br)[CH:9](Br)[C:10]1[CH:15]=[CH:14][C:13]([O:16][CH3:17])=[C:12]([O:18][CH3:19])[CH:11]=1)C>C(O)C>[CH3:19][O:18][C:12]1[CH:11]=[C:10]([C:9]#[C:8][C:7]([OH:22])=[O:6])[CH:15]=[CH:14][C:13]=1[O:16][CH3:17]

参加物

反応条件

温度: 10 °C

実験手順

To a solution of 52.7 g (0.80 mol) of potassium hydroxide (85%) in 300 ml of ethanol and 30 ml of water 59.4 g (0.15 mol) of 2,3-dibromo-3-(3,4-dimethoxyphenyl)propionic acid ethyl ester are added at 25° C. over 10 minutes. The mixture is stirred under reflux for 2.5 hours. The solvent is evaporated, the residue dissolved in 200 ml of water and, with cooling to 10° C., the solution acidified with 2N hydrochloric acid. The resulting crystals are filtered off, washed with water and recrystallized from methanol/water.