[OH-].[Li+].[CH2:3]([O:5][CH:6]([CH2:12][C:13]1[CH:18]=[CH:17][C:16]([O:19][CH2:20][CH:21]=[C:22]2[C:34]3[CH:33]=[CH:32][CH:31]=[CH:30][C:29]=3[C:28]3[C:23]2=[CH:24][CH:25]=[CH:26][CH:27]=3)=[CH:15][CH:14]=1)[C:7]([O:9]CC)=[O:8])[CH3:4]>C(O)C>[CH2:3]([O:5][CH:6]([CH2:12][C:13]1[CH:18]=[CH:17][C:16]([O:19][CH2:20][CH:21]=[C:22]2[C:34]3[CH:33]=[CH:32][CH:31]=[CH:30][C:29]=3[C:28]3[C:23]2=[CH:24][CH:25]=[CH:26][CH:27]=3)=[CH:15][CH:14]=1)[C:7]([OH:9])=[O:8])[CH3:4]Lithium hydroxide (1M, 1.0 ml, 1.0 mmol) was added to a suspension of ethyl 2-ethoxy-3-[4-(2-fluoren-9-ylidene-ethoxy)-phenyl]-propionate (0.214 g, 0.5 mmol) in ethanol (5 ml) and the resulting mixture heated to gentle reflux for 30 min. The cooled mixture was partitioned between water (30 ml) and dichloromethane (20 ml), acidified to pH 1 by adding 1N hydrochloric acid (3 ml), and the organic phase collected. The aqueous phase was further extracted with dichloromethane (3×20 ml) and the combined organics were washed with brine, dried (MgSO4) and evaporated to give a yellow gum. The product was purified by column chromatography on silica gel (3% methanol in dichloromethane eluent) to give 2-ethoxy-3-[4-(2-fluoren-9-ylidene-ethoxy)-phenyl]-propionic acid, as a yellow solid; 0.104 g (51%).
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