Reaction Steps
To a solution of 2,3-dihydro-6-methoxy-2-(4-methoxyphenyl)benzo[b]thiophene-3-carboxylic acid methyl ester (0.7337 g, 2.21 mmol) in methanol (10 ml) at 5° C. was added 5 N sodium hydroxide (1 ml, 5 mmol) and water (5 ml). The resulting slurry was stirred at that temperature for 1 hour, then toluene (5 ml) was added, and the resulting mixture was stirred at room temperature for 16 hours. Additional 5 N sodium hydroxide (1 ml) was then added, and the mixture stirred an additional 16 hours. The reaction mixture was then diluted with water (5 ml) and diethyl ether (20 ml), and the layers separated. The aqueous layer was acidified to pH 1 with 1 N hydrochloric acid, and extracted with diethyl ether (2×50 ml). The ether layers were combined, dried (magnesium sulfate), filtered and concentrated to a foam, which was further dried in vacuo to afford 0.6146 g (88%) of title compound. IR (KBr) 3300-2800 (br), 2836, 1710, 1611, 1594, 1514, 1482, 1248, 1181, 1030 cm-1 ; 1H NMR (CDCl3): δ11.63 (br s, 1 H), 7.37 (d, 2 H, J=8.4 Hz); 7.24 (d, 1 H, J=8.4 Hz), 6.85 (d, 2 H, J=8.4 Hz), 6.78 (d, 1 H, J=2.2 Hz), 6.67 (dd, 1 H, J=8.4, 2.2 Hz), 5.38 (d, 1 H, J=7.5 Hz), 4.42 (d, 1 H, J=7.5 Hz), 3.79 (s, 6 H); 13C NMR (CDCl3): d 177.7, 160.7, 159.5, 142.8, 132.3, 128.7, 127.3, 126.0, 114.3, 111.0, 107.5, 60.3, 55.6, 55.4, 55.1. Anal. calcd. for C17H16O4S: C, 64.54; H, 5.10; S; 10.13. Found: C, 64.78; H, 5.14; S, 10.55.
