反应详情

7-(2-Chlorophenyl)-7-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-2,2-dimethylheptanoic acid ethyl ester (2.80 g, 7.23 mmol) was dissolved in ethanol (40 mL) and water (25 mL) containing potassium hydroxide (10 g, 250 mmol). The mixture was heated to reflux for 24 hours. After 24 hours, the flask was cooled to room temperature and concentrated. Water (50 mL) was added and extracted with 10% ethyl acetate in heptane. The aqueous fraction was acidified (to pH=6) with concentrated hydrochloric acid and the product was extracted with dichloromethane (2×100 mL). The dichloromethane extracts were combined, dried over sodium sulfate, filtered and concentrated. The remaining tan oil (3.0 g) was purified by flash column chromatography on silica gel (100 g), eluting with heptane-ethyl acetate (2:1) to provide 7-(2-chlorophenyl)-7-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-2,2-dimethylheptanoic acid as a white solid (2.1 g, 71.6% yield). The product was dissolved in water (ASTM 1, 200 mL) containing hydrochloric acid (1%) and acetone (25 mL). Most of the acetone and excess hydrochloric acid was removed under reduced pressure. The remaining water (200 mL) was freeze-dried to provide 7-(2-chlorophenyl)-7-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-2,2-dimethylheptanoic acid, hydrochloride salt (Compound Ig hydrochloride, 2.2 g, mp 97-100° C., 99.47% purity by HPLC) as a white solid. 1H NMR (300 MHz, DMSO-d6): δ=12.25 (br s, 0.5H), 12.12 (br s, 0.5H), 8.24 (br s, 1H), 7.60-7.38 (m, 4H), 6.94 (d, 1H, J=4.5 Hz), 6.77 (d, 1H, J=4.5 Hz), 4.90-4.68 (m, 1.5H), 4.38 (dd, 0.5H, J=14.4, 5.4 Hz), 4.01 (m, 1H), 3.80 (dd, 0.5H, J=14.4, 5.1 Hz), 3.60-3.30 (m, 1.5H), 3.20-2.85 (m, 2H), 2.42 (m, 1H), 2.23 (m, 1H), 1.40-1.0 (m, 5H), 1.01 (s, 6H), 0.79 (m, 1H). (mixture of rotational isomers). 13C NMR (75 MHz, DMSO-d6): δ=178.41, 134.70, 134.60, 131.83, 131.49, 131.23, 131.05, 129.93, 129.75, 128.38, 128.35, 128.10, 125.43, 125.26, 124.87, 124.86, 64.35, 63.17, 49.87, 48.70, 48.00, 47.13, 41.16, 30.78, 30.30, 30.12, 25.77, 25.02, 24.14, 21.78, 21.37. (mixture of rotational isomers). HRMS (MMI-TOF): Calculated for C22H29Cl2NO2S (MH+): 406.1202. found 406.1594.

1. temperatureThe mixture was heated
2. temperatureto reflux for 24 hours
3. concentrationconcentrated
4. additionWater (50 mL) was added
5. extractionextracted with 10% ethyl acetate in heptane
6. extractionthe product was extracted with dichloromethane (2×100 mL)
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customThe remaining tan oil (3.0 g) was purified by flash column chromatography on silica gel (100 g)
11. washeluting with heptane-ethyl acetate (2:1)