反应详情

To a solution of potassium hydroxide (1.57 g, 28 mmol) in water (1.5 mL) and absolute ethanol (5 mL) was added 3-{3-[3-(2-ethoxycarbonyl-2-methyl-propyl)-benzoyl]-phenyl}-2,2-dimethyl-propionic acid ethyl ester (4.38 g, 10 mmol) in portions. The mixture was heated to reflux for 3 h and the ethanol was distilled off under reduced pressure on a water-bath. The residual aqueous solution was extracted with chloroform (2×50 mL), then cooled with an ice-bath, and acidified with hydrochloric acid to pH 1. The mixture was extracted with diethyl ether (3×50 mL). The ethereal extracts were dried over sodium sulfate and concentrated in vacuo to give 3-{3-[3-(2-carboxy-2-methylpropyl)benzoyl]-phenyl}-2,2-dimethyl-propanoic acid (3.88 g, 100%) as a solid. Mp.: 46-48° C. 1H NMR (300 MHz, CDCl3): δ (ppm): 7.8-7.2 (m, 8H), 2.83 (s, 4H), 1.25 (s,12H). 13C NMR (75 MHz, CDCl3): δ (ppm): 198.02, 184.0, 139.2, 137.3, 134.5, 129.5, 128.4, 128.3, 127.6, 43.8, 24.7. HRMS (LSIMS, gly): Calcd. for C23H27O5 (MH+): 383.1858, found: 383.1858.

1. temperatureThe mixture was heated
2. temperatureto reflux for 3 h
3. distillationthe ethanol was distilled off under reduced pressure on a water-bath
4. extractionThe residual aqueous solution was extracted with chloroform (2×50 mL)
5. temperaturecooled with an ice-bath
6. extractionThe mixture was extracted with diethyl ether (3×50 mL)
7. dry with materialThe ethereal extracts were dried over sodium sulfate
8. concentrationconcentrated in vacuo