C[O:2][C:3](=[O:23])[CH:4]([C:11]1[CH:16]=[CH:15][C:14]([S:17][CH3:18])=[C:13]([C:19]([F:22])([F:21])[F:20])[CH:12]=1)[CH2:5][CH:6]1[CH2:10][CH2:9][CH2:8][CH2:7]1.[OH-].[Li+]>O1CCCC1.O.O>[CH:6]1([CH2:5][CH:4]([C:11]2[CH:16]=[CH:15][C:14]([S:17][CH3:18])=[C:13]([C:19]([F:22])([F:20])[F:21])[CH:12]=2)[C:3]([OH:23])=[O:2])[CH2:10][CH2:9][CH2:8][CH2:7]1A solution of 3-cyclopentyl-2-(4-methylsulfanyl-3-trifluoromethyl-phenyl)-propionic acid methyl ester (prepared as in Example 89, 1.73 g, 5 mmol) in tetrahydrofuran/water (20 mL, 3:1) was treated with lithium hydroxide (419 mg, 10 mmol). The reaction was stirred at 25° C. for 24 h. At this time, the reaction was diluted with water (50 mL) and extracted with ether (1×50 mL). The aqueous layer was acidified to pH=2 with a 2N aqueous hydrochloric acid solution. The product was extracted into methylene chloride (3×75 mL). The combined organic layers were washed with a saturated aqueous sodium chloride solution (3×100 mL), dried over magnesium sulfate and sodium sulfate, filtered, and concentrated in vacuo. The residue was triturated with 90/10 hexanes/ether to afford 3-cyclopentyl-2-(4-methylsulfanyl-3-trifluoromethyl-phenyl)-propionic acid (1.05 g, 63.65%) as a white solid: mp 105-106° C.; EI-HRMS m/e calcd for C16H19F3O2S (M+) 332.1058, found 332.1055.
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