[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[C@H:8]([CH:12]([CH3:14])[CH3:13])[C@:7]([CH2:16][C:17]([O:19]C(C)(C)C)=[O:18])([OH:15])[CH2:6][CH2:5]2.C(O)=O>O>[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[C@H:8]([CH:12]([CH3:14])[CH3:13])[C@:7]([CH2:16][C:17]([OH:19])=[O:18])([OH:15])[CH2:6][CH2:5]2A mixture of 3.02 g crude tert-butyl (1S,2S)-(6-fluoro-2-hydroxy-1-isopropyl-1, 2,3,4-tetrahydronaphthalen-2-yl)acetate and 8 mL 96% formic acid was stirred at 25° C. for four hours. The solution was diluted with 6 mL water; then heated to 75° C and filtered. The filtrate was slowly cooled to 25° C. with stirring. The resulting suspension was cooled to 0° C., stirred for one hour, and suction filtered. The precipitate was washed with 15 mL water, air dried at 25° C. for one hour, then oven dried at 50° C. for 22 hours to give 1.59 g (1S,2S)-(6-fluoro-2-hydroxy-l-isopropyl-1, 2,3,4-tetrahydronaphthalen-2-yl)acetic acid as a colorless solid, m.p. 102-103.5° C., [α]D27 = 78.80° (CHCl3).
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