[Br:1][C:2]1[CH:3]=[CH:4][C:5]([F:17])=[C:6]([C:8]2([CH:14]3[CH2:16][CH2:15]3)[CH2:12][O:11]C(=O)[NH:9]2)[CH:7]=1.O.[OH-].[Li+]>C(O)C.O>[NH2:9][C:8]([C:6]1[CH:7]=[C:2]([Br:1])[CH:3]=[CH:4][C:5]=1[F:17])([CH:14]1[CH2:16][CH2:15]1)[CH2:12][OH:11]A solution of the crude (RS)-4-(5-bromo-2-fluoro-phenyl)-4-cyclopropyl-oxazolidin-2-one (4.802 g) in ethanol (25 ml) and water (125 ml) was treated with lithium hydroxide monohydrate (6.7 g, 160 mmol) and the reaction mixture was stirred at 100° C. overnight. For the workup, the reaction mixture was extracted with dichloromethane, the combined organic layers were washed with water, then dried over sodium sulfate and evaporated. The crude product was purified by chromatography on an Isolute flash NH2 column using a gradient of heptane/ethyl acetate as the eluent. (RS)-2-amino-2-(5-bromo-2-fluoro-phenyl)-2-cyclopropyl-ethanol was obtained as a yellow oil (2.27 g, 52% of theory). Mass (calculated) C11H13BrFNO [274.132]; (found) [M+H]+=274, [M+2-H]+=276.
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