[BH4-].[Na+].[Br:3][C:4]1[CH:17]=[CH:16][C:7]([O:8][C@@H:9]([CH3:15])[C:10](OCC)=[O:11])=[CH:6][CH:5]=1>C(O)C>[Br:3][C:4]1[CH:17]=[CH:16][C:7]([O:8][C@@H:9]([CH3:15])[CH2:10][OH:11])=[CH:6][CH:5]=1Sodium borohydride (1.15 g) was added to a solution of (2S)-2-(4-bromophenoxy)propionic acid, ethyl ester (7.5 g, Example 4a)) in ethanol (20 ml) at 5° C. The resulting solution was allowed to attain room temperature and was stirred for 10 hours before being concentrated under reduced pressure. The residue was partitioned between ethyl acetate (100 ml) and 2M hydrochloric acid (50 ml). The mixture was extracted into ethyl acetate and the combined extracts were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The product was used directly in the next step without further purification (6.32 g).
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