[Br:1][C:2]1[CH:18]=[CH:17][C:5]([O:6][C:7]([F:16])([F:15])[CH:8]2[CH2:13][CH2:12][C:11](=[O:14])[CH2:10][CH2:9]2)=[CH:4][CH:3]=1.[BH4-].[Na+]>C(O)C>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([O:6][C:7]([F:15])([F:16])[C@H:8]2[CH2:9][CH2:10][C@H:11]([OH:14])[CH2:12][CH2:13]2)=[CH:17][CH:18]=1To a stirred solution of 4-[(4-bromo-phenoxy)-difluoro-methyl]-cyclohexanone (1050 mg, 3.290 mmoles) in ethanol (16.4 mL, 0.2M) was added NaBH4 (249 mg, 6.58 mmoles) 0° C. The solution was stirred at 0° C. for 20 minutes and then warmed to room temperature for 20 minutes. The reaction was quenched with 1N HCl to a pH of ˜7, and extracted three times with ethyl acetate. The organics where combined, dried over magnesium sulfate, filtered and concentrated. Cis/trans isomers were then separated by chiral purification. Isolated 260 mg of trans isomer (24%). 1H NMR (400 MHz, METHANOL-d4) δ ppm 1.39 (s, 2H) 1.51-1.65 (m, 2H) 1.83-1.96 (m, 2H) 2.01-2.21 (m, 2H) 2.38-2.47 (m, 1H) 7.03-7.14 (m, 2H) 7.41-7.58 (m, 2H)
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