[CH:1]1([C:6]2[CH:14]=[CH:13][C:9]([C:10]([O-])=[O:11])=[CH:8][C:7]=2[C:15]([F:18])([F:17])[F:16])[CH2:5][CH2:4][CH2:3][CH2:2]1.[Li+].[BH4-].Cl>O1CCOCC1>[CH:1]1([C:6]2[CH:14]=[CH:13][C:9]([CH2:10][OH:11])=[CH:8][C:7]=2[C:15]([F:16])([F:17])[F:18])[CH2:2][CH2:3][CH2:4][CH2:5]1To a solution of 4-cyclopentyl-3-(trifluoromethyl)benzoate (224 g, 823 mmol) in 1,4-dioxane (600 mL), LiBH4 (494 mL, 987 mmol, 2 M solution in THF) was added dropwise at 22° C. The resulting suspension was stirred at 85.5° C. for 5.5 h. The dark brown solution was cooled to 0° C. and the pH adjusted to 5 by slowly adding 6 N HCl (130 mL). The layers were separated and to the aqueous phase H2O (250 mL) and NaCl (20 g) added. The combined aqueous were extracted with EtOAc (2×250 mL). The EtOAc layer was added to the previously separated organic phase and the combined organics were concentrated under reduced pressure. The resulting suspension was filtered through a pad of Celite/Na2SO4 and the solids were washed with EtOAc (3×400 mL). The combined organics were rotary evaporated and the dark brown oily residue was subjected to chromatography on silica to give the title compound as colorless liquid (110 g). LCMS m/z=243.3 [M−H]+; NMR (400 MHz, CDCl3) δ ppm 1.67-1.55 (m, 2H), 1.82-1.69 (m, 2H), 1.95-1.83 (m, 2H), 2.19-2.04 (m, 2H), 3.39 (quintet, J=8.0 Hz, 1H), 4.72 (s, 2H), 7.55-7.46 (m, 2H), 7.62 (s, 1H).
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