[NH2:1][C:2]([CH2:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)([CH:7]([F:9])[F:8])[C:3](OC)=[O:4].[BH4-].[Li+].Cl>C1COCC1>[NH2:1][C:2]([CH:7]([F:8])[F:9])([CH2:10][C:11]1[CH:12]=[CH:13][CH:14]=[CH:15][CH:16]=1)[CH2:3][OH:4]To a solution of methyl 2-amino-2-benzyl-3,3-difluoropropanoate (0.11 g, 0.48 mmol) (for synthesis see: Bey et al, J. Org. Chem. 1979, 44, 2732-2742) in 6.8 mL THF was added lithium borohydride (2M in THF, 1.45 mL, 2.9 mmol) dropwise. The reaction was heated at reflux temperature for 2 h, quenched with MeOH and acetone and concentrated. Hydrochloric acid (1M, 14.5 mL, 14.5 mmol) was added, the mixture was heated to 45° C. for 1.5 h and concentrated. The reaction was made basic with saturated NaHCO3 and extracted with CHCl3. Drying and solvent evaporation gave 2-amino-2-(difluoromethyl)-3-phenylpropan-1-ol. 1H NMR (400 MHz, CDCl3) δ 7.35-7.24 (m, 5H), 5.67 (t, J=56.5 Hz, 1H), 3.56 (A of AB, d, J=11.0 Hz, 1H), 3.46 (B of AB, d, J=11.0 Hz, 1H), 2.89 (A of AB, d, J=13.6 Hz, 1H), 2.84 (B of AB, d, J=13.6, 1H).
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