[NH2:1][C@@:2]([C:8]1[CH:13]=[C:12]([Br:14])[CH:11]=[CH:10][C:9]=1[F:15])([CH3:7])[C:3](OC)=[O:4].[H-].[Al+3].[Li+].[H-].[H-].[H-].O.[OH-].[Na+].[O-]S([O-])(=O)=O.[Na+].[Na+]>C(OCC)C>[NH2:1][C@@:2]([C:8]1[CH:13]=[C:12]([Br:14])[CH:11]=[CH:10][C:9]=1[F:15])([CH3:7])[CH2:3][OH:4]To a solution of (R)-methyl 2-amino-2-(5-bromo-2-fluorophenyl)propanoate (3.95 g, 14.3 mmol, Eq: 1.00) in diethyl ether (120 ml) was added at 0° C. lithium aluminum hydride (652 mg, 17.2 mmol, Eq: 1.2) in five portions. The icebath was removed and stirring continued at room temperature for 2 hours. To the cooled reaction mixture was added dropwise water (652 mg, 652 μl, 36.2 mmol, Eq: 2.53), NaOH (15% in water) (572 mg, 652 μl, 14.3 mmol, Eq: 1.00) and water (1.96 g, 1956 μl, 109 mmol, Eq: 7.59) via syringe (1:1:3 system) and the mixture was stirred for 20 min until a white suspension occurred. Three small spoons of Na2SO4 were added to the mixture, which was filtered after 5 min. The colourless ether solution was evaporated to give (R)-2-amino-2-(5-bromo-2-fluorophenyl)propan-1-ol (3.2 g, 12.9 mmol, 90.2% yield) as a white solid which was used in the next step without further purification. MS (ISP): m/z=248.1 [M+H]+ and 250.0 [M+2+H]+.
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