General procedure for the synthesis of (2-amino-4-(trifluoromethyl)phenyl)methanol from 2-amino-4-trifluoromethylbenzoic acid: representative method for the preparation of 2-amino-4-(trifluoromethyl)benzyl alcohol (17a): 2-amino-4-trifluoromethylbenzoic acid (16a, 2.04 g, 10 mmol) and NaBH4 (0.912 g, 24 mmol) were were suspended in THF (10 mL). A solution of iodine (I2, 2.54 g, 10 mmol) in THF (10 mL) was slowly added at 0°C over 10-15 min under nitrogen protection. The reaction mixture was stirred at room temperature for 30 min, followed by heating and reflux stirring for 24 hr. Upon completion of the reaction, the mixture was cooled to room temperature and MeOH was slowly added until a clarified solution was formed. The solvent was removed under reduced pressure and the residue was stirred with 20% aqueous KOH solution (20 mL) for 4 hours at room temperature. The reaction mixture was extracted with CH2Cl2 (3 x 100 mL) and the organic phase was dried with anhydrous Na2SO4 and concentrated under reduced pressure to give the target alcohol 17a (1.91 g, 100% yield).1H NMR (CDCl3, 300 MHz): δ 7.15 (d, 1H, J = 7.5 Hz), 6.94 (d, 1H, J = 7.5 Hz), 6.91 ( s, 1H), 4.71 (s, 2H).
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