Hydrochloric Acid → (2-Iodo-5-(trifluoromethyl)phenyl)methanol

Participants

Reaction Steps

Borane-THF (1.0M solution in THF; 94 mL; 94 mmol) was added to a stirred solution of 2-iodo-5-(trifluoromethyl)benzoic acid (2.97 g; 9.4 mmol) in THF (300 mL) at 0° C. under N2. The reaction was heated at reflux for 90 min and then carefully quenched with 6N HCl until no further gas evolution. The reaction was diluted with H2O (250 mL) and extracted with EtOAc (3×250 mL). The combined extracts were washed with brine (300 mL), dried over MgSO4, filtered, and concentrated in vacuo. The crude material was purified by flash chromatography (0-25% EtOAc/hexanes gradient) to afford [2-iodo-5-(trifluoromethyl)phenyl]methanol as a white solid. LCMS=285.0 (M−17)+. 1H NMR (CDCl3, 500 MHz): δ 7.97 (d, J=8.3 Hz, 1 H), 7.79 (s, 1 H), 7.28 (d, J=8.4 Hz, 1 H), 4.75 (s, 2 H). An alternative procedure is as follows: To a solution of 2-Iodo-5-(trifluoromethyl)benzaldehyde (EXAMPLE 80, Step A, 9 g) in THF (100 mL) and water (10 mL) at 0° C. was added NaBH4 (0.5 g). The reaction was stirred 30 minutes. To the reaction mixture was added dilute aqueous HCl (cautiously). The mixture was extracted with ether and the ether layer was washed with water, then brine. The ether layer was then dried over anhydrous MgSO4, filtered and concentrated. The material is chromatographed on SiO2 using a step gradient of 1:3 CH2Cl2/hexanes, then 1:1 CH2Cl2/hexanes, then 100% CH2Cl2 to afford [2-iodo-5-(trifluoromethyl)phenyl]methanol as a white solid.

Provenance & Evidence