Sodium borohydride → [4-Bromo-2-(trifluoromethoxy)phenyl]methanol

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 4-bromo-2-(trifluoromethoxy)benzaldehyde (5.0 g, 19 mmol) from Step 1 above in EtOH (100 mL) at 0° C. was added NaBH4 (0.88 g, 23 mmol). The mixture was stirred for 1 h at 0° C., the cooling bath was removed, and the solution was stirred at ambient temperature for 14 h. The solvent was removed under reduced pressure and the residue was partitioned between EtOAc (150 mL) and saturated aqueous NaHCO3 (75 mL). The organic phase was separated, dried (MgSO4), filtered, and the solvent was removed under reduced pressure. The residue was purified by pressurized silica gel column chromatography using a gradient elution of 5-10% EtOAc:hexanes. 4-Bromo-2-(trifluoromethoxy)benzyl alcohol was obtained as an amorphous solid by evaporation from CH2Cl2 (TLC Rf =0.25 (10% EtOAc:hexanes); HPLC retention time=8.8 min (method A)).

Provenance & Evidence