Dimethylformamide → (5-Fluoropyridin-2-yl)methanol

Participants

Reaction Conditions

Reaction Steps

At −78° C. under nitrogen, add n-butyllithium (2.5 M in hexane, 16.4 mL, 40.9 mmol) via syringe to a solution of 2-bromo-5-fluoro-pyridine (6.0 g, 34.1 mmol) in toluene (220 mL), while keeping the reaction temperature below −60° C. Stir the mixture at −78° C. and then add DMF (3.4 mL, 44.3 mmol) and stir for 1 h at this temperature. Warm to −10° C. and quench with methanol (10 mL). Concentrate the mixture to half of the volume in vacuo. Dilute with methanol (150 mL), cool the mixture to −78° C. and add sodium borohydride (3.2 g, 85.2 mmol) portion wise over 5 min. Warm the mixture to ambient temperature and stir for 2 h. Quench with water (10 mL) and remove the organic solvent in vacuo to obtain an oil/water mixture. Extract with diethyl ether (3×100 mL), dry the combined organic extracts, wash with brine, dry and concentrate in vacuo to obtain the desired intermediate as an oil (3.9 g, 91%).

Provenance & Evidence