Hydrochloric Acid → 5-Bromo-2-fluoro-4-methylbenzaldehyde

Participants

Reaction Steps

To a solution of 2-bromo-5-fluorotoluene (20 g) in dry tetrahydrofuran (200 ml) was added dropwise lithium diisopropylamide (2.0 M, heptan-tetrohydrofuran-ethylbenzene solution, 52.9 ml) under argon atmosphere at −78° C. After stirring as such for 2 hours, a solution of DMF (41 ml) in dry tetrahydrofuran (50 ml) was added dropwise. The mixture was returned to room temperature and stirred for 1 hour. Then, water was added and the mixture was neutralized with 1N hydrochloric acid. After extraction with ethyl acetate, the extract was washed with saturated brine and dried with magnesium sulfate. The solvent was distilled off under reduced pressure, and the resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=24:1) and re-crystallized from hexane-ethyl acetate to give 5-bromo-2-fluoro-4-methylbenzaldehyde (9.39 g).

Provenance & Evidence