N-bromobutanimide → Methyl 2-(bromomethyl)-3-fluorobenzoate

Participants

Reaction Steps

A solution of 3-fluoro-2-methyl-benzoic acid methyl ester (3.64 g, 21.67 mmol) in carbon tetrachloride (100 mL) was treated with N-bromosuccinimide (3.85 g, 21.63 mmol) and benzoyl peroxide (0.1 g). The reaction mixture was then heated at reflux temperature and after 3 h the heat was removed and it was stirred at room temperature over the weekend. The reaction was then filtered to remove the solids and concentrated in vacuo to yield a light yellow oil. The reaction was then repeated with the remaining 3-fluoro-2-methyl-benzoic acid methyl ester (6.1 g, 36.3 mmol) in carbon tetrachloride using N-bromosuccinimide (6.5 g, 36.5 mmol) and benzoyl peroxide (0.1 g) heating at reflux. The reaction mixture was then filtered and concentrated in vacuo. The two material from the two reactions was combined and purified by flash column chromatography (silica gel, 10% diethyl ether/hexanes) to afford 2-bromomethyl-3-fluoro-benzoic acid methyl ester (14.22 g, 99%) as a white solid.

Provenance & Evidence