Benzoyl Peroxide → (E)-4-bromo-3-(2,3-dimethoxy-phenoxy)-but-2-enoic acid ethyl ester

Participants

Reaction Steps

To a stirred mixture of (E)-3-(2,3-dimethoxy-phenoxy)-but-2-enoic acid ethyl ester (4.20 g, 0.016 mol) in carbon tetrachloride (25 mL) under a nitrogen atmosphere was added N-bromosuccinimide (4.22 g, 0.024 mol) and benzoyl peroxide (380 mg, 0.002 mol). Nitrogen gas was bubbled through the mixture for 5 min, and the resulting mixture was heated to reflux for 4 h. The reaction mixture was then placed in the refrigerator overnight. The solids formed were removed by filtration and the filtrate concentrated in vacuo. The crude product obtained was purified using flash column chromatography (silica gel (100-200 mesh), ethyl acetate/hexanes) to afford (E)-4-bromo-3-(2,3-dimethoxy-phenoxy)-but-2-enoic acid ethyl ester (3.10 g, 57%) as a yellow oil.

Provenance & Evidence