反应详情

To a solution of 1-(4-chloro-phenyl)-3-cyclopentyl-propan-1-one O-methyl-oxime (1.120 g, 4.214 mmol) in carbon tetrachloride were added N-bromosuccinimide (812 mg, 4.425 mmol) and benzoyl peroxide (102 mg, 0.4 mmol). The resulting mixture was heated at reflux for 12 h. Upon cooling to room temperature, the solids were filtered and washed with diethyl ether. The filtrate was washed with aqueous solution of sodium bicarbonate, sodium thiosulfate and brine. It was then dried with anhydrous sodium sulfate and concentrated in vacuo. Purification of the crude residue by flash chromatography (Biotage system, KP-Sil™ 32–63 μm, 60 Å silica gel) eluting with 1–2% ethyl acetate in hexanes yielded 2-bromo-1-(4-chloro-phenyl)-3-cyclopentyl-propan-1-one O-methyl-oxime (1.16 g, 80%) as yellow oil.

1. temperatureThe resulting mixture was heated
2. temperatureat reflux for 12 h
3. filtrationthe solids were filtered
4. washwashed with diethyl ether
5. washThe filtrate was washed with aqueous solution of sodium bicarbonate, sodium thiosulfate and brine
6. dry with materialIt was then dried with anhydrous sodium sulfate
7. concentrationconcentrated in vacuo
8. customPurification of the crude residue by flash chromatography (Biotage system, KP-Sil™ 32–63 μm, 60 Å silica gel)
9. washeluting with 1–2% ethyl acetate in hexanes