Potassium Hydroxide → Ketoprofen

Participants

Reaction Steps

Water (4 ml) was added to a mixture consisting of 269 mg of methyl α-methylthio-α-[m-(α,α-dimethoxybenzyl)phenyl]propionate, 500 mg of zinc powder and 80 mg of copper sulfate pentahydrate. Then, 500 mg of potassium hydroxide (85%) was added, and the mixture was stirred at the refluxing temperature for 44 hours. Water (4 ml) was further added, and with stirring, the mixture was heated under reflux for 3 hours. After cooling, the insoluble matter was separated by filtration, and washied with 20 ml of water. The filtrate and the washing were combined and adjusted to pH 1 with 2.0 ml of conc. hydrochloric acid. The mixture was stirred at 60° C. for 40 minutes and then, extracted three times with 20 ml of diethyl ether. The extract was washed with 10 ml of water, and dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was chromatographed on a silica gel column using methylene chloride as an eluent to afford 162 mg of α-(m-benzoylphenyl) propionic acid in a yield of 85%.

Provenance & Evidence