反应详情

Methyl α-methylthio(m-benzoylphenyl)acetate (713 mg) was dissolved in 6 ml of anhydrous dimethylformamide, and with ice cooling, 100 mg (65% content) of sodium hydride was added. The mixture was stirred for 30 minutes. The reaction mixture turned black violet. When 0.3 ml of methyl iodide was added with ice cooling, the color vanished immediately. The mixture was stirred for 10 minutes at room temperature, and then an aqueous solution of ammonium chloride (500 mg/30 ml) was added. The mixture was extracted three times with 20 ml of diethyl ether. The organic layer was washed three times with 10 ml of water, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was chromatographed on a silica gel column using benzene and methylene chloride as eluents to give 111 mg of methyl α-methylthio-α-(m-benzoylphenyl)propionate and 461 mg of a mixture which was shown by NMR analysis to consist of methyl α-methylthio(m-benzoylphenyl)acetate and methyl α-methylthio-α-(m-benzoylphenyl)propionate (the mole ratio=7:11).

1. stirringThe mixture was stirred for 10 minutes at room temperature
2. extractionThe mixture was extracted three times with 20 ml of diethyl ether
3. washThe organic layer was washed three times with 10 ml of water
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe residue was chromatographed on a silica gel column