反应详情

10 mmol of 5-(3,4-dimethoxyphenyl)-2oxazolidinone is dissolved in 20 ml. of absolute dimethylformamide and combined with 11 mmol of sodium hydride. The mixture is then stirred for 40 minutes at 40°. After cooling, 20 mmol of methyl iodide in 5 ml. of dimethylformamide is added dropwise and thereafter the reaction mixture is agitated for 6 hours at 50°. After the dimethylformamide has been removed by evaporation, the mixture is taken up in chloroform and then washed first with a small amount of water and then with saturated sodium chloride solution, dried, filtered, and concentrated. The residue is chromatographed over 60 g. of silica gel with chloroform/methanol (96:4) as the eluent. Recrystallization from ethanol produces a 60% yield of 5-(3,4-dimethoxyphenyl)-3-methyl-2-oxazolidinone, m.p. 132°-133°.

1. temperatureAfter cooling
2. stirringthe reaction mixture is agitated for 6 hours at 50°
3. customAfter the dimethylformamide has been removed by evaporation
4. washwashed first with a small amount of water
5. dry with materialwith saturated sodium chloride solution, dried
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue is chromatographed over 60 g
9. customRecrystallization from ethanol