反应详情

To a solution of 1,4,4,5,5-pentamethylimidazolidin-2-one (14 mg; 0.091 mmol) in dry tetrahydrofuran (0.2 ml), a 1.57 N solution of n-butyl lithium in hexane (0.06 ml; 0.1 mmol) was added at 0° C. After 5 minutes, a solution of 2-bromopropionyl bromide (24 mg; 0.11 mmol) in dry tetrahydrofuran (0.1 ml) was added thereto at the same temperature and followed by stirring for 10 minutes. A phosphate buffer (pH 7.0) was added to decompose the excess reaction agent. The aqueous layer was extracted with ethyl acetate, and the combined organic layers were successively washed with a 5% aqueous solution of sodium bicarbonate and brine and dried over anhydrous magnesium sulfate. After removal of the solvent under reduced pressure, the residue was purified by preparative thin layer chromatography (benzene:ethyl acetate=5:1) to give 3-(2'-bromopropionyl)-1,4,4,5,5-pentamethylimidazolidin-2-one.

1. extractionThe aqueous layer was extracted with ethyl acetate
2. washthe combined organic layers were successively washed with a 5% aqueous solution of sodium bicarbonate and brine
3. dry with materialdried over anhydrous magnesium sulfate
4. customAfter removal of the solvent under reduced pressure
5. customthe residue was purified by preparative thin layer chromatography (benzene:ethyl acetate=5:1)