反应详情

To a solution of (R)-4-methyldihydrofuran-2-one (1.68 g in 40 mL dioxane) were added 5.51 g 3,5-dimethylbenzoic acid methyl ester followed by 1.82 g sodium hydroxide and the mixture heated to reflux on an oil bath. After 3 hours, the mixture was cooled to room temperature and the pH neutralized by the addition of 0.5N hydrochloric acid. The mixture was then extracted with ethyl acetate and the organic portion washed with brine and dried over sodium sulfate. Purification of the concentrate by flash chromatography on silica gel (hexane:ethyl acetate, 9:1) gave the title compound (2.42 g).

1. temperaturethe mixture heated
2. temperatureto reflux on an oil bath
3. extractionThe mixture was then extracted with ethyl acetate
4. washthe organic portion washed with brine
5. dry with materialdried over sodium sulfate
6. customPurification of the
7. concentrationconcentrate by flash chromatography on silica gel (hexane:ethyl acetate, 9:1)