反应详情

3-Hydroxy-2-methyl-4-pyrone (25 g, 0.198 mol) was dissolved in 70 ml of DMF. To the solution was added 8.7 g (0.218 mol) of sodium hydride (60% in mineral oil). The mixture was stirred under ice cooling for 30 min. Benzyl bromide (37.3 g, 0.218 mol) was added dropwise to the reaction solution under ice cooling, and a reaction was allowed to proceed at room temperature overnight. The reaction solution was poured into ice water, followed by extraction with ethyl acetate. The organic layer was washed with water, and was dried over anhydrous sodium sulfate. The solvent was removed by distillation under the reduced pressure. The reddish brown oil thus obtained (64 g) was applied to column chromatography on silica gel (Wako Gel C-200, n-hexane-ethyl acetate) to give 41.6 g (yield 97%) of 3-benzyloxy-2-methyl-4-pyrone.

1. waitto proceed at room temperature overnight
2. extractionfollowed by extraction with ethyl acetate
3. washThe organic layer was washed with water
4. dry with materialwas dried over anhydrous sodium sulfate
5. customThe solvent was removed by distillation under the reduced pressure
6. customThe reddish brown oil thus obtained (64 g)