反应详情

温度

110 °C

Kojic acid (2 g, 14.1 mmol), Cs2CO3 (4.6 g, 14.1 mmol) and DMF (12 mL) were charged in a 100 ml round-bottomed flask equipped with a magnetic stirrer. 1,5-Dibromopentane (8.1 g, 35.2 mmol) was added and the reaction mixture was stirred for 2 h at 110° C. After evaporation of DMF, the reaction mixture was poured in 50 mL of H2O, extracted with CH2Cl2 (2×100 mL). The organic layer was washed with brine (2×20 mL), dried over MgSO4, filtered and evaporated to dryness. The crude compound was purified by column chromatography (SiO2; CH2Cl2:MeOH 99:1 to 95:5) to give after evaporation 5-(5-bromopentyloxy)-2-(hydroxymethyl)-4H-pyran-4-one 10 (1.9 g, 46% yield) as a brown oil.

1. customequipped with a magnetic stirrer
2. customAfter evaporation of DMF
3. additionthe reaction mixture was poured in 50 mL of H2O
4. extractionextracted with CH2Cl2 (2×100 mL)
5. washThe organic layer was washed with brine (2×20 mL)
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. customevaporated to dryness
9. customThe crude compound was purified by column chromatography (SiO2; CH2Cl2:MeOH 99:1 to 95:5)
10. customto give