反应详情

Pyridine-2,3-diol (38 g, 342.04 mmol) was added to a solution of potassium hydroxide (21 g, 374.26 mmol) in methanol (400 mL) in portions while maintaining the reaction temperature below 30° C. Benzyl bromide (64.4 g, 376.53 mmol) was then added dropwise with stirring to the reaction mixture at room temperature. The resulting solution was stirred at 40° C. for 5 hr then concentrated in vacuo. The residue was diluted with water (500 mL) and the mixture was extracted with of dichloromethane (2×500 mL). The combined organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. Recrystallization from ethanol afforded the title compound (30 g, 43%) as a white solid: 1H NMR (400 MHz, DMSO) delta 11.60 (s, 1H), 7.45-7.28 (m, 5H), 6.96-6.89 (m, 2H), 6.10-6.06 (m, 1H), 5.01 (s, 2H).

1. temperaturewhile maintaining the reaction temperature below 30° C
2. stirringThe resulting solution was stirred at 40° C. for 5 hr
3. concentrationthen concentrated in vacuo
4. additionThe residue was diluted with water (500 mL)
5. extractionthe mixture was extracted with of dichloromethane (2×500 mL)
6. dry with materialThe combined organic layer was dried over anhydrous sodium sulfate
7. concentrationconcentrated in vacuo
8. customRecrystallization from ethanol