反应详情

Under nitrogen atmosphere, 2-methoxy-1-(2,4,6-trihydroxyphenyl)ethanone (60 mg, 303.03 mmol), anhydrous potassium carbonate powder (250.9 g, 1.82 mmol), TBAB (tetrabutyl ammonium bromide, 145.9 mg, 454.52 mmol) and 4-fluorobenzoyl chloride (95.8 mg, 606 mmol) were dissolved in toluene (1200 mL), and refluxed for 6 hours. After cooling, toluene was removed, and then water (500 mL) was added. The aqueous solution was extracted with dichloromethane. The combined organic phase was washed with water and saturated brine, and dried over anhydrous sodium sulfate. A brown residue was obtained after removal of solvent. The residue was dissolved in a 5% potassium carbonate aqueous solution and heated to reflux for 2 hr. After cooling to ambient temperature, the mixture was acidified to pH 6 with 1N HCl solution, and extracted with dichloromethane three times. The combined organic phase was dried over anhydrous sodium sulfate, and the solvent was removed. The crude product was purified by silica gel column chromatography (eluent:ethyl acetate/petroleum ether, 1:5) and recrystallized in ethanol to give the desired compound (75 g, yield 81.9%).

1. temperaturerefluxed for 6 hours
2. temperatureAfter cooling
3. customtoluene was removed
4. additionwater (500 mL) was added
5. extractionThe aqueous solution was extracted with dichloromethane
6. washThe combined organic phase was washed with water and saturated brine
7. dry with materialdried over anhydrous sodium sulfate
8. customA brown residue was obtained
9. customafter removal of solvent
10. dissolutionThe residue was dissolved in a 5% potassium carbonate aqueous solution
11. temperatureheated
12. temperatureto reflux for 2 hr
13. extractionextracted with dichloromethane three times
14. dry with materialThe combined organic phase was dried over anhydrous sodium sulfate
15. customthe solvent was removed
16. customThe crude product was purified by silica gel column chromatography (eluent:ethyl acetate/petroleum ether, 1:5)
17. customrecrystallized in ethanol