反应详情

2-Acetyl-4-cyanophenol (0.78 g, 4.84 mmol), 4-acetoxybenzoic acid (0.872 g, 4.84 mmol) and phosphorus oxychloride (0.5 mL) and pyridine (2.0 mL) were mixed in anhydrous dichloromethane (10 mL). The reaction mixture was stirred overnight at rt and then poured into cold water and extracted with dichloromethane (150 mL). The organic layer was washed with sodium bicarbonate, brine and dried over sodium sulfate followed by concentration. The crude compound (1.40 g, 89.5%) was obtained after evaporation of the solvent. The crude compound (1.4 g, 4.33 mmol) was dissolved into dry THF (20 mL) and potassium tert-butoxide (0.51 g, 4.55 mmol) was added and the reaction mixture was stirred at rt for 2 h. The solvent was removed, followed by addition of water (50 mL) and EtOAc (150 mL) was used to extract out the compound. The organic layer was washed with brine and dried over sodium sulfate. The crude product (1.20 g) and 4 drops of sulfuric acid were added to AcOH (15 mL). The reaction mixture was heated to 110° C. for 1 h. AcOH was removed and sodium bicarbonate solution was added followed by extraction with EtOAc. The organic layer was washed with brine and dried over sodium sulfate and concentrated. The crude and potassium carbonate (1.1 g) was added to MeOH (20 mL). The reaction mixture was stirred for 2 h. AcOH (1.0 mL) was added and MeOH was removed. The residue was purified by preparative HPLC to give 70 mg of 2-(4-hydroxyphenyl)-4-oxo-4H-chromene-6-carbonitrile. MS (ES) m/z: 264.91 (M+1), 263.90 (M); Mp. 296-298° C.

1. extractionextracted with dichloromethane (150 mL)
2. washThe organic layer was washed with sodium bicarbonate, brine
3. dry with materialdried over sodium sulfate
4. concentrationfollowed by concentration
5. customThe crude compound (1.40 g, 89.5%) was obtained
6. customafter evaporation of the solvent
7. additionwas added
8. stirringthe reaction mixture was stirred at rt for 2 h
9. customThe solvent was removed
10. additionfollowed by addition of water (50 mL) and EtOAc (150 mL)
11. extractionto extract out the compound
12. washThe organic layer was washed with brine
13. dry with materialdried over sodium sulfate
14. additionThe crude product (1.20 g) and 4 drops of sulfuric acid were added to AcOH (15 mL)
15. temperatureThe reaction mixture was heated to 110° C. for 1 h
16. customAcOH was removed
17. additionsodium bicarbonate solution was added
18. extractionfollowed by extraction with EtOAc
19. washThe organic layer was washed with brine
20. dry with materialdried over sodium sulfate
21. concentrationconcentrated
22. additionThe crude and potassium carbonate (1.1 g) was added to MeOH (20 mL)
23. stirringThe reaction mixture was stirred for 2 h
24. additionAcOH (1.0 mL) was added
25. customMeOH was removed
26. customThe residue was purified by preparative HPLC