反应详情

To a solution of {[2,6-difluoro-4-(5-methyl-3-phenyl-isoxazol-4-yl)phenyl]thio}methyl acetate in methanol (30 mL) and dichloromethane (70 mL) was added magnesium monoperoxyphthalate hexahydrate (8.6 g 80%, 14 mmol). The slurry was heated and held at reflux for 4 hours, then poured into water and extracted with dichloromethane (1×150 mL, 3×75 mL). The combined extracts were washed with dilute sodium chloride twice, dried with magnesium sulfate, and concentrated. The residue was dissolved in dichloromethane (40 mL) and methanol (20 mL), magnesium monoperoxyphthalate hexahydrate (4.5 g, 7.3 mmol) was added, and the mixture heated and held at reflux for 5 hours. Additional magnesium monoperoxyphthalate hexahydrate was added and the mixture heated and held at reflux for 18 hours. The reaction mixture was poured into dilute ammonium chloride and extracted with dichloromethane (1×200 mL, 2×50 mL). The combined extracts were washed twice with dilute ammonium chloride, dried with magnesium sulfate, and concentrated. Purification by silica gel chromatography using 30% ethyl acetate in hexanes gave white solids, which were dissolved in dichloromethane, washed with dilute sodium bicarbonate, dried with magnesium sulfate, and concentrated to provide {[2,6-difluoro-4-(5-methyl-3-phenylisoxazol-4-yl)phenyl]sulfonyl}methyl acetate as a white solid (1.4 g, 54%). Recrystallization from ethyl acetate/hexanes gave an analytical sample of the product, MP 164.6-165.6° C. 1H NMR (CDCl3/400 MHz) 7.35-7.46 (m, 5H), 6.82-6.86 (m, 2H), 5.33 (s, 2H), 2.54 (s, 3H) 2.12 (s, 3H). HRMS m/z 408.0725 (M+H+, calcd 408.0717). Anal. Calcd for C19H15F2NO5S: C, 56.02; H, 3.71; N, 3.44; Found: C, 56.07; H, 3.61, N, 3.58.

1. temperatureThe slurry was heated
2. temperatureat reflux for 4 hours
3. extractionextracted with dichloromethane (1×150 mL, 3×75 mL)
4. washThe combined extracts were washed with dilute sodium chloride twice
5. dry with materialdried with magnesium sulfate
6. concentrationconcentrated
7. dissolutionThe residue was dissolved in dichloromethane (40 mL)
8. temperaturethe mixture heated
9. temperatureat reflux for 5 hours
10. temperaturethe mixture heated
11. temperatureat reflux for 18 hours
12. extractionextracted with dichloromethane (1×200 mL, 2×50 mL)
13. washThe combined extracts were washed twice with dilute ammonium chloride
14. dry with materialdried with magnesium sulfate
15. concentrationconcentrated
16. customPurification by silica gel chromatography
17. customgave white solids, which
18. washwashed with dilute sodium bicarbonate
19. dry with materialdried with magnesium sulfate
20. concentrationconcentrated