反应详情

To 20 mL of stirring chlorosulfonic acid cooled to −5° C. was added 3,4-diphenyl-2-(5H )-furanone (Step 1)(3.160 g, 13.4 mmol) portion-wise over 30 minutes. The solution was warmed to room temperature and maintained at that temperature for 16 hours. The reaction mixture was diluted with dichloromethane and quenched into ice water. The phases were separated and the aqueous phase extracted with dichloromethane, the combined dichloromethane extract was dried over anhydrous MgSO4, filtered and concentrated in vacuo. The residue was diluted with dichloromethane and added to excess concentrated NH4OH. The mixture was stirred for 1 hour. The phases were separated and the aqueous phase was extracted with dichloromethane. The organic extract was dried over anhydrous MgSO4, filtered and concentrated in vacuo to give a white solid that was crystallized from aqueous ethanol to afford pure 3-[(4-aminosulfonyl)phenyl)]-4-phenyl-2-(5H )-furanone (2.110 g, 50%): mp 225.5-226.5° C. 1H NMR (CDCl3/300 MHz) 7.79 (d, 2H, J=8.4 Hz), 7.41 (d, 2H, J=8.4 Hz), 6.38 (brs, 2H), 5.09 (s, 2H). FABLRMS m/z 316 (m+H). Anal. Calc'd for C16H13NO4S: C, 60.94; H, 4.16; N, 4.44. Found: C, 60.86; H, 4.18; N, 4.40.

1. temperaturemaintained at that temperature for 16 hours
2. customquenched into ice water
3. customThe phases were separated
4. extractionthe aqueous phase extracted with dichloromethane
5. extractionthe combined dichloromethane extract
6. dry with materialwas dried over anhydrous MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. additionThe residue was diluted with dichloromethane
10. additionadded to excess concentrated NH4OH
11. customThe phases were separated
12. extractionthe aqueous phase was extracted with dichloromethane
13. extractionThe organic extract
14. dry with materialwas dried over anhydrous MgSO4
15. filtrationfiltered
16. concentrationconcentrated in vacuo
17. customto give a white solid
18. customthat was crystallized from aqueous ethanol