[Br:1][C:2]1[C:3]([S:18][CH2:19][C:20]([OH:22])=[O:21])=[CH:4][C:5]2[O:9][N:8]=[C:7]([C:10]3[CH:15]=[CH:14][CH:13]=[CH:12][C:11]=3[F:16])[C:6]=2[CH:17]=1.I([O-])(=O)(=O)=[O:24].[Na+].I([O-])(=O)=O.[Na+]>CO.O>[Br:1][C:2]1[C:3]([S:18]([CH2:19][C:20]([OH:22])=[O:21])=[O:24])=[CH:4][C:5]2[O:9][N:8]=[C:7]([C:10]3[CH:15]=[CH:14][CH:13]=[CH:12][C:11]=3[F:16])[C:6]=2[CH:17]=12.8 g (7.33 mmol) of [[5-bromo-3-(2-fluorophenyl)-1,2-benzisoxazol-6-yl]thio]acetic acid was combined with 30 ml (2 eq.) of 0.5M sodium periodate solution in 300 ml of 4:1 methanol/water. The mixture was refluxed for 18 hours during which the insoluble sodium iodate precipitated. The reaction mixture was then poured into excess 3N HCl and extracted several times with ethyl acetate. The ethyl acetate extracts were combined, washed with water and a saturated salt solution, dried over magnesium sulfate, filtered and evaporated to yield a white solid. The solid was triturated with hexanes and dried under vacuum to yield 2.51 g (86%) of [[5-bromo-3-(2-fluorophenyl)-1,2-benzisoxazol-6-yl]sulfinyl]acetic acid, m.p. 173°-174° C.
Wird geladen…