[C:1]([NH:9][C:10]([N:12]1[C:16]2([C:30]3[CH:35]=[C:34]([Br:36])[CH:33]=[CH:32][C:31]=3[F:37])[CH2:17][N:18]([C:20]([O:22][CH2:23][C:24]3[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=3)=[O:21])[CH2:19][CH:15]2[CH2:14][O:13]1)=[S:11])(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1>C(O)(=O)C.C(OCC)(=O)C.[Zn]>[C:1]([NH:9][C:10]([NH:12][C:16]1([C:30]2[CH:35]=[C:34]([Br:36])[CH:33]=[CH:32][C:31]=2[F:37])[CH:15]([CH2:14][OH:13])[CH2:19][N:18]([C:20]([O:22][CH2:23][C:24]2[CH:25]=[CH:26][CH:27]=[CH:28][CH:29]=2)=[O:21])[CH2:17]1)=[S:11])(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1A mixture of benzyl 1-(benzoylcarbamothioyl)-6a-(5-bromo-2-fluoro-phenyl)-3,3a,4,6-tetrahydropyrrolo[3,4-c]isoxazole-5-carboxylate (6.05 g 10.4 mmol) and zinc (dust, <10 micron) (6.77 g, 103.5 mmol) is stirred in acetic acid (52 mL) at room temperature overnight under nitrogen. The reaction is diluted with ethyl acetate and filtered through diatomaceous earth. The solvent is removed in vacuo and the residue is diluted with ethyl acetate, water and saturated aqueous sodium bicarbonate. The mixture is extracted with ethyl acetate (3×), the combined organic layers are combined and dried over sodium sulfate, filtered and the solvent removed in vacuo. The crude product is purified over silica gel with a 30 minute 5% to 100% EtOAc in hexanes gradient to give the title compound (5.222 g, 86%). ES/MS (m/e): (79Br/81Br) 586/588 (M+H).
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