[Cl:1][C:2]1[CH:3]=[C:4]([C@@:10]2([C:29]([F:32])([F:31])[F:30])[O:14][N:13]=[C:12]([C:15]3[CH:27]=[CH:26][C:18]([C:19]([O:21]C(C)(C)C)=[O:20])=[C:17]([CH3:28])[CH:16]=3)[CH2:11]2)[CH:5]=[C:6]([Cl:9])[C:7]=1[F:8].FC(F)(F)C(O)=O>C(Cl)Cl>[Cl:1][C:2]1[CH:3]=[C:4]([C@@:10]2([C:29]([F:31])([F:32])[F:30])[O:14][N:13]=[C:12]([C:15]3[CH:27]=[CH:26][C:18]([C:19]([OH:21])=[O:20])=[C:17]([CH3:28])[CH:16]=3)[CH2:11]2)[CH:5]=[C:6]([Cl:9])[C:7]=1[F:8]A 100 mL vessel was charged with tert-butyl 4-[(5S)-5-(3,5-dichloro-4-fluoro-phenyl)-5-(trifluoromethyl)-4H-isoxazol-3-yl]-2-methyl-benzoate (3.1 g, 6.3 mmol) and dissolved in CH2Cl2 (30 mL) and then cooled down to 0° C. To this mixture 2,2,2-trifluoroacetic acid (4.3 g, 38 mmol) was added over 10 min. After addition the reaction was brought to room temperature and the mixture stirred over night after which time LC-MS analysis showed a complete conversion. The crude mixture was concentrated and the residue dissolved in 300 mL of ethylacetate, washed with brine, dried over MgSO4 and evaporated to yield 2.7 g of the crude title product which was directly used for the step D.
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