[C:1]1([C:7]2[C:11]([C:12]([F:15])([F:14])[F:13])=[C:10]([CH2:16][OH:17])[O:9][N:8]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.CC(OI1(OC(C)=O)(OC(C)=O)OC(=O)C2C=CC=CC1=2)=O.C([O-])(O)=O.[Na+].S([O-])([O-])(=O)=S.[Na+].[Na+]>ClCCl.CC(OI1(OC(C)=O)(OC(C)=O)OC(=O)C2C=CC=CC1=2)=O>[C:1]1([C:7]2[C:11]([C:12]([F:15])([F:13])[F:14])=[C:10]([CH:16]=[O:17])[O:9][N:8]=2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1
To (3-phenyl-4-(trifluoromethyl)isoxazol-5-yl)methanol (Intermediate I-12A, 0.4 g, 1.645 mmol) in dichloromethane (5 mL) was added Dess-Martin Periodinane (0.767 g, 1.809 mmol) over a period of 2 min. at 0° C. under a nitrogen atmosphere. The milky suspension was stirred at 0° C. for 10 min. and at room temperature for 30 min. An additional 65 mgs of Dess-Martin reagent was added at room temperature and the contents were stirred at room temperature for 3 h. To the reaction mixture was added 10 mL of a 1:1 mixture of sat. aq. NaHCO3 and aq. sodium thiosulfate, slowly at room temperature. After stirring the reaction mixture for 10 min. at room temperature, the dichloromethane layer was separated and the aqueous layer re-extracted with dichloromethane (10 mL). The combined dichloromethane layers were dried over sodium sulfate and concentrated under reduced pressure to yield 3-phenyl-4-(trifluoromethyl)isoxazole-5-carbaldehyde (0.385 g, 1.596 mmol, 97% yield) as an oil, which was used as such for the subsequent step without further purification. 1H NMR (400 MHz, CDCl3) δ ppm 10.14 (s, 1H) 7.63-7.70 (m, 2H) 7.47-7.60 (m, 3H).
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