[F:1][C:2]1[CH:9]=[C:8]([B:10]2[O:14]C(C)(C)C(C)(C)[O:11]2)[CH:7]=[C:6]([F:19])[C:3]=1[C:4]#[N:5]>CC(C)=O.O>[C:4]([C:3]1[C:2]([F:1])=[CH:9][C:8]([B:10]([OH:14])[OH:11])=[CH:7][C:6]=1[F:19])#[N:5]2,6-Difluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzonitrile (55 g) was dissolved in acetone (1 L) and water (1 L). T this stirred mixture was added NaIO4 (160 g) and NH4OAc (50 g). The reaction mixture was stirred at room temperature overnight and then filtered. The filtrate was evaporated under vacuum at 40° C. until most of acetone was removed. The residue was cooled to 0° C. and 2N NaOH (1 L) solution was added with stirring over 30 minutes. The mixture was filtered, and the filtrate was washed with CH2Cl2 (1 L). To the aqueous layer was added 5N hydrochloric acid at 0° C. until pH=2. The resulting solid was filtered and then dissolved in EtOAc (1.5 L), dried over Na2SO4, filtered and evaporated under vacuum to provide 30 g of the title compound as a white solid.
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