[Cl:1][C:2]1[C:3]([F:21])=[N:4][C:5]([F:20])=[C:6]([Cl:19])[C:7]=1[CH2:8][C:9]([O:11]CC1C=CC=CC=1)=[O:10]>[Pd].C(O)C>[Cl:19][C:6]1[C:5]([F:20])=[N:4][C:3]([F:21])=[C:2]([Cl:1])[C:7]=1[CH2:8][C:9]([OH:11])=[O:10]Benzyl 2-(3,5-dichloro-2,6-difluoropyridin-4-yl)acetate (30.9 g, 93 mmol), anhydrous ethanol, and 10% palladium on carbon were placed into a 500 mL bottle. The mixture was then hydrogenated using Parr Hydrogenator under hydrogen atmosphere (20 psi) for 30 min. The reaction mixture was then filtered through celite pad and the pad was washed with ethanol. The filtrate was evaporated in vacuo and the residue was recrystallized from MC to afford 21 g (89%) of 2-(3,5-dichloro-2,6-difluoropyridin-4-yl)acetic acid as a white solid. m.p. 157-159° C. 1H NMR (200 MHz, CDCl3) δ 4.13 (2H, s).
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