F[C:2]1[C:7]([F:8])=[CH:6][CH:5]=[C:4]([F:9])[N:3]=1.[CH3:10][O-:11].[Na+]>CO.[Cl-].[Na+].O>[F:8][C:7]1[C:2]([O:11][CH3:10])=[N:3][C:4]([F:9])=[CH:5][CH:6]=12,3,6-Trifluoropyridine (17.91 ml, 188 mmol) was dissolved in anhydrous MeOH (300 ml) and the resulting mixture was placed under argon. This mixture then was treated with a 25 wt % methanolic solution of sodium methoxide (43.0 ml, 188 mmol). The resulting mixture was then heated at about 65° C. for 2 hr. The reaction mixture was cooled to ambient temperature, and concentrated in vacuo to yield a residue which then was mixed with brine (200 mL), and extracted with Et2O (3×200 ml). The combined extracts were dried (Na2SO4), filtered, and concentrated in vacuo to give 21.5 g (79% yield) of crude 3,6-difluoro-2-methoxypyridine as a white solid which was carried on to the next step without purification.
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