18677-48-0

124-41-4

71902-33-5

18677-48-0

1. 3,5-difluoropyridine (5.4 g, 46.8 mmol, 1 eq.) was dissolved in methanol (45 mL). 2. Sodium methanolate (7.5 g, 140.4 mmol) was added to the above solution. 3. The reaction mixture was divided equally into three microwave reactor tubes. 4. Heat each tube separately in the microwave reactor at 135 °C for 1 hour. 5. 5. Upon completion of the reaction, the contents of the three reaction tubes were combined and concentrated. 6. The concentrate was diluted with a mixture of ethyl acetate (100 mL) and brine (30 mL). 7. The organic layer was separated, dried over anhydrous sodium sulfate, and concentrated. 8. Redissolve the crude product in methanol (45 mL) and add sodium methanolate (7.5 g, 140.4 mmol). 9. Steps 3 through 7 were repeated. 10. Dissolve the final crude product in a mixture of ethyl acetate (200 mL) and brine (30 mL). 11. Separate the organic layer, dry with anhydrous sodium sulfate, and concentrate. 12. The product was purified by silica gel column chromatography using a mixture of ethyl acetate and hexane as eluent to afford 3,5-dimethoxypyridine (3.73 g, 57% yield) as an off-white solid. 13. The product was confirmed by 1H NMR (400 MHz, CDCl3): δ 7.98 (d, J=2.4 Hz, 2H), 6.76 (t, J=2.4 Hz, 1H), 3.88 (s, 6H). 14. lRMS (M+H+) m/z 140.1.