3-Methoxypyridine

(1) Place the raw material 3-halopyridine, hydrogen peroxide, and acetic acid in a molar ratio of 10:3:4 into a 500mL three-necked flask and react at 40-80℃ for 4-8h under stirring. Recover the acetic acid, add saturated sodium carbonate solution and stir to make the system alkaline. After evaporating the water, add chloroform to wash, filter off the salt, recover the chloroform, and vacuum distill to obtain N-oxide-3-halopyridine;

(2) Add the N-oxide-3-halopyridine and alkoxy salt obtained in (1) in a molar ratio of 1:1.2 into a 500mL three-necked flask.

In a three-necked flask, catalyst A and alcohol were added, and the mixture was refluxed for 5-8 hours with stirring. After cooling, the mixture was neutralized to neutral, the alcohol was recovered, water was evaporated, and N-oxy-3-alkoxypyridine was obtained by distillation. (3) The N-oxy-3-alkoxypyridine obtained in (2), ferric chloride, and hydrazine hydrate were added to a 500 mL three-necked flask in a molar ratio of 20:3:40. Activated carbon and ethanol were then added, and the mixture was reacted at 70 °C for 3 hours. After cooling to room temperature, the activated carbon was filtered off, the alcohol was evaporated, and 3-methoxypyridine was obtained by vacuum distillation.