反应详情

130.5 g of 2-butylamino-5-cyano-6-methyl-3-pyridine-carboxylic acid, ethyl ester (0.5 mol) are dissolved in 400 ml of diethyleneglycoldimethyl ether. 61.1 g of selenium dioxide are added and the mistrue is heated at reflux temperature for 1 hour. The mixture is filtered hot and evaporated to dryness. The resulting yellow oil of 2-butylamino-5-cyano-6-formyl-3-pyridine-carboxylic acid, ethyl ester is crystallized with diethyl ether. Yield 95 g (69%); m.p. 81°-83° C. (methanol).

1. temperaturethe mistrue is heated
2. temperatureat reflux temperature for 1 hour
3. filtrationThe mixture is filtered hot
4. customevaporated to dryness
5. customThe resulting yellow oil of 2-butylamino-5-cyano-6-formyl-3-pyridine-carboxylic acid, ethyl ester is crystallized with diethyl ether