反应详情

46.1 g of crude methyl 1-ethyl-6-methyl-2-(4'-chlorophenyl)-4-oxonicotinate is suspended in 600 ml of 5% aqueous NaOH solution and warmed to 80°-85°. After 11/2 hours at this temperature the reaction mixture is cooled and acidified with dilute HCl. The resulting solid precipitate is collected by filtration, yielding 42 g of 1-ethyl-6-methyl-2-(4'-chlorophenyl)-4-oxonicotinic acid, mp (methylene choride/ether)=235°-237° C.

1. temperaturewarmed to 80°-85°
2. temperatureAfter 11/2 hours at this temperature the reaction mixture is cooled
3. filtrationThe resulting solid precipitate is collected by filtration