反应详情

温度

90 °C

250 parts of water, 98 parts of N-methylcyanoacetamide and 169 parts of acetoacetic acid ethyl ester are initially placed in an autoclave, 40 parts of gaseous monomethylamine are injected, while stirring, and the reaction mixture is then heated at 90° C. for 3 hours, a pressure of 2.9 bars being generated. The batch is diluted with 400 parts of water, 80 parts of 61% strength sulphuric acid are added at 30°-35° C., the batch is cooled to 20° C. and the precipitate which has been formed is filtered off. 155.8 parts (95% of theory) of 1,4-dimethyl-3-cyano-6-hydroxypyrid-2-one with a melting point of 285° C. are obtained.

1. additionare added at 30°-35° C.
2. temperaturethe batch is cooled to 20° C.
3. customthe precipitate which has been formed
4. filtrationis filtered off