反应详情

1.5 g. (13.6 mmole) 3-methyl-1H-pyrazole-5-aldehyde was stirred with 4.5 g. sodium hydrogen sulphite in 9 ml. water for 3 hours at 60° C. The evaporation residue was stirred with 2.79 g. (13.6 mmole) 4,4-dimethyl-6,7-diamino-1,2,3,4-tetrahydroquinolin-2-one and 40 ml. ethanol for 3 hours at 60° C. while passing through air. Half of the ethanol was distilled off, water was added and the residue was filtered off with suction and recrystallized from ethyl acetate/methanol to give 3.3 g. (82.5% of theory) of the title compound; m.p. 242°-245° C.

1. distillationHalf of the ethanol was distilled off
2. additionwater was added
3. filtrationthe residue was filtered off with suction
4. customrecrystallized from ethyl acetate/methanol
5. customto give 3.3 g