反应详情

21.7 g of 2,3,4,5-tetrahydro-3-oxo-4-[(pyridin-3-yl)-methyleneamino]-6-methyl-1,2,4-triazine are dissolved, with heating, in 60 ml of 2N hydrochloride acid. The hot solution is filtered and cooled. The precipitate which crystallises out is isolated by filtration, washed with alcohol and ether and dried in vacuo to give the title compound of formula ##STR32## in the form of a colourless crystal powder; m.p. 240°-241° C. with decomposition; yield: 19 g (75 %).

1. filtrationThe hot solution is filtered
2. temperaturecooled
3. customThe precipitate which crystallises out
4. customis isolated by filtration
5. washwashed with alcohol and ether
6. customdried in vacuo