3-Pyridinecarboxaldehyde → 4,5-Dihydro-6-methyl-4-((3-pyridinylmethylene)amino)-1,2,4-triazin-3(2H)-one

Participants

Reaction Steps

26.8 g (0.25 mole) of pyridine-3-carbaldehyde and 1 drop of concentrated HCl are added at 60° C. to 32 g (0.25 mole) of 2,3,4,5-tetrahydro-3-oxo-4-amino-6-methyl-1,2,4-triazine dissolved in 250 ml of ethanol. After boiling for half an hour under reflux, the reaction mixture is cooled and the solid portion is isolated by filtration, washed with ether and dried to give the title compound of formula ##STR22## in the form of a colourless solid; m.p. 227°-228° C.; yield: 48 g (90 %).

Provenance & Evidence