Ethanol → 5,6-Diamino-2-(ethoxymethyl)-4(3H)-pyrimidinone hemimaleate

Reaction equation

[NH2:1][C:2]1[C:3](=[O:13])[NH:4][C:5]([CH2:9][O:10][CH2:11][CH3:12])=[N:6][C:7]=1[NH2:8].[C:14]([OH:21])(=[O:20])/[CH:15]=[CH:16]\[C:17]([OH:19])=[O:18].C(O)C>CO>[C:14]([OH:21])(=[O:20])/[CH:15]=[CH:16]\[C:17]([OH:19])=[O:18].[NH2:1][C:2]1[C:3](=[O:13])[NH:4][C:5]([CH2:9][O:10][CH2:11][CH3:12])=[N:6][C:7]=1[NH2:8].[NH2:1][C:2]1[C:3](=[O:13])[NH:4][C:5]([CH2:9][O:10][CH2:11][CH3:12])=[N:6][C:7]=1[NH2:8]

Participants

Procedure

A mixture of 3.4 g (0.0185 mole) of 5,6-diamino-2-(ethoxymethyl)-4(3H)-pyrimidinone, 4.4 g (0.0379 mole) of maleic acid, 300 ml of absolute ethanol and 100 ml of methanol is brought to reflux. The small insoluble portion is removed by filtration while hot. After cooling, the precipitate formed is isolated by filtration; it is washed with ethyl ether and recrystallized from absolute ethanol. Yld: 2.0 g (45%), m.p. 192°-194° C.