反应详情

A stirred solution of sodium methoxide in dry methanol [prepared from sodium (10.7 g.) and dry methanol (150 ml.)] maintained at 0° C. was treated with 2-methoxybenzamidine hydrochloride (21.6 g.) followed by ethyl α-oximinocyanoacetate (16.5 g.). The mixture was then heated to reflux with stirring for 4.5 hours, and then poured into water (1000 ml.) and brought to pH6 by the addition of glacial acetic acid. The resultant green solid was filtered off and recrystallised from aqueous acetic acid to give 4-amino-2-(2-methoxyphenyl)-5-nitrosopyrimid-6-one (19.2 g.), m.p. 210°-211° C. (with decomposition). A further quantity of less pure 4-amino-2-(2-methoxyphenyl)-5-nitrosopyrimid-6-one (2.9 g.) was obtained by concentration of the mother liquors of the recrystallisation.

1. temperatureThe mixture was then heated
2. temperatureto reflux
3. filtrationThe resultant green solid was filtered off
4. customrecrystallised from aqueous acetic acid