反应详情

A cold solution of benzenediazonium chloride [prepared, by the method well known in the art, from 13.3 g. aniline in a 1:1 v/v mixture of water and concentrated hydrochloric acid (120 ml)] was added dropwise with stirring to a solution of 4-amino-2-isopropylpyrimid-6-one (28 g.) and sodium hydroxide (14.8 g.) in water (450 ml.) at 5° C. After stirring for a further 1 hour, the mixture was filtered. The filtrate was adjusted to pH 6 by the addition of aqueous sodium hydroxide solution, and the resultant solid was isolated to give crude 4-amino-2-isopropyl-5-phenylazopyrimid-6-one (33.5 g.), m.p. 215°-219° C. Recrystallisation from ethanol gave pure 4-amino-2-isopropyl-5-phenylazopyrimid-6-one (8.3 g.), m.p. 235°-236° C. (with decomposition).

1. additionwas added dropwise
2. filtrationthe mixture was filtered
3. additionThe filtrate was adjusted to pH 6 by the addition of aqueous sodium hydroxide solution
4. customthe resultant solid was isolated
5. customto give crude 4-amino-2-isopropyl-5-phenylazopyrimid-6-one (33.5 g.), m.p. 215°-219° C
6. customRecrystallisation from ethanol