反应详情

A mixture of 15 g 3-amino-5-mercapto-s-triazole, 28 g diethyl ethoxymethylenemalonate and 70 ml acetic acid was refluxed for 18 hours. After removing the solvent by distillation, the remaining brown oil was allowed to cool to room temperature, and the pH was adjusted to 10 with sodium hydroxide solution. After washing with 100 ml ethyl acetate, the brown aqueous solution was neutralized to pH 7.5 with 6N hydrochloric acid, and again washed with 100 ml ethyl acetate. The pH of the aqueous layer was lowered to 3.0 with 6N hydrochloric acid, and the separated crude product (12 g) was collected by filtration and recrystallized from 30 ml methanol, giving 9 g of the objective compound as colorless crystals.

1. temperaturewas refluxed for 18 hours
2. customAfter removing the solvent
3. distillationby distillation
4. washAfter washing with 100 ml ethyl acetate
5. washagain washed with 100 ml ethyl acetate
6. customthe separated crude product (12 g)
7. filtrationwas collected by filtration
8. customrecrystallized from 30 ml methanol