反应详情

12.5 g of 1-ethyl-3-methyl-5-aminopyrazole (0.1 mol) and 21.6 g of ethoxymethylene malonic acid diethyl ester (0.1 mol) are heated to 120° (bath temperature) for 2 hours with stirring. The ethanol formed by this reaction is removed by means of a water aspirator. Vacuum distillation (b.p. 0.05 152°-153°) yields 24.0 g (81.5% of theory) of a quickly crystallizing oil, [[(1-ethyl-3-methyl-5-pyrazolyl)-amino]methylene]malonic acid diethyl ester, m.p. 60°-67°. The product, recrystallized from ligroin (90°-100°), melts at 69°-70°.

1. customis removed by means of a water aspirator
2. distillationVacuum distillation (b.p. 0.05 152°-153°)
3. customyields 24.0 g (81.5% of theory) of
4. customa quickly crystallizing oil, [[(1-ethyl-3-methyl-5-pyrazolyl)-amino]methylene]malonic acid diethyl ester, m.p. 60°-67°
5. customThe product, recrystallized from ligroin (90°-100°), melts at 69°-70°