反应详情

温度

0 °C

Ethyl butyrimidate hydrochloride from Example B (71.5 g, 472 mmol) is introduced into triethylamine (65 ml, 472 mmol) and cooled to 0° C. 2-Ethoxybenzohydrazide from Example A (85 g, 472 mmol) is suspended in 250 ml of isopropanol and added to the ethyl butyrimidate mixture. The reaction mixture is stirred at room temperature for 48 hours, the solid (triethylamine hydrochloride) is removed, and 25% strength hydrochloric acid (150 ml, 1.18 mol) is slowly added dropwise to the mother liquor at 0° C. to 5° C. The suspension of crystals is then stirred at 0° C. to 5° C. for 1 hour and the crystals are filtered with suction through a sintered funnel, washed with 100 ml of cold isopropanol and dried in a vacuum oven at 30° C. and 300 mbar overnight.

1. customthe solid (triethylamine hydrochloride) is removed
2. additionThe suspension of crystals
3. stirringis then stirred at 0° C. to 5° C. for 1 hour
4. filtrationthe crystals are filtered with suction through a sintered funnel
5. washwashed with 100 ml of cold isopropanol
6. customdried in a vacuum oven at 30° C.
7. custom300 mbar overnight