反应详情

To a solution of 127.5 g (1.5 mol) cyanoacetic acid and 200 ml of acetic anhydride was added 120 g (1.36 mol) of ethylurea. The solution was stirred at 60°-70° C. for 2 hours. After cooling, white crystals were filtered off and washed with ethanol. Yield 153 g (74%) (I). This was stirred in 1 liter of hot water and 160 ml of 2 N NaOH was added in portions so the solution the whole time was basic. The reaction mixture was refluxed for 20 minutes and then neutralized with 5 N HCl. After cooling, white crystals were filtered off. Yield 100 g (65%) (II) NMR.

1. temperatureAfter cooling
2. filtrationwhite crystals were filtered off
3. washwashed with ethanol
4. stirringThis was stirred in 1 liter of hot water
5. addition160 ml of 2 N NaOH was added in portions so the solution the whole time
6. temperatureThe reaction mixture was refluxed for 20 minutes
7. temperatureAfter cooling
8. filtrationwhite crystals were filtered off