反应详情

A solution of 15.8 g (0.1 mol) of N,N-dimethyl-2-(hydroxyimino)-3-oxobutanamide in 400 ml of ethanol and 100 ml of 2N hydrochloric acid over 2 g of catalyst (5% palladium on charcoal) is hydrogenated in a Paar shaker until 1 molar equivalent of hydrogen is taken up (3-5 hours). The catalyst is removed by filtration. A solution of 16.2 g (0.2 mol) of potassium cyanate in 80 ml of water is added, the solution is refluxed for 1 hour and concentrated until the product crystallizes. Recrystallization from 50% aqueous ethanol gives the title compound, m.p. 244°-246° C. (dec).

1. custom(3-5 hours)
2. customThe catalyst is removed by filtration
3. temperaturethe solution is refluxed for 1 hour
4. concentrationconcentrated until the product
5. customcrystallizes
6. customRecrystallization from 50% aqueous ethanol