反应详情

A mixture of diethyl 2-ethoxy-3-oxo-succinate (55.86 g, 1 eq) and urea (14.41 g, 1 eq.) was refluxed for 2.5 h in 1 M HCl—AcOH (1200 ml, 5 eq.) and allowed to become cool. The cooled mixture was evaporated to dryness. The residues were dissolved in MeOH, heated aside for crystallization. After crystallization, the precipitates were filtered to give a product which was an off-white solid (15.11 g, 27.5%).

1. temperatureto become cool
2. customThe cooled mixture was evaporated to dryness
3. dissolutionThe residues were dissolved in MeOH
4. temperatureheated aside for crystallization
5. customAfter crystallization
6. filtrationthe precipitates were filtered
7. customto give a product which