反应详情

A mixture of piperazine (86 g, 1.0 mol), 1-(2-chloroethyl)-imidazolidin-2-one (74 g, 0.5 mol) and sodium carbonate (159 g, 1.5 mol) in ethanol (500 ml) was refluxed with stirring for 1.5 hours. A solution of 1-(2-chloroethyl)-imidazolidin-2-one (74 g, 0.5 mol) in methanol (75 ml) was then added in the course of 1.5 hours, at reflux temperature, whereupon the reaction mixture was refluxed for 18 hours. After cooling, the reaction mixture was filtered and evaporated in vacuo. The residue was dissolved in hot ethanol (100 ml), whereupon ethyl acetate (200 ml) was added. The crystals were filtered and dried to give 1-(2-(2-imidazolidinon-1-yl)ethyl)piperazine (60 g) mp. 136°-140° C. Additional 22 g could be obtained from the mother liquor.

1. temperaturewas refluxed
2. temperatureat reflux temperature
3. temperaturewhereupon the reaction mixture was refluxed for 18 hours
4. temperatureAfter cooling
5. filtrationthe reaction mixture was filtered
6. customevaporated in vacuo
7. dissolutionThe residue was dissolved in hot ethanol (100 ml)
8. additionwhereupon ethyl acetate (200 ml) was added
9. filtrationThe crystals were filtered
10. customdried