N,N'-Dimethylurea → 1,3-Dimethyl-5-(trifluoromethyl)dihydropyrimidine-2,4(1H,3H)-dione
Reaktionsgleichung
[F:1][C:2]([F:9])([F:8])[C:3](=[CH2:7])[C:4](O)=[O:5].[CH3:10][NH:11][C:12]([NH:14][CH3:15])=[O:13].C(OC(=O)C)(=O)C>>[CH3:10][N:11]1[CH2:7][CH:3]([C:2]([F:9])([F:8])[F:1])[C:4](=[O:5])[N:14]([CH3:15])[C:12]1=[O:13]Komponenten
4
Reaktionsbedingungen
- Temperatur
- 100 °C
Versuchsvorschrift
A mixture of α-trifluoromethylacrylic acid (4.31 g; 30.8 mmoles), 1,3-dimethylurea (2.75 g; 31.2 mmoles) and acetic anhydride (17 ml) was heated at 100° C. with stirring for one hour. The solvent was evaporated under reduced pressure, and the residue was purified by a column chromatography on silica gel (CHCl3) to give 5.50 g (yield: 84%) of 1,3-dimethyl-5-trifluoromethyldihydrouracil.