Dicyclohexylcarbodiimide → 3-Methyl-5-(trifluoromethyl)dihydropyrimidine-2,4(1H,3H)-dione
Reaction equation
[F:1][C:2]([F:9])([F:8])[C:3](=[CH2:7])[C:4](O)=[O:5].[CH3:10][NH:11][C:12]([NH2:14])=[O:13].C1(N=C=NC2CCCCC2)CCCCC1>CN(C=O)C>[CH3:10][N:11]1[C:4](=[O:5])[CH:3]([C:2]([F:9])([F:8])[F:1])[CH2:7][NH:14][C:12]1=[O:13].[CH3:10][N:11]1[CH2:7][CH:3]([C:2]([F:9])([F:8])[F:1])[C:4](=[O:5])[NH:14][C:12]1=[O:13]Participants
6
Reactant 3
Product 2
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 80 °C
Procedure
A mixture of α-trifluoromethylacrylic acid (700 mg; 5.0 mmoles) and methylurea (370 mg; 5.0 mmoles) in DMF (5 ml) was heated at 80° C. with stirring for 3 hours. After cooling to 0° C., a solution of dicyclohexylcarbodiimide (DCC) (1.05 g; 5.1 mmoles) in 3 ml of DMF was added dropwise. The mixture was stirred for 1 hour, and the precipitated solid was filtered off and washed with ethyl acetate. The solvent was evaporated under reduced pressure from the combined filtrates. The residue was purified by a column chromatography on silica gel (ethyl acetate:chloroform=1:3) to give 424 mg (yield: 43%) of 3-methyl-5-trifluoromethyl-5,6-dihydrouracil (OF-2) and 174 mg (yield: 18%) of 1-methyl-5-trifluoromethyl-5,6-dihydrouracil (OF-3).
Workup
- temperatureAfter cooling to 0° C.
- stirringThe mixture was stirred for 1 hour
- filtrationthe precipitated solid was filtered off
- washwashed with ethyl acetate
- customThe solvent was evaporated under reduced pressure from the combined filtrates
- customThe residue was purified by a column chromatography on silica gel (ethyl acetate:chloroform=1:3)
Sources & evidence
- ORD record
- ord-1603c044245149dd8d72c576887484f6
- Source dataset
- uspto-grants-1986_04
- Patent number
- US04581452
Reaction notes
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