[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].C1CCC(N=C=NC2CCCCC2)CC1>CN(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]A mixture of α-trifluoromethylacrylic acid (700 mg; 5.0 mmoles) and 1,3-dimethylurea (419 mg; 4.8 mmoles) in DMF (5 ml) was cooled to 0° C., and then a solution of DCC (1.21 g; 5.9 mmoles) in DMF (3 ml) was added dropwise. The mixture was stirred at 0° C. for 1 hour. The precipitated solid was filtered off, and washed with ethyl acetate. The solvents were evaporated under reduced pressure from the combined filtrates. The residue was purified by a column chromatography on silica gel to give 566 mg (yield 57%) of 1,3-dimethyl-5-trifluoromethyl-5,6-dihydrouracil (OF-1).
Loading…
