[H-].[Na+].[O:3]=[C:4]1[NH:9][CH:8]=[N:7][CH:6]=[C:5]1[C:10]([O:12][CH2:13][CH3:14])=[O:11].[F:15][C:16]1[CH:17]=[C:18]([CH:21]=[CH:22][C:23]=1[F:24])[CH2:19]Br.Cl>CN(C=O)C>[F:15][C:16]1[CH:17]=[C:18]([CH:21]=[CH:22][C:23]=1[F:24])[CH2:19][N:9]1[C:4](=[O:3])[C:5]([C:10]([O:12][CH2:13][CH3:14])=[O:11])=[CH:6][N:7]=[CH:8]1
A mixture of sodium hydride (0.262 g, 6.54 mmol, 60% dispersion in mineral oil) and ethyl 6-oxo-1,6-dihydropyrimidine-5-carboxylate (1 g, 5.95 mmol) was dissolved in DMF (11.89 ml). After 30 min at room temperature, 3,4-difluorobenzyl bromide (0.761 ml, 5.95 mmol) was added. The reaction mixture was stirred at room temperature overnight and then poured into aqueous hydrochloric acid (10%). The aqueous layer was extracted with ethyl acetate. The combined organic extracts were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel, eluting with ethyl acetate/hexanes, to afford ethyl 1-(3,4-difluorobenzyl)-6-oxo-1,6-dihydropyrimidine-5-carboxylate as an off-white solid. LRMS (EST) calc'd for (C14H13F2N2O3) [M+H]+, 295.1; found 295.1.
Wird geladen…
