Ethyl 3-(3,4-difluorophenyl)-3-oxopropanoate → 7-(3,4-Difluorophenyl)-2-methylpyrazolo[1,5-a]pyrimidin-5(4H)-one
Reaction equation
[CH3:1][C:2]1[CH:6]=[C:5]([NH2:7])[NH:4][N:3]=1.[F:8][C:9]1[CH:10]=[C:11]([C:16](=O)[CH2:17][C:18](OCC)=[O:19])[CH:12]=[CH:13][C:14]=1[F:15]>N1C=CC=CC=1>[F:8][C:9]1[CH:10]=[C:11]([C:16]2[N:4]3[N:3]=[C:2]([CH3:1])[CH:6]=[C:5]3[NH:7][C:18](=[O:19])[CH:17]=2)[CH:12]=[CH:13][C:14]=1[F:15]Participants
4
Procedure
3-Methylpyrazol-5-amine (670 mg) and ethyl 3-(3,4-difluorophenyl)-3-oxopropanoate (1.12 g) are stirred overnight in a pyridine (30 mL) solvent at 85° C. After cooling to room temperature, the reaction solvent is removed by distillation under reduced pressure. The remainder is extracted with ethyl acetate and water. The extracted organic layer is washed with brine and dehydrated with anhydrous MgSO4. The dehydrated organic layer is distilled under reduced pressure and the target compound (821 mg) is yielded by column chromatography. 1H NMR (CDCl3, 300 MHz) δ 10.80 (br, 1H), 8.01 (m, 1H), 7.54 (m, 1H), 7.30 (m, 1H), 6.45 (s, 1H), 5.88 (s, 1H), 2.31 (s, 3H).