[CH3:1][N:2]1[C:6]([CH3:7])=[C:5]([C:8](=[O:10])C)[CH:4]=[N:3]1.[Br:11]N1C(=O)CCC1=O>C1COCC1.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>[Br:11][CH2:7][C:6]1[N:2]([CH3:1])[N:3]=[CH:4][C:5]=1[CH:8]=[O:10]To a stirred solution of 1-(1,5-dimethyl-1H-pyrazol-4-yl)ethanone (471 mg, 3.42 mmol) in THF (13 ml) was added N-bromosuccinimide (637 mg, 3.58 mmol) and benzoyl peroxide (41 mg, 0.17 mmol) at room temperature under nitrogen, then the resulting mixture was refluxed for 20 h. After cooling, the reaction mixture was evaporated to remove the solvents. The residue was chromatographed on a column of silica gel eluting with ethyl acetate-hexane (1:1) gave the title compound as white solid (574 mg, 78% yield). 1H NMR (270 MHz, CDCl3) 2.47 (3H, s), 3.91 (3H, s), 4.87 (2H, s), 7.83 (1H, s). MS (ESI) m/z: 217 (M+H)+.
Wird geladen…
