1-(3-Bromo-2-fluorophenyl)-N,5-dimethoxy-N-methyl-4-oxo-1,4-dihydropyridazine-3-carboxamide → 3-Acetyl-1-(3-bromo-2-fluorophenyl)-5-methoxypyridazin-4(1H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-(3-bromo-2-fluorophenyl)-N,5-dimethoxy-N-methyl-4-oxo-1,4-dihydropyridazine-3-carboxamide (4.22 g, 10.9 mmol) in THF (218 mL) was added MeMgBr (1.0 M in THF, 16.4 mL, 16.4 mmol) at −78° C. under N2. The mixture was stirred at −78° C. for 2 h. The reaction was quenched with saturated NH4Cl aqueous solution at −78° C. The mixture was diluted with NaHCO3 aqueous solution, extracted with EtOAc, dried over Na2SO4, filtered, concentrated in vacuo and purified by column chromatography on silica gel (EtOAc/MeOH=100/0 to 50/50) to yield the title compound (3.48 g, 93% yield) as a yellow solid: 1H-NMR (DMSO-d6, 300 MHz): δ ppm 2.50 (3H, s), 3.80 (3H, s), 7.36-7.46 (1H, m), 7.77-7.85 (1H, m), 7.89-7.99 (1H, m), 8.57 (1H, d, J=1.9 Hz).

Provenance & Evidence