1-(2-Fluoro-4-iodophenyl)-N,5-dimethoxy-N-methyl-4-oxo-1,4-dihydropyridazine-3-carboxamide → 3-Acetyl-1-(2-fluoro-4-iodophenyl)-5-methoxypyridazin-4(1H)-one
Reaction equation
[CH3:1][Mg+].[Br-].[F:4][C:5]1[CH:10]=[C:9]([I:11])[CH:8]=[CH:7][C:6]=1[N:12]1[CH:17]=[C:16]([O:18][CH3:19])[C:15](=[O:20])[C:14]([C:21](N(OC)C)=[O:22])=[N:13]1>C1COCC1>[C:21]([C:14]1[C:15](=[O:20])[C:16]([O:18][CH3:19])=[CH:17][N:12]([C:6]2[CH:7]=[CH:8][C:9]([I:11])=[CH:10][C:5]=2[F:4])[N:13]=1)(=[O:22])[CH3:1]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
MeMgBr (1 M solution in THF, 70 mL, 70 mmol) was added dropwise at −78° C. to a solution of 1-(2-fluoro-4-iodophenyl)-N,5-dimethoxy-N-methyl-4-oxo-1,4-dihydropyridazine-3-carboxamide (9.96 g, 23 mmol) in THF (250 mL). After stirring for 1 h, the reaction mixture was quenched with 1 M HCl aqueous solution and extracted with AcOEt. The extract was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography eluting with AcOEt and recrystallized from MeOH to give the title compound (2.05 g, 23% yield) as pale yellow crystals: mp 196-198° C.; 1H NMR (300 MHz, CDCl3): δ ppm 2.67 (3H, s), 3.90 (3H, s), 7.36-7.41 (1H, m), 7.66-7.71 (2H, m), 7.73 (1H, d, J=2.6 Hz). Anal. Calcd for C13H10FIN2O3: C, 40.23; H, 2.60; N, 7.22. Found: C, 40.25; H, 2.87; N, 7.28.