[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([OH:12])=[C:6]([CH:11]=1)[C:7]([O:9][CH3:10])=[O:8].Cl[C:14]1[CH:19]=[CH:18][C:17]([N+:20]([O-:22])=[O:21])=[CH:16][N:15]=1.C(=O)([O-])[O-].[K+].[K+].O>CN(C)C=O>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([O:12][C:14]2[CH:19]=[CH:18][C:17]([N+:20]([O-:22])=[O:21])=[CH:16][N:15]=2)=[C:6]([CH:11]=1)[C:7]([O:9][CH3:10])=[O:8]A mixture of methyl 5-chloro-2-hydroxybenzoate (2.35 g, 12.6 mmol), 2-chloro-5-nitropyridine (2.00 g, 12.6 mmol), and potassium carbonate (5.23 g, 37.8 mmol) in N,N-dimethylformamide (50 mL) was stirred at 120° C. for 1 h. The reaction mixture was poured into water and the aqueous mixture was extracted with a mixture (3/1) of ethyl acetate and toluene. The organic extracts were washed with brine, dried over sodium sulfate, and concentrated. The residue was purified by flush column chromatography on silica gel eluting with hexane/ethyl acetate (4/1) to afford 3.79 g (97%) of the title compound: 1H-NMR (CDCl3) δ 8.94 (1H, d, J=2.8 Hz), 8.52 (1H, dd, J=9.0, 2.8 Hz), 8.05 (1H, d, J=2.8 Hz), 7.60 (1H, dd, J=8.6, 2.8 Hz), 7.18 (1H, d, J=8.6 Hz), 7.14 (1H, d, J=9.0 Hz), 3.73 (3H, s).
Wird geladen…