[CH3:1][O:2][C:3](=[O:11])[C:4]1[CH:9]=[CH:8][CH:7]=[N:6][C:5]=1[NH2:10].C(N(CC)CC)C.[Cl:19][C:20]1[CH:21]=[C:22]([CH:26]=[CH:27][N:28]=1)[C:23](Cl)=[O:24]>ClCCl>[CH3:1][O:2][C:3](=[O:11])[C:4]1[CH:9]=[CH:8][CH:7]=[N:6][C:5]=1[NH:10][C:23]([C:22]1[CH:26]=[CH:27][N:28]=[C:20]([Cl:19])[CH:21]=1)=[O:24]A stirred and chilled (0° C.) mixture of 2-amino-nicotinic acid methyl ester (11 g, 72.3 mmol) in dichloromethane was treated sequentially with triethylamine (11 mL, 79.5 mmol) and a solution of 2-chloro-isonicotinoyl chloride (12.73 g, 72.3 mmol) in dichloromethane, such that the total volume of solvent was 80 mL. The reaction was warmed to room temperature and on completion of the reaction was quenched by addition of water. The aqueous phase was separated and extracted with EtOAc. The combined organic phases were washed with brine, dried and concentrated in vacuo. The residue was suspended in hot hexane, filtered while hot and the resulting solid recrystallised from EtOH, to give 2-[(2-chloro-pyridine-4-carbonyl)-amino]-nicotinic acid methyl ester (12.76 g); 1H-NMR (300 MHz, d6-DMSO) 11.47 (1H, s), 8.62-8.67 (2H, m), 8.20 (1H, unresolved dd), 7.99 (1H, s), 7.89 (1H, unresolved dd), 7.43 (1H, dd), 3.72 (3H, s).
Wird geladen…
