反应详情

To a stirred solution of 2-chloro-5-fluoronicotinic acid (2.0 g, 10 mmol) and tert-butyl 4-(aminomethyl)benzoate (1.65 g, 8 mmol) in dichloromethane (25 mL) were successively added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) (2.88 g, 15 mmol), 1-hydroxybenzotriazole hydrate (HOBT) (1.53 g, 10 mmol), and triethylamine (5 mL). After being stirred overnight, the reaction mixture was poured into water (100 mL). The organic layer_was separated and the aqueous layer was extracted with dichloromethane (50 mL×2). The combined organic layers were washed with brine (100 mL), dried (sodium sulfate), and evaporated. The residue was purified by flush column chromatography on silica gel (200 g) eluting with dichloromethane/ethyl acetate (20/1) to afford 2.39 g (82%) of the title compounds as white solids: 1H-NMR (CDCl3) δ 8.33 (1H, d, J=3.1 Hz), 7.97 (2H, d, J=8.4 Hz), 7.91 (1H, dd, J=7.9, 3.1 Hz), 7.40 (2H, d, J=8.4 Hz), 7.04 (1H, br.s), 4.70 (2H, d, J=5.9 Hz), 1.58 (9H, s).

1. customThe organic layer_was separated
2. extractionthe aqueous layer was extracted with dichloromethane (50 mL×2)
3. washThe combined organic layers were washed with brine (100 mL)
4. dry with materialdried (sodium sulfate)
5. customevaporated
6. customThe residue was purified
7. customby flush column chromatography on silica gel (200 g)
8. washeluting with dichloromethane/ethyl acetate (20/1)