反应详情

To a solution of 3-(N-Hydroxycarbamimidoyl)-benzoic acid methyl ester (60 g, 310 mmol) in anhydrous THF (200 mL) was added diisopropylethylamine (75 mL, 434 mmol) at 5° C., and then to the mixture was added 2-fluorobenzoyl chloride (48.1 mL, 403 mmol) over 20 min. The reaction mixture was stirred for 1 h at room temperature. The precipitate was filtered off and the filtrate was concentrated under reduced pressure. The residue was dissolved in ethylacetate (400 mL) and then washed with water (200 mL×2). The solvent was removed under reduced pressure and the desired product was crystallized in 60% ethylacetate in hexane to yield the desired product (81 g, 83% yield) as a white solid. 1H-NMR (CDCl3) δ 8.18 (1H), 8.03 (2H), 7.48 (2H), 7.18 (2H), 5.61 (2H), 3.82 (3H).

1. filtrationThe precipitate was filtered off
2. concentrationthe filtrate was concentrated under reduced pressure
3. dissolutionThe residue was dissolved in ethylacetate (400 mL)
4. washwashed with water (200 mL×2)
5. customThe solvent was removed under reduced pressure
6. customthe desired product was crystallized in 60% ethylacetate in hexane