反应详情

温度

100 °C

To a suspension of 4-amino-2-fluoro-benzoic acid (1 g, 6.38 mmol) in sulfuric acid 75% (15 mL) were added glycerol anhydrous (2.108 mL, 28.72 mmol) and sodium 3-nitrosulfonate (2.93 g, 12.8 mmol). The mixture was stirred at 100° C. for 4 h. It was then cooled down to 60° C. and EtOH was added. The mixture was then stirred at 60° C. for 45 h. The solution was poured into ice-water mixture and then basified with saturated aqueous ammonium hydroxide. It was extracted twice with EtOAc. The organic phases were joined and washed with brine, dried over Na2SO4 and concentrated. The residue was purified by MPLC eluting with a DCM/MeOH gradient to afford a yellow oil as a mixture (1:1) of 5-fluoro-quinoline-6-carboxylic acid ethyl ester and 7-fluoro-quinoline-6-carboxylic acid ethyl ester (tR 1.3 min and tR 1.1 min (conditions 6), MH+=220).

1. temperatureIt was then cooled down to 60° C.
2. stirringThe mixture was then stirred at 60° C. for 45 h
3. extractionIt was extracted twice with EtOAc
4. washwashed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated
7. customThe residue was purified by MPLC
8. washeluting with a DCM/MeOH gradient