反应详情

To a mixture of 5-hydroxyanthranilic acid (50 g, 0.33 mol), sodium hydrogen carbonate (109 g, 1.3 mol) and water (200 ml) was added dropwise a solution of benzyl chloroformate (52 ml, 0.36 mol) in diethyl ether (200 ml) with stirring, and the mixture was stirred at room temperature for 3 hrs. The reaction mixture was acidified by adding conc. hydrochloric acid and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated and the obtained crystals were washed with diisopropyl ether and hexane to give 2-{[(benzyloxy)carbonyl]amino}-5-hydroxybenzoic acid (91.6 g, yield 98%) as brown crystals.

1. stirringthe mixture was stirred at room temperature for 3 hrs
2. extractionthe mixture was extracted with ethyl acetate
3. washThe extract was washed with saturated brine
4. dry with materialdried over anhydrous magnesium sulfate
5. customThe solvent was evaporated
6. washthe obtained crystals were washed with diisopropyl ether and hexane