Synthesis
General procedure for the synthesis of 2-nitro-5-hydroxybenzoic acid from 5-chloro-2-nitrobenzoic acid: 5-chloro-2-nitrobenzoic acid (32.00 g, 0.159 mol) was dissolved in 15% aqueous sodium hydroxide solution and reacted at reflux under nitrogen protection for 72 hours. After completion of the reaction, the pH of the reaction solution was adjusted to 1.0 with dilute hydrochloric acid and then extracted with ethyl acetate. The ethyl acetate extracts were combined and dried with anhydrous sodium sulfate. The solvent was removed by distillation under reduced pressure to give 28.05 g of 2-nitro-5-hydroxybenzoic acid in 96.5% yield.
References
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