[NH2:1][C:2]1[C:10]([N+:11]([O-])=O)=[CH:9][C:8]([F:14])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5]>CO.[Pd]>[NH2:1][C:2]1[C:10]([NH2:11])=[CH:9][C:8]([F:14])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5]A pressure flask capable of withstanding 150 psi. was added 2-amino-5-fluoro-3-nitrobenzoic acid (1.2 g, 6.0 mmol) dissolved in methanol (40 mL) and 10% palladium on carbon (150 mg). The reaction was placed in a Parr apparatus and the flask flushed three times with hydrogen leaving an internal pressure of 65 psi. The reaction was continued for 17 hours while maintaining a pressure of 65 psi. The reaction was filtered through celite, washed with methanol and the filtrate evaporated to dryness to give 2,3-diamino-5-fluorobenzoic acid (808 mg, 79%) as a dark brown solid.: m.p. 181°-191° (dec); 1H NMR (400 MHz, DMSO-d6 δ 6.43 (dd, 1H), 6.71 (dd, 1H); 13C NMR (100 MHz, DMSO-d6) δ 102.4, 102.7, 104.6, 104.8, 109.3, 109.4, 137.0, 138.5, 138.6, 152.5, 154.8, 170.1.
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