[N+:1]([C:4]1[CH:5]=[C:6]([CH:19]=[CH:20][C:21]=1[N+:22]([O-])=O)[CH2:7][N:8]1[C:16](=[O:17])[C:15]2[C:10](=[CH:11][CH:12]=[CH:13][CH:14]=2)[C:9]1=[O:18])([O-])=O.C(O)C.C1COCC1>[Pd].C(O)(=O)C>[NH2:1][C:4]1[CH:5]=[C:6]([CH:19]=[CH:20][C:21]=1[NH2:22])[CH2:7][N:8]1[C:16](=[O:17])[C:15]2[C:10](=[CH:11][CH:12]=[CH:13][CH:14]=2)[C:9]1=[O:18]A mixture of 2-(3,4-dinitrobenzyl)isoindole-1,3-dione (8 g, 24.4 mmol), prepared as in Example 1, and 10% palladium on carbon (300 mg) was combined with anhydrous ethanol (200 mL, anhydrous THF (100 mL) and glacial acetic acid (30 mL) under a continuous stream of nitrogen. The mixture then was stirred vigorously 15 hours at room temperature under hydrogen, filtered and concentrated to a volume of approximately 30 mL by rotary evaporation. The mixture was diluted with water (100 mL) and ammonium hydroxide was added to give an orange precipitate. The precipitate was isolated by filtration and washed several times with water to provide 2-(3,4-diaminobenzyl)isoindole-1,3-dione (6 g, 91% yield); 1H-NMR (300 Mhz, DMSO-d6): 7.76-7.85 (m, 4H), 6.31-6.43 (m, 3H), 4.51 (broad s, 4H), 4.47 (s, 2H).
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