[CH3:1][O:2][C:3]([C:5]1[CH:14]=[C:13]2[C:8]([CH:9]=[CH:10][C:11]([C:15]([F:18])([F:17])[F:16])=[N:12]2)=[C:7]([OH:19])[CH:6]=1)=[O:4].[N+:20]([O-])([OH:22])=[O:21].CCCCCC>C(OCC)(=O)C>[CH3:1][O:2][C:3]([C:5]1[CH:14]=[C:13]2[C:8]([CH:9]=[CH:10][C:11]([C:15]([F:18])([F:16])[F:17])=[N:12]2)=[C:7]([OH:19])[C:6]=1[N+:20]([O-:22])=[O:21])=[O:4]5-Hydroxy-2-trifluoromethyl-quinoline-7-carboxylic acid methyl ester (46.0 g, 169.63 mmol) is dissolved in 200 ml of concentrated (97%) sulphuric acid at 0-5° C. To this cooled solution is added drop wise fuming (100%) nitric acid (7 ml, 10.69 g, 169.63 mmol). After the addition is complete, the reaction mixture is allowed to warm to room temperature. TLC analysis (4:1 hexane:ethyl acetate) after 30 min shows reaction completion. The reaction mixture is slowly poured onto an ice/water mixture (ca. 2 l), and the crystals then filtered at the pump, thoroughly washed with water, and dried in vacuo. This affords the title compound (47.0 g, 87.6%) as pale yellow crystals.
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