[Br:1][C:2]1[C:3]([F:16])=[C:4](NC(=O)OC(C)(C)C)[CH:5]=[CH:6][CH:7]=1.[CH:17](=O)/[CH:18]=[CH:19]/[CH3:20].[OH-].[NH4+:23]>Cl.O1CCOCC1>[Br:1][C:2]1[C:3]([F:16])=[C:4]2[C:5]([CH:17]=[CH:18][C:19]([CH3:20])=[N:23]2)=[CH:6][CH:7]=1A solution of tert-butyl 3-bromo-2-fluorophenylcarbamate (6.0 g, 20.7 mmol) in 4N HCl (30 mL) in dioxane was stirred at ambient temperature for 2 hours. The solvent was removed under reduced pressure. The residue was dissolved in 6 N HCl (100 mL) and (E)-but-2-enal (2.96 ml, 36.2 mmol) was added dropwise at 106° C. The reaction was stirred at 106° C. for 2 hours. After cooling to ambient temperature, the reaction mixture was basified with ammonium hydroxide to about pH 12, extracted with DCM (2×100 mL), dried (sodium sulfate), filtered and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel (5:1 hexane/ethyl acetate) to give 7-bromo-8-fluoro-2-methylquinoline (2.99 g, 60.2%) as a solid.
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