A solution of 6-fluoro-2-methyl-5-{4-[2-(3-nitrophenyl)ethyl]-1-piperazinyl}quinoline (0.05 g; 1 eq) in methanol (3 mL) was added dropwise to a suspension of iron powder (0.05 g; 7 eq) and ammonium chloride (0.05 g; 7 eq) in water (3 mL). The reactants were heated at reflux for 8 hours, with additional amounts of iron powder (total 0.05 g; 7 eq) and ammonium chloride (0.05 g; 7 eq) added in 3 portions during the reaction. The reaction mixture was cooled to room temperature and filtered using a Millipore filter. The filtrate was concentrated under reduced pressure, diluted with water (5 mL) and a saturated aqueous solution of sodium hydrogen carbonate (2 mL) and extracted into ethyl acetate (3×5 mL). The combined organic layers were dried over sodium sulfate and concentrated under reduced pressure to give the title compound in 91% yield (0.04 g).
