Hydrochloric Acid → 5-Bromo-6-fluoro-2-methylquinoline

Beteiligte Stoffe

Reaktionsschritte

A solution of 20.13 g (0.125 mole) of 6-fluoro-2-methylquinoline in 25 ml of 1,2-dichloroethane was added slowly to a mixture of 25.3 g (0.189 mole) of aluminum chloride and 25 ml of 1,2-dichloroethane. The resulting solution was heated to 70° C.-80° C., and 19.98 g (0.125 mole) of bromine was added dropwise thereto. The reaction mixture was heated at 80° C.-85° C. for about 16 hours and was poured onto ice and acidified by adding 100 ml concentrated hydrochloric acid. 17.04 g (0.125 mole) of zinc chloride was added, and the resulting suspension was heated on a steam bath for 15 minutes. After cooling in an ice bath, the complex was collected by filtration and washed sequentially with 100 ml of cold 3N hydrochloric acid and 100 ml of methylene chloride. The complex was slurried in 100 ml of water, and the pH was adjusted to pH 11 with ammonium hydroxide. The product was collected by filtration, washed with water and dissolved in 150 ml of toluene. The toluene solution was treated with magnesium sulfate and decolorizing charcoal, and was then evaporated to give 22.5 g (0.094 mole) of 5-bromo-6-fluoro-2-methylquinoline, a known compound. The structural assignment was confirmed by nuclear magnetic resonance spectral analysis.

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