Ammonium Chloride → 7-chloro-5-fluoro-4-methyl-1H-indole

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Reaction Conditions

Reaction Steps

Under an atmosphere of argon, 4-chloro-2-fluoro-5-nitrotoluene (1.9 g) was dissolved with anhydrous tetrahydrofuran (100 mL), and the reaction mixture was stirred at −50° C. Vinylmagnesium bromide (1.0 M solution in tetrahydrofuran, 40 mL) was dropped to the reaction mixture. The reaction mixture was raised slowly to −20° C. for 40 minutes. A saturated aqueous solution of ammonium chloride was added to the reaction mixture, and the reaction mixture was extracted with ethyl acetate. The obtained organic layer was washed with water and a saturated salt solution. The obtained extract was concentrated under reduced pressure after drying with sodium sulfate. The obtained residue was purified by column chromatography on silica gel (hexane:ethyl acetate=95:5→91:9) to give the title compound (1.09 g) having the following physical data.

Provenance & Evidence