Ethyl Acetate → 2-Amino-4-(2-fluoro-4-nitrophenoxy)pyridine

Participants

Reaction Conditions

Reaction Steps

2-Amino-4-chloropyridine (8.00 g) was dissolved in N-methylpyrrolidone (65 ml), and then 2-fluoro-4-nitrophenol (19.55 g) and N,N-diisopropylethylamine (43.36 ml) were added thereto, followed by stirring at 160° C. for 41 hrs. The reaction mixture was cooled down to room temperature, and partitioned between ethyl acetate-tetrahydrofuran (1:1) and a 2 N aqueous solution of sodium hydroxide. The organic layer was washed with water and brine in this order. The aqueous layer was extracted again with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulfate. The solvent was evaporated under a reduced pressure to give a residue, which was purified by silica gel column chromatography (eluent; hexane:ethyl acetate=1:2, then ethyl acetate). Fractions containing the target compound were concentrated to provide a residue, to which ethyl acetate was added to precipitate crystals. The crystals were filtered, and dried under aeration to provide the titled compound (3.02 g, 20%) as opaline crystals.

Provenance & Evidence