Triethylamine → 1-(3-Diethylaminopropyl)-3-[4-(2-fluoro-4-nitrophenoxy)pyridin-2-yl]urea

Participants

Reaction Steps

To a solution of 4-(2-fluoro-4-nitrophenoxy)pyridin-2-ylamine (400 mg, 1.61 mmol) and triethylamine (0.455 ml, 3.26 mmol) in tetrahydrofuran (40 ml) was added phenyl chloroformate (0.307 ml, 2.45 mmol) dropwise while stirring in an ice bath, followed by stirring for 0.5 hr. The reaction mixture was concentrated under a reduced pressure to give a residue, to which N,N-dimethylformamide (20 ml) and N,N-diethyl-1,3-propanediamine (606 mg, 4.2 mmol) were then added, followed by stirring at room temperature for 1 hr and 45 min. To the reaction mixture was added ethyl acetate (150 ml), washed with a saturated aqueous solution of sodium hydrogencarbonate, and dried over anhydrous sodium sulfate. The solvent was evaporated to give a residue, which was then purified by silica gel column chromatography (Fuji Silysia NH, eluent; hexane:ethyl acetate=1:2, then ethyl acetate) to provide the titled compound (653 mg, 83.8%) as a pale yellow oil.

Provenance & Evidence