反应详情

2-Amino-4-(4-nitrophenoxy)pyridine (761 mg) was dissolved in tetrahydrofuran (14 ml) under a nitrogen atmosphere, and then triethylamine (1.16 ml) and phenyl chloroformate (1.05 ml) were added dropwise while cooling in an ice water bath, followed by stirring for 30 min. To the reaction mixture was added 2 N dimethylamine (a solution in methanol) (6.95 ml), followed by stirring overnight. The reaction mixture was partitioned between ethyl acetate and a saturated aqueous solution of ammonium chloride. The organic layer was washed with a saturated aqueous solution of ammonium chloride, a saturated aqueous solution of sodium hydrogencarbonate, water and brine in this order, and dried over anhydrous sodium sulfate. The solvent was evaporated under a reduced pressure to give a residue, which was then purified by silica gel column chromatography (eluent; hexane:ethyl acetate=1:1 to 1:5). Fractions containing the target compound were concentrated under a reduced pressure to give a residue, which was then dried in vacuum to provide the titled compound (609 mg, 72.5%) as a brown solid.

1. temperaturewhile cooling in an ice water bath
2. stirringby stirring overnight
3. customThe reaction mixture was partitioned between ethyl acetate
4. washThe organic layer was washed with a saturated aqueous solution of ammonium chloride
5. dry with materiala saturated aqueous solution of sodium hydrogencarbonate, water and brine in this order, and dried over anhydrous sodium sulfate
6. customThe solvent was evaporated under a reduced pressure
7. customto give a residue, which
8. customwas then purified by silica gel column chromatography (eluent; hexane:ethyl acetate=1:1 to 1:5)
9. additionFractions containing the target compound
10. concentrationwere concentrated under a reduced pressure
11. customto give a residue, which
12. customwas then dried in vacuum