反应详情

To a solution of 2-(3,4-bis{[2-(methyloxy)ethyl]oxy}phenyl)-3-oxobutanenitrile (0.57 g, 1.9 mmol) in ethanol (5 mL) was added hydrazine dihydrochloride (0.20 g, 2.2 mmol) The resulting mixture was heated at reflux for 1 hour. It was cooled, pour into a saturated sodium bicarbonate solution (10 mL), and the mixture was extracted with ethyl acetate (3×10 mL). The combined extract was washed with aqueous sodium bicarbonate solution, brine, dried over sodium sulfate, filtered and concentrated to give an oily residue which was purified by flash chromatography (silica gel, 5% methanol-dichloromethane) to provide 4-(3,4-bis{[2-(methyloxy)ethyl]oxy}phenyl)-3-methyl-1H-pyrazol-5-amine (0.46 g, 1.4 mmol, 74% yield). 1H NMR (400 MHz, CDCl3): 6.96-6.92 (m, 2H), 6.87-6.84 (d, d, 1H), 4.19-4.16 (m, 4H), 3.79-3.76 (m, 4H), 3.67 (s, 2H), 3.46 (s, 3H), 3.44 (s, 3H), 2.25 (s, 3H).

1. temperaturewas heated
2. temperatureat reflux for 1 hour
3. temperatureIt was cooled
4. extractionthe mixture was extracted with ethyl acetate (3×10 mL)
5. extractionThe combined extract
6. washwas washed with aqueous sodium bicarbonate solution, brine
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customto give an oily residue which
11. customwas purified by flash chromatography (silica gel, 5% methanol-dichloromethane)