反应详情

A stirred solution of methyl 3-butyryl-4-hydroxybenzoate, pyridine (3.7 mL, 46 mmol), and hydroxylamine hydrochloride (3.55 g, 51 mmol) in ethanol (30 mL) was heated reflux for 2 h. The mixture was concentrated under reduced pressure and partitioned between water and ethyl acetate. The organic layer was washed with 1 N hydrochloric acid, saturated sodium bicarbonate, dried (sodium sulfate), filtered, and concentrated under reduced pressure to afford a crude oil. Purification by flash column chromatography (silica, 10:1 hexanes/ethyl acetate) provided methyl 4-hydroxy-3-[(1E)-N-hydroxybutanimidoyl]benzoate (170 mg): 1H NMR (500 MHz, CD3OD): δ 8.30-8.28 (m, 1H), 7.85-7.82 (m, 1H), 6.92-6.89 (m, 1H), 3.88 (s, 3H), 2.87-2.84 (m, 2H), 1.67-1.60 (m, 2H), 1.05-1.00 (m, 3H).

1. temperaturereflux for 2 h
2. concentrationThe mixture was concentrated under reduced pressure
3. custompartitioned between water and ethyl acetate
4. washThe organic layer was washed with 1 N hydrochloric acid, saturated sodium bicarbonate
5. dry with materialdried (sodium sulfate)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customto afford a crude oil
9. customPurification by flash column chromatography (silica, 10:1 hexanes/ethyl acetate)