反应详情

To a solution of 4.0 g (17 mol) of methyl 2-benzyloxyiminoacetoacetate in 50 ml of methanol, 1.56 g (18.7 mmol) of methoxyamine hydrochloride was added and the mixture was heated under reflux for 3 hours. After distilling the solvent off under reduced pressure, 50 ml of water was added and the mixture was extracted twice with 50 ml of diethylether and then washed with water and a saturated aqueous sodium chloride. The organic layer was dried over with anhydrous magnesium sulfate and the solvent was distilled off to obtain a residue, which was then purified by a column chromatography on a silica gel (n-hexane/ethyl acetate) to obtain 4.11 g (yield:91%) of methyl 2-benzyloxyimino-3-methoxyiminobutyrate as a colorless oil. 1H-NMR(CDCl3) δ ppm:1.99(3H, s), 3.86(3H, s), 3.94(3H, s), 5.21(2H, s), 7.33(5H, m).

1. temperaturethe mixture was heated
2. temperatureunder reflux for 3 hours
3. distillationAfter distilling the solvent off under reduced pressure, 50 ml of water
4. additionwas added
5. extractionthe mixture was extracted twice with 50 ml of diethylether
6. washwashed with water
7. dry with materialThe organic layer was dried over with anhydrous magnesium sulfate
8. distillationthe solvent was distilled off
9. customto obtain a residue, which
10. customwas then purified by a column chromatography on a silica gel (n-hexane/ethyl acetate)