反应详情

A mixture of ethyl 2,4-dioxopentanoate (10.9 g, 68.7 mmol) and N-methoxyamine hydrochloride (4.01 g, 48.1 mmol) in ethanol (40 ml) was left to stand over molecular sieves 3A (25 g) for 18 h and diluted with dichloromethane (25 ml) The sieves was removed by filtration and the filtrate was concentrated under vacuum. The residue was purified by silica gel chromatography eluting with 5% ethyl acetate/n-hexane to give the title compound (12.9 g, 34%).

1. waitwas left
2. customwas removed by filtration
3. concentrationthe filtrate was concentrated under vacuum
4. customThe residue was purified by silica gel chromatography
5. washeluting with 5% ethyl acetate/n-hexane