反应详情

A solution of ethyl 2-chloro-2-(hydroxyimino)acetate (11 g; 70.41 mmol) in ethyl acetate (60 mL) was added dropwise at room temperature to a mixture of 3-bromoprop-1-yne (15.2 mL; 141 mmol), sodium bicarbonate (11.95 g; 141 mmol), ethyl acetate (400 mL), and water (4 mL). The mixture was stirred at room temperature for 24 h and the solid was removed by filtration and washed with ethyl acetate. The filtrate was concentrated under reduced pressure and the residue was purified by flash chromatography on silica gel (eluent: 15 to 100% of dichloromethane in heptane) to give 14.38 g (87%) of ethyl 5-(bromomethyl)isoxazole-3-carboxylate as a white solid.

1. customthe solid was removed by filtration
2. washwashed with ethyl acetate
3. concentrationThe filtrate was concentrated under reduced pressure
4. customthe residue was purified by flash chromatography on silica gel (eluent: 15 to 100% of dichloromethane in heptane)