反应详情

Bromine (100 g.) was dropwise added over 40 minutes under reflux to a solution of ethyl 2-methoxyiminoacetoacetate (a mixture of syn and anti isomers) (100 g.) in a mixture of carbon tetrachloride (300 ml.) and acetic acid (300 ml.). The mixture was stirred at 70° to 80° C. until the evolution of hydrogen bromide ceased. The reaction mixture was washed twice with water (300 ml.), a sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution and dried over magnesium sulfate. The solution was treated with activated charcoal (2 g.) and concentrated under reduced pressure to give ethyl 2-methoxyimino-4-bromoacetoacetate (a mixture of syn and anti isomers) (120.8 g.).

1. additiona mixture of syn and anti isomers) (100 g.)
2. washThe reaction mixture was washed twice with water (300 ml.)
3. dry with materiala sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution and dried over magnesium sulfate
4. additionThe solution was treated with activated charcoal (2 g.)
5. concentrationconcentrated under reduced pressure