反应详情

To a solution of 3.2 g of 2-(2-chloroacetamido-4-thiazolyl)-(Z)-2-(n-propoxyimino)acetic acid methyl ester in 50 ml of ethanol is added under ice-cooling and stirring a solution of 2.23 g of potassium hydroxide (85%) in 20 ml of water, and the mixture is stirred for 5 hours at room temperature, followed by concentration under reduced pressure. The concentrate is dissolved in 30 ml of water, and washed twice with 30 ml each portion of ethyl acetate, followed by addition of activated charcoal. The charcoal is removed by filtration and the filtrate is then adjusted to pH 2 with 1N-HCl, and the resulting crystals are collected by filtration, washed with water, hexane and ether in this order to yield 2-(2-chloroacetamido-4-thiazolyl)-(Z)-2-(n-propoxyimino)acetic acid, m.p. 170°-171° C.(decomp.).

1. temperaturecooling
2. concentrationfollowed by concentration under reduced pressure
3. dissolutionThe concentrate is dissolved in 30 ml of water
4. washwashed twice with 30 ml each portion of ethyl acetate
5. additionfollowed by addition of activated charcoal
6. customThe charcoal is removed by filtration
7. filtrationthe resulting crystals are collected by filtration
8. washwashed with water, hexane and ether in this order