反应详情

Ethyl 2-(2-formylamino-5-chloro-1,3-thiazol-4-yl)-glyoxylate, which can be represented as ethyl 2-(2-formylimino-5-chloro-2,3-dihydro-1,3-thiazol-4-yl)glyoxylate, (1.3 g.) was dissolved in 1N potassium hydroxide aqueous solution (10 ml.) at room temperature with stirring and the solution was stirred for 5 minutes at the same temperature. After the reaction, the reaction mixture was cooled with ice and then adjusted to pH 1 with 10% hydrochloric acid. The precipitates were collected by filtration, washed with water and then dried to give 2-(2-formylamino-5-chloro-1,3-thiazol-4-yl)glyoxylic acid (0.91 g.), which can be represented as 2-(2-formylimino-5-chloro-2,3-dihydro-1,3-thiazol-4-yl)glyoxylic acid, mp. 148° to 152° C. (dec.). The remaining filtrate and washing were combined together and then extracted with ethyl acetate. The extract was washed with water, dried over magnesium sulfate and then the solvent was distilled off to give further the same object compound (0.23 g.).

1. stirringthe solution was stirred for 5 minutes at the same temperature
2. customAfter the reaction
3. temperaturethe reaction mixture was cooled with ice
4. filtrationThe precipitates were collected by filtration
5. washwashed with water
6. customdried