反应详情

129 g. of sodium 5-chloro-2-sulfothiophene-3-carboxylate are dissolved hot in a solution of 84.7 g. of caustic potash in 430 ml. of water, acidified with 130 ml. of concentrated HCl to a pH of 1, and slowly cooled to 5°. The precipitate that separates out is suction filtered without rewashing. The filtrate is concentrated by evaporation to 220 ml. and again cooled to 5°. The precipitate that separates out is suction filtered, combined with the previously obtained product, and dried in vacuo at 110°. Potassium 5-chloro-2-sulfothiophene-3-carboxylate is obtained.

1. filtrationThe precipitate that separates out is suction filtered without rewashing
2. concentrationThe filtrate is concentrated by evaporation to 220 ml
3. temperatureand again cooled to 5°
4. filtrationThe precipitate that separates out is suction filtered
5. customdried in vacuo at 110°