反应详情

To a solution of 263 g of diethylamine 2,5-dihydroxy benzene sulfonate in 500 ml of pyridine, 470 g of the chloride of p-chloro phenoxy isobutyric acid are added with stirring. The reaction is exothermic, but it is effected without refrigeration, letting it cool to ambiant temperature. A coloured precipitate forms, which is filtered and washed with water, and then copiously with ethanol. Thus 601 g of the pyridine salt of the di-O-(p-chloro phenoxy isobutyrate) of 2,5-dihydroxy benzene sulfonic acid are obtained in the form of a white crystalline powder having a melting point of 186°-188° C.

1. temperaturecool to ambiant temperature
2. filtrationA coloured precipitate forms, which is filtered
3. washwashed with water