反应详情

温度

20 °C

The 2-amino-3:5-dinitrothiophene was itself obtained by reacting the sodium salt of cyanoacetic acid with the dimer of mercaptoacetaldehyde in aqueous medium at 80° C, cooling to 20° C, adding acetic anhydride while maintaining the pH at 6-7, acidifying and isolating the 2-acetylaminothiophene-3-carboxylic acid. This was then dinitrated in sulphuric acid medium at 0° C, the resulting 2-acetylamino-3:5-dinitrothiophene being isolated and then deacetylated by heating in an aqueous solution of sulphuric acid. Table I gives further Examples of the dyestuffs of the invention of the formula ##STR16## the symbols of which have the values given in the respective columns of the Table, while the last column of the Table gives the shades obtained when the dyestuffs are applied to an aromatic polyester textile material.

1. customobtained
2. customat 80° C
3. temperaturewhile maintaining the pH at 6-7