Ethanol → 3-Anilino-1-(p-sulfophenyl)-5-pyrazolone

Beteiligte Stoffe

Reaktionsschritte

Into 1.5 l of ethanol were dispersed 118 g of ethylβ-anilino-β-ethoxy acrylate and 94 g of p-sulfophenylhydrazine, and 150 g of triethylamine and glacial acetic acid were successively dropped thereinto while heating (95°-100° C.) and stirring. After heating (95°-100° C.) and stirring for 5 hours, the reaction solution was concentrated under reduced pressure. To the residue so concentrated were added 50 ml of water and 120 ml of ethanol containing 35% by wt. hydrogen chloride to provide a uniform solution. This uniform solution was allowed to stand in a refrigerator for one day and one night. The crystals of the objective compound which precipitated had a melting point of 290° to 291° C. and weighed 145 g.

Herkunft & Nachweise