Ethanol → 4-Carboxymethyl-1-(2-chloro-phenyl)-5-(4-chloro-phenyl)-1H-pyrazole-3-carboxylic acid

Participants

Reaction Steps

To 1-(2-Chloro-phenyl)-5-(4-chloro-phenyl)-4-cyanomethyl-1H-pyrazole-3-carboxylic acid [B1] (30 g, 0.8 mol) were added sodium hydroxide (19 g, 4.8 mol), ethanol (250 ml) and water (150 ml). The reaction mixture was heated to reflux over night. The heating was removed and the reaction mixture was allowed to reach room temperature. The formed precipitate was collected and washed with ethanol and dried in an exicator over night. The sodium salt was dissolved in water (400 ml) and HCl (4N) was added during extensively stirring, to avoid forming a gum, and the precipitate is collected and dried in a vacuum oven, yielding 27 g (0.7 mol, 86%) of 4-Carboxymethyl-1-(2-chloro-phenyl)-5-(4-chloro-phenyl)-1H-pyrazole-3-carboxylic acid [G1]. LCMS (method A): RT=2.1 min; ES+=390.9 (M+H)+.

Provenance & Evidence