反应详情

3.0 g (10 mmoles) of 2-[3-chloro-4-(4-chloropyrazol-1-yl)phenyl]propionic acid methyl ester, 1.4 g of potassium hydroxide, 1.5 ml of water and 20 ml of ethanol are heated to the boil for 2 hours, the alcohol is distilled off, water is added and extraction with benzene is effected. This is followed by clarification of the aqueous phase with activated charcoal and acification with 2 N hydrochloric acid to produce 2.7 g (95% of theory) of 2-[3-chloro-4-(4-chloropyrazol-1-yl)-phenyl]propionic acid (m.p. 102° to 103° C.).

1. distillationthe alcohol is distilled off
2. additionwater is added
3. extractionextraction with benzene