C([O:8][C:9](=[O:25])[CH:10]([C:12]1[CH:17]=[CH:16][C:15]([N:18]2[CH:22]=[C:21]([Cl:23])[CH:20]=[N:19]2)=[C:14]([Cl:24])[CH:13]=1)[CH3:11])C1C=CC=CC=1.[H][H]>C(OCC)(=O)C.C(O)(=O)C.[Pd]>[Cl:24][C:14]1[CH:13]=[C:12]([CH:10]([CH3:11])[C:9]([OH:25])=[O:8])[CH:17]=[CH:16][C:15]=1[N:18]1[CH:22]=[C:21]([Cl:23])[CH:20]=[N:19]1375 mg (1 mmole) of 2-[3-chloro-4-(4-chloropyrazol-1-yl)phenyl]propionic acid benzyl ester are hydrogenolyzed in the presence of 50 mg of 10% palladium/activated charcoal at room temperature and at atmospheric pressure in a mixture of 100 ml of ethyl acetate and 10 ml of glacial acetic acid in a rotary hydrogenation apparatus until the theoretical amount of hydrogen has been absorbed. Filtration from the catalyst is effected, the filtrate is concentrated in a vacuum, and the residue is dissolved in a 1 N solution of sodium hydroxide. The resulting aqueous solution is extracted with benzene; acidification is effected with 1 N hydrochloric acid, followed by extraction again with benzene. The organic phase is dried and concentrated to yield 230 mg (80.7% of theory) of 2-[3-chloro-4-(4-chloropyrazol-1-yl)phenyl]propionic acid (m.p. 102° to 103° C.).
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