N[C:2]1[CH:7]=[CH:6][C:5]([CH:8]([CH3:12])[C:9]([OH:11])=[O:10])=[CH:4][C:3]=1[F:13].N([O-])=O.[Cl:17][C:18]([Cl:20])=[CH2:19].C(=O)([O-])O.[Na+].[ClH:26]>CCCCCC.O1CCOCC1.C(OCC)(=O)C.CC(C)=O>[F:13][C:3]1[CH:4]=[C:5]([CH:8]([CH3:12])[C:9]([OH:11])=[O:10])[CH:6]=[CH:7][C:2]=1[CH2:19][C:18]([Cl:26])([Cl:20])[Cl:17]
In 10 ml of a 17% aqueous hydrochloric acid solution was dissolved 2.5 g of 2-(4-amino-3-fluorophenyl)propionic acid. To the solution was added dropwise 5 ml of an aqueous solution of 1.04 g of sodiun nitrite at -15° C.--10° C. with stirring, and the reaction was carried out for an hour. To the mixture were added 25 ml of acetone and 3 g of 1,1-dichloroethylene at -10° C.--5° C., followed by 2.5 g of sodium hydrogen carbonate and 0.5 g of cupric chloride dihydrate. The mixture was gradually warmed up to room temperature and stirred at room temperature for 2 hours. Acetone was evaporated off and the residue was extracted with ether. The ether layer was washed with water and dried over anhydrous magnesium sulfate and the solvent was evaporated off. The residue thus obtained was subjected to silica gel column chromatography (eluent: ethyl acetate--dioxane--n-hexane=1:1:4) and recrystallized from n-hexane to obtain 2.3 g of 2-[3-fluoro-4-(2,2,2-trichloroethyl)phenyl]propionic acid, m.p. 92°-94° C.
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