[F:1][CH:2]([F:20])[O:3][C:4]1[CH:9]=[CH:8][C:7]([C:10]2[CH:11]=[N:12][CH:13]=[C:14]([CH:19]=2)[C:15]([O:17][CH3:18])=[O:16])=[CH:6][CH:5]=1>C(O)(=O)C.[Pd].[Pt](=O)=O>[F:20][CH:2]([F:1])[O:3][C:4]1[CH:5]=[CH:6][C:7]([CH:10]2[CH2:11][NH:12][CH2:13][CH:14]([C:15]([O:17][CH3:18])=[O:16])[CH2:19]2)=[CH:8][CH:9]=1A solution of 8.6 g (30.9 mmol) of methyl 5-[4-(difluoromethoxy)phenyl]nicotinate in concentrated acetic acid (112 ml) was admixed with 841 mg of palladium/carbon (10% palladium) and 1.12 g of platinum(IV) oxide. This was followed by hydrogenation under a hydrogen atmosphere at standard pressure for 24 h. The reaction solution was concentrated under reduced pressure. The residue was taken up in water, acidified (pH 1) with 1 N hydrochloric acid, extracted with diethyl ether, then basified (pH>10) with saturated aqueous sodium hydrogencarbonate solution and extracted repeatedly with ethyl acetate. The combined filtrates were dried over sodium sulphate, filtered and concentrated under reduced pressure. Yield: 6.6 g (74% of theory)
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