Cl.[CH2:2]([O:9][C:10]1[CH:15]=[CH:14][C:13]([N+:16]([O-])=O)=[C:12]([CH3:19])[CH:11]=1)[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.C(=O)([O-])[O-].[K+].[K+]>C(O)C.[Zn]>[CH2:2]([O:9][C:10]1[CH:15]=[CH:14][C:13]([NH2:16])=[C:12]([CH3:19])[CH:11]=1)[C:3]1[CH:4]=[CH:5][CH:6]=[CH:7][CH:8]=1A solution of 190 ml of concentrated hydrochloric acid in 300 ml of ethanol is added dropwise to a mixture of 50 g of 4-benzyloxy-2-methyl-1-nitrobenzene and of 46 g of zinc. The solution is cooled to around 45° C. by means of an ice bath throughout the running-in process. The medium is stirred for 3 hours at ambient temperature. The pH of the solution is adjusted to around pH 8 by adding 500 ml of a saturated potassium carbonate solution. The precipitate is filtered off and washed with 5×500 ml of ethyl acetate. The organic phases are combined and washed with 2×1 liter of distilled water, then with 1 liter of a saturated sodium chloride solution. After drying over magnesium sulfate, the solvent is evaporated off under reduced pressure in a rotary evaporator. The reaction crude is purified by flash chromatography (silica 35-70 μm), eluent: ethyl acetate/cyclohexane 80:20; 75:25; 70:30. 30.81 g of 4-benzyloxy-2-methylphenylamine are isolated.
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