[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[CH2:9][C:10](=[N:12][OH:13])[CH3:11].C([BH3-])#N.[Na+]>C(O)(=O)C>[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[CH2:9][CH:10]([NH:12][OH:13])[CH3:11]A solution of 1-(2,4-dichlorophenyl)-propan-2-one oxime (3.3 g, 15.1 mmol) in acetic acid (30 ml) was treated at 10° C. with sodium cyanoborohydride (1.90 g, 30.3 mmol) added in small portions over 10 minutes and the resulting solution was stirred at 23° C. for 5 hours. The solvent was evaporated under reduced pressure (co-evaporation with toluene twice) and the residue was slurried with water and pH was adjusted to 10 with 1M NaOH. The aqueous phase was extracted with dichloromethane (3×20 ml), washed with brine and dried over anhydrous Na2SO4. After removal of the solvent (100 mbar; 45° C.), 3.18 g (96.0% of theory) of N-[2-(2,4-dichlorophenyl)-1-methyl-ethyl]-hydroxylamine was obtained in form of a white solid (m.p. 83-86° C.).
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