[CH3:1][O:2][N:3]=[C:4]([CH3:15])[CH2:5][C:6]1[C:11]([Cl:12])=[CH:10][C:9]([Cl:13])=[CH:8][C:7]=1[Cl:14].C([BH3-])#N.[Na+]>C(O)(=O)C>[CH3:1][O:2][NH:3][CH:4]([CH3:15])[CH2:5][C:6]1[C:7]([Cl:14])=[CH:8][C:9]([Cl:13])=[CH:10][C:11]=1[Cl:12]To a stirred solution of crude 1-(2,4,6-trichloro-phenyl)-propan-2-one O-methyl-oxime prepared as described in example P4, (12.3 g, 0.046 mol) in acetic acid (120 ml), sodium cyanoborohydride (6.1 g, 0.097 mol) was added portionwise at 12 to 15° C. The reaction mass was stirred at ambient temperature for 18 hours. TLC confirmed the completion of reaction, then solvent was evaporated under reduced pressure (co-evaporation with toluene twice). The resulting residue was poured on to 1 N sodium hydroxide solution (150 ml) and extracted with dichloromethane (2×100 ml). The combined organic layer was washed with water (2×100 ml) followed by drying over anhydrous sodium sulfate before evaporating the solvent to afford crude O-Methyl-N-[1-methyl-2-(2,4,6-trichloro-phenyl)-ethyl]-hydroxylamine (12.3 g, 100%).
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