O.Cl.[Cl:3][C:4]1[CH:14]=[C:13]([N+:15]([O-])=O)[CH:12]=[CH:11][C:5]=1[C:6]([N:8]([CH3:10])[CH3:9])=[O:7]>C(O)C.[Fe]>[NH2:15][C:13]1[CH:12]=[CH:11][C:5]([C:6]([N:8]([CH3:10])[CH3:9])=[O:7])=[C:4]([Cl:3])[CH:14]=1Iron powder (pre-reduced with hydrogen, 10.0 g) was suspended in ethanol (80ml) and water (10ml) and concentrated hydrochloric acid (4ml) were added with vigorous stirring. 2-Chloro-4-nitro-N,N-dimethylbenzamide (7.50 g) was added in small portions over 15 minutes and the mixture then heated to 50°-60° C. and stirred for 5 hours. The mixture was filtered through Celite and the ethanol evaporated. Water (200 ml) and concentrated hydrochloric acid (20 ml) were added and the reaction washed with ethyl acetate and then basified to pH8 with sodium bicarbonate and extracted with methylene chloride. The organic extract was dried and evaporated to give 4-amino-2-chloro-N,N-dimethylbenzamide as a grey crystalline solid (5.21 g) which was recrystallised from chloroform/ethyl acetate to give off-white crystals (3.46 g, m.p. 170° 173° C.).
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