[CH2:1]([O:3][C:4]1[C:5]([O:17][CH3:18])=[CH:6][C:7]([N+:14]([O-])=O)=[C:8]([CH:13]=1)[C:9]([O:11][CH3:12])=[O:10])[CH3:2].[Cl-].[NH4+]>O.CO.[Fe]>[NH2:14][C:7]1[CH:6]=[C:5]([O:17][CH3:18])[C:4]([O:3][CH2:1][CH3:2])=[CH:13][C:8]=1[C:9]([O:11][CH3:12])=[O:10]A mixture of 17.0 g (66.7 mmol) of methyl 5-ethoxy-4-methoxy-2-nitrobenzoate, 13.1 g (233 mmol) of powdered iron and 17.7 g (334 mmol) of ammonium chloride in 95 mL of water and 245 mL of methanol was refluxed for 4.5 h. An additional 13.1 g of iron was added followed by refluxing for 2.5 h. Then an additional 13.1 g of iron and 17.7 g of ammonium chloride was added and refluxing was continued for 12 h. The reaction was filtered through Celite and methanol was removed from the filtrate. The filtrate was extracted with chloroform and the extracts were treated with Darco, evaporated and dried in vacuo (50° C.). The yield was 11.0 g of methyl 2-amino-5-ethoxy-4-methoxybenzoate as tan crystals: mass spectrum (electrospray, m/e): M+H 225.9.
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