O.O.[Sn](Cl)Cl.[CH3:6][O:7][C:8]1[C:13]([N+:14]([O-])=O)=[CH:12][C:11]([C:17]2([CH3:20])[CH2:19][CH2:18]2)=[CH:10][C:9]=1[N+:21]([O-])=O.[OH-].[Na+]>C(OCC)(=O)C>[CH3:6][O:7][C:8]1[C:13]([NH2:14])=[CH:12][C:11]([C:17]2([CH3:20])[CH2:19][CH2:18]2)=[CH:10][C:9]=1[NH2:21]Tin(II)chloride dihydrate (11.9 g, 52.6 mmol) was added to a solution of 2-methoxy-5-(1-methyl-cyclopropyl)-1,3-dinitro-benzene (2.21 g, 8.76 mmol) in ethyl acetate (30 mL). The mixture was heated to reflux for 0.25 h upon which the solution became red in color. The solution was cooled to rt and poured onto aqueous 2.0 M NaOH. The aqueous phase was extracted with ethyl acetate and the combined organic layers were washed with saturated NaHCO3. The organic layers were dried over sodium sulfate, eluted through a plug of silica gel (1% ammonium hydroxide in methylene chloride), and the filtrate was concentrated. The residue was redissolved in Et2O and extracted (3×) with 1.0 M HCl. The pH of the combined aqueous layers was adjusted to pH=12 with 2.0M NaOH and extracted with methylene chloride. The combined organic layers were dried over sodium sulfate, filtered and concentrated to provide 2-methoxy-5-(1-methyl-cyclopropyl)-benzene-1,3-diamine (860 mg, 52%) as a red oil. ESI MS (m/z 193, M+H).
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