[N+:1]([C:4]1[CH:11]=[C:10]([O:12][CH3:13])[C:9]([O:14][CH3:15])=[C:8]([O:16][CH3:17])[C:5]=1C=O)([O-:3])=[O:2].ClC1C=CC=C(C(OO)=[O:26])C=1.[OH-].[K+].CO>C(Cl)(Cl)Cl>[OH:26][C:5]1[C:8]([O:16][CH3:17])=[C:9]([O:14][CH3:15])[C:10]([O:12][CH3:13])=[CH:11][C:4]=1[N+:1]([O-:3])=[O:2]A mixture of 2-nitro-4,5,6-trimethoxybenzaldehyde (19.3 g, 0.08 mol) and m-chloroperbenzoic acid (20.7 g, 0.12 mol) in chloroform (350 ml) was heated under reflux for 5 hours. After cooling, the reaction mixture was washed with 10% sodium bicarbonate solution and water. The solvent was removed by evaporation in vacuo and the residue was then treated with a mixture of 10% potassium hydroxide solution (potassium hydroxide 5.0 g, 0.088 mol in 50 ml of water) and methanol (150 ml) at room temperature under nitrogen. The solvent was removed in vacuo and the solid residue was dissolved in water (300 ml) and then acidified with 6N hydrochloric acid. The precipitated product was collected by filtration, washed well with water and dried to give (after recrystallization from 2-propanol) 13.1 g of 2-hydroxy-1-nitro-3,4,5-trimethoxybenzene, mp 72-73° C. 1H-NMR (CDCl3): δ3.87, 3.94, and 4.08 (each 3H, s, 3 ×OMe), 7.32 (1H, s, H-6), 10.78 (1H, exchangeable, OH). Analyses: Calculated for C9H11NO6 : C, 47.16; H, 4.84; N, 6.11. Found: C, 47.11; H, 5.00; N, 6.17.
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