[CH3:1][O:2][C:3]1[C:4]([N+:11]([O-:13])=[O:12])=[C:5]([CH:8]=[CH:9][CH:10]=1)[CH:6]=O.[OH-].[Na+].Cl.[N+:17]([CH3:20])([O-:19])=[O:18]>O.CO>[CH3:1][O:2][C:3]1[C:4]([N+:11]([O-:13])=[O:12])=[C:5]([CH:8]=[CH:9][CH:10]=1)[CH:6]=[CH:20][N+:17]([O-:19])=[O:18]Compound 2 was prepared according to the procedure of A. Kalir et al. [Isr. J. Chem. 5: 129-136 (1967)]. To a 100-mL round bottom flask, 6.674 g of powdered 3-methoxy-2-nitrobenzaldehyde (98%, Aldrich) (36.87 mmol), 2.1 mL of nitromethane (39 mmol), and 15.5 mL of methanol were added. This suspension was cooled to approximately 5° C., and 5.6 mL of 9.5N aqueous sodium hydroxide (53 mmol) was added. An additional 1 mL of nitromethane, 9.5N aqueous sodium hydroxide, and methanol was added. The reaction mixture was stirred for 1 hr at approximately 5° C. Over the course of the hour an additional 5 mL of methanol was added. After 1 hr the precipitate was dissolved in 25 mL of water. This solution was added to 20 mL of 10% aqueous hydrochloric acid. The resulting precipitate was extracted with three 100-mL portions, one 50-mL portion, and finally one 25-mL portion of diethyl ether. The ether extracts were combined, dried with MgSO4, and filtered. The ether was removed by rotary evaporation and the residue was refluxed for 5 min in 31 mL of acetic anhydride and 3.566 g of anhydrous sodium acetate. The solution was allowed to cool and then was diluted with water. The precipitate was collected. Recrystallization from hot methanol with a recovery of a second crop of crystals from the mother liquor yielded 5.891 g (71%) of 2 as yellow crystals: 1H NMR (CDCl3) δ 3.94 (s, 3H, OCH3), 7.19 (d, 2H, J=8.3 Hz), 7.50 (m, 2H), 7.85 (d, 1H, J=13.7 Hz).
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