[Br:1][C:2]1[CH:3]=[C:4]([N+:29]([O-])=O)[C:5]([CH:8](C(OCC2C=CC=CC=2)=O)[C:9](OCC2C=CC=CC=2)=[O:10])=[N:6][CH:7]=1>C(O)(=O)C.[Fe]>[Br:1][C:2]1[CH:3]=[C:4]2[NH:29][C:9](=[O:10])[CH2:8][C:5]2=[N:6][CH:7]=1Iron dust (0.82 g, 14.60 mmol) was added to a solution of dibenzyl 2-(5-bromo-3-nitropyridin-2-yl)malonate (preparation 30b, 1.78 g, 3.70 mmol) in glacial acetic acid (50 mL) and the mixture was heated with stirring to 120° C. After 7 hours, the mixture was cooled and left to stand overnight. The reaction was poured onto ice-water and extracted first with ethyl acetate and then with chloroform. The combined organic extract was washed with brine, dried (MgSO4) and evaporated in vacuo. Purification of the residue by flash chromatography (98:2 dichloromethane/methanol) gave the title compound (0.42 g, 54%) as a pink solid.
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