[Cl:1][C:2]1[CH:3]=[C:4]([O:11][CH2:12][C:13]2[C:18]([F:19])=[CH:17][CH:16]=[CH:15][C:14]=2[F:20])[C:5]([N+:8]([O-])=O)=[N:6][CH:7]=1.Cl.C([O-])(=O)C.[Na+]>C(O)C.[Fe]>[Cl:1][C:2]1[CH:3]=[C:4]([O:11][CH2:12][C:13]2[C:14]([F:20])=[CH:15][CH:16]=[CH:17][C:18]=2[F:19])[C:5]([NH2:8])=[N:6][CH:7]=159.7 g of 5-chloro-3-[(2,6-difluorobenzyl)oxy]-2-nitropyridine (Example 16A; 199 mmol, 1 equivalent) were initially charged in 600 ml of ethanol, 34.4 g of iron powder (616 mmol, 3.1 equivalents) were added and the mixture was heated to reflux. 152 ml of concentrated hydrochloric acid were slowly added dropwise and the mixture was boiled at reflux for a further 30 min. The reaction mixture was cooled and stirred into an ice/water mixture. The resulting mixture was adjusted to pH 5 using sodium acetate, and the solid was filtered off, washed with water, air-dried and then dried under reduced pressure at 50° C. This gave 52.7 g (98% of theory) of the title compound.
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