S(S([O-])=O)([O-])=O.[Na+].[Na+].[Cl:9][C:10]1[CH:11]=[CH:12][C:13]([NH:16][C:17](=[O:29])[C:18]2[CH:23]=[CH:22][CH:21]=[C:20]([O:24][CH3:25])[C:19]=2[N+:26]([O-])=O)=[N:14][CH:15]=1.O1CCCC1.C(=O)([O-])[O-].[K+].[K+]>O.O1CCOCC1>[Cl:9][C:10]1[CH:11]=[CH:12][C:13]([NH:16][C:17](=[O:29])[C:18]2[CH:23]=[CH:22][CH:21]=[C:20]([O:24][CH3:25])[C:19]=2[NH2:26])=[N:14][CH:15]=1To a solution of sodium hydrosulfite (300 g, 1.7 mol) in water (4 L) was added N-(5-chloropyridin-2-yl)-2-nitro-3-methoxybenzamide (140 g, 0.45 mol). Tetrahydrofuran (2 L) and 1,4-dioxane (2 L) were added and the resulting mixture stirred at ambient temperature. After 16 hours, the solution was made basic by addition of potassium carbonate and the phases separated. The organic phase was concentrated of all volatiles in vacuo to give an off-white solid. The solid was washed with water, filtered, and dried under vacuum to afford 111 g (88% yield) of N-(5-chloropyridin-2-yl)-2-amino-3-methoxybenzamide; NMR (CDCl3) 8.8 (br, 1), 8.3 (d, 1), 8.1 (s, 1), 7.7 (dd, 1), 7.1 (dd, 1), 6.8 (d, 1), 6.6 (t, 1), 5.9 (br, 1), 3.9 (s, 3) ppm.
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