6-chloro-N-(3-methoxypropyl)-3-nitropyridin-2-amine → 6-chloro-N2-(3-methoxypropyl)pyridine-2,3-diamine

6-Chloro-N-(3-methoxypropyl)-3-nitropyridin-2-amine (2.84 mmol, 0.698 g) was added to an oven dried 50 mL round-bottomed flask equipped for stirring under nitrogen. Methanol (15 mL) and acetic acid (1.5 mL, glacial) were then added. Zinc (15.29 mmol, 1.0 g, 20-30 mesh) was then added and the resultant mixture was allowed to stir at room temperature for 16 hr. Analysis of the reaction by LC/MS indicated a complete conversion to product at this time. This resultant mixture was then filtered over Celite®, concentrated in-vacuo, and transferred to a 250 mL seperatory funnel with ethyl acetate (2×30 mL) and water (2×20 mL). The layers were separated and the organic layer was washed once with saturated aqueous sodium chloride (40 mL). The organic layer was collected and subsequently dried with anhydrous Na2SO4 and filtered. This filtrate was collected, concentrated, and dried in-vacuo affording 6-chloro-N2-(3-methoxypropyl)pyridine-2,3-diamine (35A) as a brown oil which was used directly in the next step without further purification. ESI-MS: mix 216.3 (M+H)+.