The general procedure for the synthesis of 5-amino-2-methoxypyridine from 5-nitro-2-methoxypyridine was as follows: 67.28 g of 2-methoxy-5-nitropyridine (0.1 mol), 0.50 g of 10% Pd/C were sequentially added to methanol, hydrogen was passed to a pressure of 0.01 MPa, and the reaction was carried out for 62±1.5 hours. Upon completion of the reaction, the reaction solution was cooled to room temperature and filtered to recover the 10% Pd/C catalyst. The filtrate was concentrated under reduced pressure to recover solvent. The residue was extracted twice with 75 g of dichloroethane and the combined extracts were washed once with purified water. Subsequently, the extract was evaporated under reduced pressure to afford a slightly yellow oily liquid 5-amino-2-methoxypyridine 11.69 g. The purity was determined by HPLC to be 97.63% and the yield was 92.03%.
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