Synthesis
4-Hydroxy-3-nitropyridine (2.8 g, 20.0 mmol) was dissolved in 150 mL of methanol and 280 mg of Pd/C catalyst was added. The air in the reaction flask was replaced with hydrogen, which was continuously vented, and the reaction was carried out at room temperature, and the progress of the reaction was monitored by thin-layer chromatography (TLC) until the completion of the reaction. The reaction mixture was filtrated, the filter cake was washed with methanol, the filtrates were combined and concentrated under reduced pressure to give 3-amino-4-hydroxypyridine as a black to orange oily liquid (1.98 g, 90% yield).
References
[1] Patent: US2007/105891, 2007, A1. Location in patent: Page/Page column 10
[2] Patent: US2011/28467, 2011, A1. Location in patent: Page/Page column 15
[3] Patent: CN108373476, 2018, A. Location in patent: Paragraph 0390-0394
[4] Journal of Medicinal Chemistry, 2015, vol. 58, # 24, p. 9742 - 9753
[5] Roczniki Chemii, 1955, vol. 29, p. 119,127
