2,3-Diamino-5-methylpyridine

Synthesis

The general procedure for the synthesis of 2,3-diamino-5-methylpyridine from 2-amino-3-nitro-5-methylpyridine was as follows: the Pd/C catalyst (50 mg, 0.47 mmol) was added to a stirring solution of 2-amino-5-methyl-3-nitropyridine (500 mg, 3.27 mmol) in methanol (7 mL). Subsequently, the reaction system was evacuated three times and charged with hydrogen displacement. The reaction was stirred at 20 °C for 5 h under hydrogen atmosphere. Upon completion of the reaction, the reaction mixture was filtered through diatomaceous earth and the filter cake was washed with additional methanol (30 mL). The filtrate was concentrated under reduced pressure to afford the target product 2,3-diamino-5-methylpyridine (395 mg, 98% yield). The product was characterized by 1H NMR (MeOD): δ 7.22 (dd, J = 2.0, 0.9 Hz, 1H), 6.81 (dd, J = 2.0, 0.7 Hz, 1H), 2.13 (t, J = 0.7 Hz, 3H). Mass spectral analysis showed m/z = 124 (100).

References

[1] Journal of Medicinal Chemistry, 1997, vol. 40, # 22, p. 3679 - 3686
[2] Patent: WO2017/219083, 2017, A1. Location in patent: Page/Page column 73; 74
[3] Patent: US2014/315888, 2014, A1. Location in patent: Paragraph 0754-0755
[4] Journal of the American Chemical Society, 1950, vol. 72, p. 2806
[5] Patent: US5620978, 1997, A