5-ethyl-1-(2-methoxyethyl)-4-nitro-1H-pyrazole-3-carboxamide → 4-amino-5-ethyl-1-(2-methoxyethyl)-1H-Pyrazole-3-carboxamide

Participants

Reaction Steps

A mixture of 5-ethyl-1-(2-methoxyethyl)-4-nitro-1H-pyrazole-3-carboxamide (20 g, 82.6 mMol) and 5% Pd/C (1 g) in methanol (200 mL) was pressurised at 50psi/25° C. in a sealed vessel and stirred for 15 hours. At the end of the reaction the mixture was filtered through arbocel and the filter cake was washed with methanol. The methanolic solution was distilled at atmospheric pressure and replaced with ethyl acetate to a final volume of 100 mL. The cooled mixture was granulated at ambient temperature for 2 h filtered and washed with ethyl acetate (20 mL) to afford 4-amino-5-ethyl-1-(2-methoxyethyl)-1H-pyrazole-3-carboxamide as a white crystalline solid, 15 g, 88%. m.p.=131° C. Found: C, 50.75; H, 7.62; N, 26.38. C9H16N4O2 requires C, 50.94; H, 7.55; N, 26.42%. δ (CDCl3): 1.20 (3H, t), 2.63 (2H, q), 3.32 (3H, s), 3.74 (2H, t), 3.95 (2H, s), 4.15 (2H, t), 5.27 (1H, s), 6.59 (1H, s).

Provenance & Evidence