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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1772109Generated: October 25, 2026

1-Ethyl-1h-pyrazol-4-amine → 5-Bromo-3-(1-ethyl-1H-pyrazol-4-ylamino)-1-methylpyrazin-2(1H)-one

https://huagongshe.com/reaction/1772109

Reaction equation

Participants

RoleNameHCIDCharge
Reactant1-Ethyl-1h-pyrazol-4-amineHCID 7018640—
Reactant3,5-Dibromo-1-methyl-1H-pyrazin-2-oneHCID 13062969—
Product5-Bromo-3-(1-ethyl-1H-pyrazol-4-ylamino)-1-methylpyrazin-2(1H)-oneHCID 5804374175.3%

Reaction Steps

Using the same general procedure as Example 102k, reaction of 111b (500 mg, 4.50 mmol) and 3,5-dibromo-1-methylpyrazin-2(1H)-one (1.33 g, 4.95 mmol) afforded a 75% yield (1.01 g) of 111c as an off-white solid: mp 237-239° C.; 1H NMR (300 MHz, DMSO-d6) δ 9.90 (s, 1H), 8.02 (s, 1H), 7.73 (s, 1H), 7.20 (s, 1H), 4.11 (q, 2H, J=7.5 Hz), 3.41 (s, 3H), 1.34 (t, 3H, J=7.3 Hz); MS (ESI+) m/z 298.0 (M+H).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09249123B2
Source datasetuspto-grants-2016_02
ORD IDord-ed0064cd18264ffc9535711f00e92677
Source noteuspto-grants-2016_02