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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1777774Generated: November 1, 2026

1,1'-Carbonyldiimidazole → 8-bromo-[1,2,4]triazolo[4,3-a]pyridin-3(2H)-one

https://huagongshe.com/reaction/1777774

Reaction equation

Participants

RoleNameHCIDCharge
Reactant1,1'-CarbonyldiimidazoleHCID 68263—
Reactant3-Bromo-2-hydrazinopyridineHCID 50999406—
SolventWaterHCID 962—
SolventTetrahydrofuranHCID 8028—
SolventEthyl AcetateHCID 8857—
Product8-bromo-[1,2,4]triazolo[4,3-a]pyridin-3(2H)-oneHCID 6718766235.1%

Reaction Steps

To a solution of 1-4 (5.0 g, 26.6 mmol) in THF (50 mL) was added carbonyldiimidazole (5.61 g, 34.6 mmol), and the heterogeneous mixture was stirred for 2 h. The reaction was diluted with water (150 mL) and EtOAc (150 mL), causing a precipitate to form. The mixture was filtered through a sintered glass filter, yielding 2.0 g (35%) of 1-5 as a tan solid. 1H NMR (300 MHz, DMSO-d6) δ12.73 (s, 1H), 7.88 (dd, J=7.2, 0.9 Hz, 1H), 7.58 (dd, J=7.2, 0.9 Hz, 1H), 6.51 (app t, J=7.2 Hz, 1H).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09266881B2
Source datasetuspto-grants-2016_02
ORD IDord-d31fbade04944a5ca91765771b39c816
Source noteuspto-grants-2016_02