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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 587499Generated: October 30, 2026

Phosphorus oxychloride → 2-chloro-1-methyl-1H-imidazo[4,5-b]pyridine

https://huagongshe.com/reaction/587499

Reaction equation

Participants

RoleNameHCIDCharge
ReactantPhosphorus oxychlorideHCID 24813—
Reactant1-Methyl-1h-imidazo[4,5-b]pyridin-2(3h)-oneHCID 854236—
ReactantCalcium ChlorideHCID 5284359—
Product2-chloro-1-methyl-1H-imidazo[4,5-b]pyridineHCID 58577270—

Reaction Steps

The mixture of 1-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (1.1 g) and phosphorus oxychloride (6.87 mL) was stirred at 100° C. under a dry atmosphere (CaCl2 tube) for 5 h. The mixture was neutralized with sat.NaHCO3 at 0° C. and extracted with EtOAc. The organic layer was separated, washed with water and brine, dried over MgSO4 and concentrated in vacuo. The residue was purified by column chromatography (NH silica gel, eluted with 0%-50% EtOAc in hexane) to give 2-chloro-1-methyl-1H-imidazo[4,5-b]pyridine (600 mg) as a white solid.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09226921B2
Source datasetuspto-grants-2016_01
ORD IDord-f0c3cb19144a403a976786e9c0ae8793
Source noteuspto-grants-2016_01