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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 2738Generated: October 25, 2026

Phosphorus oxychloride → 2-Chloroisonicotinic acid

https://huagongshe.com/reaction/2738

Reaction equation

Participants

RoleNameHCIDCharge
ReactantPhosphorus oxychlorideHCID 24813—
Reactant4-Pyridinecarboxylic acid, 1-oxideHCID 26130—
Product2-Chloroisonicotinic acidHCID 236985—

Reaction Conditions

Temperature120 °C

Reaction Steps

Phosphorus oxychloride (220.7 g) was added to isonicotinic acid N-oxide (50.064 g), and the mixture was stirred on an oil bath at 120° C. for 7 hours. The reaction mixture was slowly poured into ice water with vigorously stirring to precipitate light yellow crystals. The mixture was adjusted to approximately pH 4 with 4N NaOH aqueous solution. The resulting crystals were filtered out, washed with water, and dried by vacuum heating (60° C.) to obtain the above-captioned compound ([9]-(92)-467) (37.845 g).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05731310
Source datasetuspto-grants-1998_03
ORD IDord-8debf37587f1426b9a2fd8782e5c9316
Source noteuspto-grants-1998_03