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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1165761Generated: November 2, 2026

Phosphorus oxychloride → 2-Chloroisonicotinic acid

https://huagongshe.com/reaction/1165761

Reaction equation

Participants

RoleNameHCIDCharge
ReactantPhosphorus oxychlorideHCID 24813—
ReactantPhosphorus pentachlorideHCID 24819—
Reactant4-Pyridinecarboxylic acid, 1-oxideHCID 26130—
SolventWaterHCID 962—
Product2-Chloroisonicotinic acidHCID 23698566%

Reaction Steps

87 g of isonicotinic acid N-oxide, 350 ml of phosphorus oxychloride and 192 g of phosphorus pentachloride were mixed and refluxed for 3 hours. The reaction mixture was poured into water and left to stand overnight. The resulting precipitate was collected by filtration, and recrystallized from ethanol to give 65 g (66%) of 2-chloro-4-pyridinecarboxylic acid.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04912101
Source datasetuspto-grants-1990_03
ORD IDord-ca3b9aa1af6d4305bb22317ad29399a7
Source noteuspto-grants-1990_03