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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1696196Generated: October 31, 2026

Hydrochloric Acid → 4-Chloropyridin-2-amine--hydrogen chloride (1/1)

https://huagongshe.com/reaction/1696196

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantTriethylamineHCID 8471—
ReactantP,P-Diphenylphosphinic azideHCID 199401—
Reactant4-Chloropyridine-2-carboxylic acidHCID 230890—
SolventWaterHCID 962—
Solventtert-ButanolHCID 6386—
Solvent1,4-DioxaneHCID 31275—
Product4-Chloropyridin-2-amine--hydrogen chloride (1/1)HCID 53302030—

Reaction Conditions

Temperature100 °C

Reaction Steps

To a solution of 4-chloro-2-pyridinecarboxylic acid (5.95 g) in tert-butanol (89.25 mL) were added triethylamine (6.32 mL) and diphenylphosphoryl azide (8.95 mL). The mixture was stirred at 100° C. for overnight. To the solution was added water and the mixture was extracted with EtOAc and washed with water and brine. The extract was dried over MgSO4 and concentrated under reduced pressure. The residue was recrystallized with EtOAc to give a white solid. The solid was dissolved in dioxane (50 mL). To the solution was added 4M HCl in dioxane (90 mL) and the mixture was stirred at ambient temperature overnight. The mixture was concentrated under reduced pressure to give 4-chloro-2-pyridinamine hydrochloride (3.02 g) as a white solid.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS08163767B2
Source datasetuspto-grants-2012_04
ORD IDord-b30eb359faba4260b8476a08651b3750
Source noteuspto-grants-2012_04