Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1492721Generated: October 28, 2026

Ethyl 2-oxocyclopentanecarboxylate → 5-(trifluoromethyl)pyridine-2-sulfonic Acid

https://huagongshe.com/reaction/1492721

Reaction equation

Participants

RoleNameHCIDCharge
ReactantEthyl 2-oxocyclopentanecarboxylateHCID 69136—
Reactant1-Fluoro-5-(trifluoromethyl)pyridin-1-ium-2-sulfonateHCID 2737618—
Solvent1,2-DichloroethaneHCID 11—
Product5-(trifluoromethyl)pyridine-2-sulfonic AcidHCID 1075176295.5%

Reaction Steps

A mixture of ethyl 2-oxocyclopentanecarboxylate (148 μl, 1 mmol), N-fluoro-5-(trifluoromethyl)pyridinium-2-sulfonate (245 mg, 1 mmol) and 1,2-dichloroethane (2 ml) was heated under reflux in an argon atmosphere for 6 hours. Thereafter, the precipitate was recovered by filtration and washed with methylene chloride to obtain 5-trifluoromethylpyridine-2-sulfonic acid (217 mg). Yield, 96%. Analysis of the filtrate by 19F-NMR revealed that ethyl 1-fluoro-2-oxocyclopentanecarboxylate was produced at a yield of 57%.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05374732
Source datasetuspto-grants-1994_12
ORD IDord-84d855ebfcc449b7ace72cf355e93d11
Source noteuspto-grants-1994_12