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

HRID 1492721Notes

Reaction equation

HRID 1492721 reaction equation
O=C1CCCC1C(OCC)=O.F[N+:13]1[CH:18]=[C:17]([C:19]([F:22])([F:21])[F:20])[CH:16]=[CH:15][C:14]=1[S:23]([O-:26])(=[O:25])=[O:24]>ClCCCl>[F:22][C:19]([F:20])([F:21])[C:17]1[CH:16]=[CH:15][C:14]([S:23]([OH:26])(=[O:25])=[O:24])=[N:13][CH:18]=1

Participants

4

Reactant 2

HCID 69136Ethyl 2-oxocyclopentanecarboxylateHCID 27376181-Fluoro-5-(trifluoromethyl)pyridin-1-ium-2-sulfonate

Product 1

HCID 107517625-(trifluoromethyl)pyridine-2-sulfonic AcidYield 95.5%

Reagents, catalysts & solvents 1

HCID 111,2-DichloroethaneSolvent

Procedure

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%.

Workup

  1. temperaturewas heated
  2. temperatureunder reflux in an argon atmosphere for 6 hours
  3. filtrationThereafter, the precipitate was recovered by filtration
  4. washwashed with methylene chloride

Sources & evidence

ORD record
ord-84d855ebfcc449b7ace72cf355e93d11
Source dataset
uspto-grants-1994_12
Patent number
US05374732

Reaction notes

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