65753-52-8

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2-Fluoro-3-(trifluoromethyl)pyridine is a useful synthetic intermediate. It is used to prepare antihypertensive β-?adrenergic blocking agents. It is also used to synthesize HCV NS5B thumb pocket 2 allosteric inhibitors.

General procedure for the synthesis of 2-chloro-3-trifluoromethylpyridine from 2-chloro-3-trifluoromethylpyridine: In a desiccator, anhydrous tetramethylammonium fluoride (NMe4F, 18.6 mg, 0.2 mmol, 2 eq.) and 2-chloro-3-trifluoromethylpyridine (0.1 mmol, 1 eq.) were accurately weighed in a 4 mL sample vial, in which a micro stirring bar was placed in advance. Subsequently, N,N-dimethylformamide (DMF, 0.5 mL) was added as solvent. The sample bottle was removed from the desiccator and the reaction was stirred at room temperature for 24 hours unless otherwise stated. Upon completion of the reaction, the reaction mixture was cooled to room temperature and the internal standard (1,3,5-trifluorobenzene, 100 μL of 0.5 M toluene solution) was added. An appropriate amount of the reaction mixture was taken and analyzed by fluorine-19 nuclear magnetic resonance (59F NMR) spectroscopy and gas chromatography-mass spectrometry (GCMS).

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