[C:1](#[N:4])CC.Cl[C:6]1[C:11]([Cl:12])=[CH:10][C:9]([C:13]([F:16])([F:15])[F:14])=[CH:8][N:7]=1.[C-]#N.[Na+]>CN(C)C1C=CN=CC=1.O>[Cl:12][C:11]1[C:6]([C:1]#[N:4])=[N:7][CH:8]=[C:9]([C:13]([F:16])([F:15])[F:14])[CH:10]=1Propionitrile (656 ml), 2,3-dichloro-5-trifluoromethylpyridine (87.5 g) and 4-dimethylaminopyridine (52 g) were heated at reflux for 5 hours under nitrogen. The mixture was cooled and a solution of sodium cyanide (30 g) in water (110 ml) added at 15° C. After stirring at 15° C. for 5 hours the reaction was complete and water (250 ml) added to dissolve the inorganic salts. The organic phase was washed with water followed by extraction with 2N HCl to remove 4-dimethylaminopyridine. Propionitrile was removed by vacuum distillation at 40° C. to give the product, 3-chloro-2-cyano-5-trifluoromethylpyridine in 73 to 84% yield.
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