[OH:1][C:2]1[N:9]=[CH:8][C:7]([C:10]([F:13])([F:12])[F:11])=[CH:6][C:3]=1[CH:4]=O.C([O-])=O.[Na+].Cl.[NH2:19]O>C(O)=O>[OH:1][C:2]1[N:9]=[CH:8][C:7]([C:10]([F:13])([F:12])[F:11])=[CH:6][C:3]=1[C:4]#[N:19]A mixture of 2-hydroxy-5-(trifluoromethyl)nicotinaldehyde (3.80 g, 17.9 mmol) (approx. 90% purity), sodium formate (1.46 g, 20.8 mmol), hydroxylamine hydrochloride (1.47 g, 20.8 mmol) in formic acid (36.6 mL) was stirred at room temperature for 2 h (cloudy brown solution) and then heated to reflux overnight (first clear brown solution, then cloudy again). After being cooled to room temperature, the reaction mixture was quenched with water and extracted with EtOAc three times. The combined organic layers were washed with water, dried over MgSO4, filtered, and concentrated in vacuo to yield 3.03 grams (90%) of the desired crude product (approx. 75% purity) as a brown solid. MS calculated for C7H3F3N2O: (M+H)+189; found 189.0.
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