C(=O)(O)[O-:2].[Na+].Cl.NO.[C:9]([C:11]1[CH:16]=[C:15]([C:17]([F:20])([F:19])[F:18])[CH:14]=[CH:13][N:12]=1)#[N:10]>C(O)C>[F:19][C:17]([F:20])([F:18])[C:15]1[CH:14]=[CH:13][N:12]=[C:11]([C:9]([NH2:10])=[O:2])[CH:16]=1To 72 ml of ethanol were added 6.18 g of sodium bicarbonate and 5.11 g of hydroxylamine hydrochloride, and the mixture was heated to reflux for 45 minutes. After allowing to cool, 6 g of 2-cyano-4-trifluoromethylpyridine was added at 0° C., and the mixture was stirred, and concentrated. To the residue was added water, the resultant solution was extracted with ethyl acetate three times, and the organic layers were combined, washed with an aqueous saturated sodium chloride solution, dried with anhydrous magnesium sulfate, and concentrated. The residue was subjected to silica gel column chromatography to obtain 5 g of 4-trifluoromethylpyridine-2-carboxamide=oxime.
Wird geladen…