1H-1,2,4-Triazole → Ethanone, 1-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-yl)-, oxime

Participants

Reaction Steps

269 g (1 mol) of ω-bromo-2,4-dichloroacetophenone were dissolved in 250 ml of acetonitrile. This solution was added dropwise to a suspension, boiling under reflux, of 69 g (1 mol) of 1,2,4-triazole and 150 g of potassium carbonate in 2 liters of acetonitrile. After heating the mixture under reflux for 20 hours, the cooled suspension was filtered, the filtrate was freed from solvent, the residue was taken up in ethyl acetate and the ethyl acetate solution was washed with water, dried over sodium sulphate and freed from solvent. The residue from the ethyl acetate crystallized out when isopropanol was added. After recrystallizing from ligroin/isopropanol, 154 g (60% of theory) of ω-(1,2,4-triazol-1-yl)-2,4-dichloroacetophenone of melting point 117° C. were obtained. ##STR7## 106.8 g (0.44 mol) of 1-(2,4-dichlorophenyl)-2-(1,2,4-triazol-1-yl)-ethan-1-one were dissolved in 780 ml of ethanol, 48 g of hydroxylammonium hydrochloride were added and the mixture was heated under reflux for 5 hours. Thereafter, 1,000 ml of water were added, and the reaction mixture was filtered. 51 g (45% of theory) of 1-(2,4-dichlorophenyl)-1-oximino-2-(1,2,4-triazol-1-yl)-ethane of melting point 165°-170° C. were obtained. ##STR8##

Provenance & Evidence