Phosphorus oxychloride → HCID 57970207, compound

Participants

Reaction Conditions

Reaction Steps

4-(Trifluoromethoxy)aniline (10 mL) was added dropwise to ethyl acetoacetate (44 mL) at 160° C., and the mixture was stirred at the same temperature for 1 h. The mixture was left stand for cooling to room temperature and crystallized with hexane to obtain 3-oxo-N-(4-(trifluoromethoxy)phenyl)butane amide (6.5 g). (2) To concentrated sulfuric acid (32.5 mL) was added 3-oxo-N-(4-(trifluoromethoxy)phenyl)butane amide (6.5 g), and the mixture was stirred at 95° C. for 3 h. The reaction solution was added dropwise to water with ice cooling, and the precipitated crystals were collected by filtration. The resulting crystals were suspended in water, the suspension was made basic with aqueous ammonia, and the precipitated crystals were collected by filtration to obtain 4-methyl-6-(trifluoromethoxy)quinoline-2(1H)-one (1.87 g). (3) A mixture of 4-methyl-6-(trifluoromethoxy)quinoline-2(1H)-one (1.87 g) and phosphorus oxychloride (19 mL) was stirred at 105° C. for 2.5 h. The reaction solution was added dropwise to water with ice cooling, and the precipitated crystals were collected by filtration to obtain 2-chloro-4-methyl-6-trifluoromethoxyquinoline (1.98 g).

Provenance & Evidence