p-Toluenesulfonic acid monohydrate → 3-{4-Chloro-2-fluoro-5-[(propoxycarbonyl)methoxy]phenyl}-1-methyl-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine

Participants

Reaction Steps

To a solution of 100 mg of 3-{4-chloro-2-fluoro-5-[(methoxycarbonyl)methoxy]phenyl}-1-methyl-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine (present compound 1-165) in 1.0 ml of propanol was added 10 mg of p-toluenesulfonic acid monohydrate, and the mixture was heated under reflux for 5 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and the excess propanol was distilled out under reduced pressure. The residue was subjected to silica gel column chromatography, which afforded 76 mg (yield, 71%) of 3-{4-chloro-2-fluoro-5-[(propoxycarbonyl)methoxy]phenyl}-1-methyl-6-trifluoromethyl-2-oxo -1,2-dihydropyrazine (present compound 1-167).

Provenance & Evidence