反应详情

14 g of manganese dioxide was added to a solution having 5.4 g of (2,3,4-trimethoxy-6-methylphenyl)(2,6-dichloro-4-trifluoromethyl-3-pyridyl)methanol obtained in step (a) dissolved in 140 ml of toluene, followed by stirring under reflux by heating for 6 hours. The mixture was cooled and then subjected to filtration, and toluene was distilled off under reduced pressure to obtain 4.4 g (yield 81%) of 3-(2,3,4-trimethoxy-6-methylbenzoyl)-2,6-dichloro-4-trifluoromethylpyridine (compound No. 3; m.p. 81-83° C.).

1. temperatureunder reflux
2. temperatureby heating for 6 hours
3. temperatureThe mixture was cooled
4. filtrationsubjected to filtration, and toluene
5. distillationwas distilled off under reduced pressure